Coating liquid for forming thin metal oxide film, thin metal oxide film, field-effect transistor and method of making field-effect transistor

FIELD: chemistry.

SUBSTANCE: invention relates to thin metal-oxide films used to make a field-effect transistor. A coating liquid for forming a thin metal oxide film includes an inorganic indium compound, at least one of an inorganic magnesium compound and an inorganic zinc compound, glycolic ether and a diol, wherein the diol is selected from at least one of diethylene glycol, 1,2-propanediol and 1,3-butanediol.

EFFECT: invention enables to obtain a thin-film metal oxide coating with the required resistivity using a simple method, a large area, the required shape and with high accuracy.

12 cl, 10 dwg, 4 tbl

 

Area of technology

The present invention relates to liquid coating for the formation of metal oxide thin film, metal oxide thin film, field effect transistor and a method of producing a field-effect transistor.

The level of technology

Traditionally, the electrodes of the display elements such as liquid crystal display elements and the elements of electroluminescent displays, used metal oxides such as doped antimony tin oxide (ΑΤΟ) and doped with indium tin oxide (ΙΤΟ) as a transparent conductive film. They are also used for teplofizicheskih items to prevent tarnishing or frost the Windows of cars, airplanes and buildings.

In recent years, found that oxide semiconductors such as metal oxides ZnO, In2O3In-Ga-Zn-O, are semiconductors that exhibit a higher mobility of carriers than the carrier mobility of amorphous silicon. Was actively carried out the improvement of field-effect transistors FETs (FET, Field Effect Transistor) using these oxide semiconductors as their active layers.

Basically, the method of forming a thin film of such metal oxides is, for example, a method of vacuum vapor deposition and sputtering method.

However, such methods require �false, costly equipment. In addition, by using these methods it is difficult to form a thin film having a large area.

Thus, in an attempt to create a method by which a thin film having a large area can be formed by a simpler method was proposed liquid coating prepared by dissolving in an organic solvent or a similar inorganic metal compound or organic metal compound and adding to the resulting solution of other metals as an activator to give the film a higher conductivity; and a coating method using the liquid coating.

For example, to form thin film having high conductivity and transmittance, proposed a transparent conductive film-forming composition containing an inorganic compound of indium, magnesium compound and an organic compound capable of coordinating with indium (see PTL 1). Also proposed a transparent conductive film-forming composition containing nitrate India, a condensate of a polyhydric alcohol and an activator dissolved in an organic solvent (see PTL 2).

However, the proposed methods are methods related to the composition to form a transparent Provo�of the present film, and the obtained transparent conductive film cannot satisfactorily function as the active layer of a field effect transistor, and their use is problematic limited.

In addition, proposed a solution of a precursor of a metal oxide containing an inorganic salt of the metal, which serves as a precursor of a metal oxide dissolved in water or ethanol, which are the solvents, and a method of producing an oxide semiconductor by applying to the substrate a solution of precursor of the metal oxide (see PTL 3). Oxide semiconductor obtained by the proposed method was investigated as the active layer of a field effect transistor.

However, if a solution of a precursor of a metal oxide obtained by the proposed method, is applied to the substrate, a solution (liquid coating) thinly spread on the substrate, whereby the accuracy of the contour of the oxide semiconductor obtained is insufficient.

Thus, at present, has increased the demand for the provision of the following: liquid coating for education metallocene thin film (or fluid for the deposition of metal oxide thin film coating), which can form a metal oxide thin film with desired bulk resistivity of prestasi� way to have a large area, and to obtain a metal oxide desired shape with high precision; metal oxide thin film obtained from the liquid for the application of metal-oxide thin-film coatings; field-effect transistor containing an active layer of an oxide semiconductor formed by coating liquid for the application of metal-oxide thin-film coating and method for producing a field-effect transistor.

List of links

PTL 1 Japanese Laid Patent Application (JP-A) No. 06-96619

PTL 2 JP-A No. 07-320541

PTL 3 JP-A No. 2009-177149

A brief summary of the invention

Technical problem

The present invention seeks to solve the problems existing in the prior art and to achieve the following goals. In particular the present invention aims to offer: liquid for coating metal oxide thin film coating, which can form a metal oxide thin film with desired specific volume resistance, the simplest way to have a larger area and to obtain a metal oxide desired shape with high precision; metal oxide thin film obtained from the liquid for the deposition of metal oxide thin film coatings, field-effect transistor containing an active layer of semiconductor oxide is formed by coating gigastudio deposition of metal oxide thin film coating; and a method of producing a field effect transistor.

The solution to the problem

Means to solve the above mentioned problems are as follows.

<1> Liquid coating with the formation of metal oxide thin films, including:

inorganic compound India;

at least one of an inorganic magnesium compounds and inorganic zinc compounds; and

simple glycol ether.

<2> metal Oxide thin film obtained by the method comprising:

the object for coating the coating liquid for coating with the formation of metal oxide thin film according to <1>;

the drying of the object to the coating, which was applied liquid coating;

hot dried drying facility for the coating for the formation of metal oxide thin films on top of it.

<3> Field effect transistor, including:

a gate electrode configured for the application of gate voltage;

the source electrode and the drain electrode, configured to remove the current;

an active layer formed from an oxide semiconductor and disposed between the source electrode and the drain electrode, and

the insulating layer of the gate formed between the gate electrode and the active layer,

this oxide semiconductor about�atovan through the coating liquid for coating with the formation of metal oxide thin film according to < 1>.

<4> a Method of producing a field effect transistor, including:

education on the substrate electrode of the shutter,

the formation of a gate insulating layer on the gate electrode,

the formation of the source electrode and the drain electrode on the insulating layer of the gate so that the source electrode and the drain electrode comprise at intervals from each other to form between them a channel region; and

the formation of the active layer formed of oxide semiconductor on an insulating layer of the gate in the channel region between the source electrode and the drain electrode,

thus the formation of the active layer coating the gate insulating layer liquid coating to form metal oxide thin film according to <1> to thereby form the active layer of the oxide semiconductor.

<5> a Method of producing a field effect transistor, including:

the formation of the source electrode and the drain electrode on the substrate so that the source electrode and the drain electrode comprise at intervals from each other to form between them a channel region;

the formation of the active layer formed of a semiconductor oxide on the substrate in the channel region between the source electrode and the drain electrode;

the formation of a gate insulating layer on the active layer;

the formation of the electrode�the thief on the insulating layer shutter,

thus the formation of the active layer is a coating substrates by a liquid coating with the formation of metal oxide thin film according to <1> to thereby form the active layer of the oxide semiconductor.

The beneficial effects of the invention

The present invention can offer: fluid for the deposition of metal oxide thin-film coating, which can form a metal oxide thin film with desired specific volume resistance, the simplest way to have a large area and have a metal oxide desired shape with high precision; metal oxide thin film obtained from the liquid for the deposition of metal oxide thin film coatings, field-effect transistor containing an active layer of semiconductor oxide is formed by coating liquid for coating metal oxide thin film coating; and a method of producing a field effect transistor. This may solve the existing problem.

Brief description of the drawings

Fig.1 is a schematic structural view of one example of a field effect transistor type bottom gate/bottom contact.

Fig.2 is a schematic structural view of one example of a field effect transistor type, the bottom gate/top contact.

Fig.3 is a schematic struc�kind of one example of a field effect transistor type top gate/bottom contact.

Fig.4 is a schematic structural view of one example of a field effect transistor type top gate/top contact.

Fig.5A is the first stage of one example of a method of producing a field-effect transistor of the present invention.

Fig.5B is the second stage of one example of a method of producing a field-effect transistor of the present invention.

Fig.5C is the third stage of one example of a method of producing a field-effect transistor of the present invention.

Fig.5D is the fourth stage is one example of a method of producing a field-effect transistor of the present invention.

Fig.6 is a schematic view of a condition in which the fluid for the deposition of metal oxide thin-film coating demonstrates good ability to finish.

Fig.7 is a schematic view of a condition in which the fluid for the deposition of metal oxide thin-film coating demonstrates unsatisfactory ability to cover.

Fig.8 is a graph of the relationship between gate voltage Vgs and a current source-drain Ids field-effect transistor obtained in Example 1.

Fig.9 is a graph of the relationship between specific volume resistance and the ratio [B/(A+B)] in each of the fluids coating of Examples 1-27, where And denotes the number of ions In India and represents the amount of grey�the number of magnesium ions and the number of zinc ions.

Fig.10 is a graph of the ratio of viscosity and relationships simple glycol ether diol in a liquid for applying a metal oxide thin film coatings.

Description of embodiments

(The liquid coating for the formation of metal oxide thin films (liquid for the deposition of metal oxide thin-film coating))

The liquid coating for the formation of metal oxide thin film of the present invention comprises at least: an inorganic compound India; at least one inorganic magnesium compounds and inorganic zinc compounds; and a simple glycol ether, and preferably contains a diol. If necessary, the liquid coating further comprises other ingredients.

The use of liquid coating for forming a metal oxide thin film can form a metal oxide thin film having a predetermined volume resistivity.

That is, correcting the state of the liquid coating for the formation of metal oxide thin films, in particular the type of solvent used and the concentration of inorganic compounds (e.g., salts of nitric acid), you can control the specific volume resistance of the formed metal oxide thin film (e.g.�p, thin films of the oxide semiconductor). In addition, specific volume resistance can be controlled by partial substitution of the constituent elements of the oxide, In-Mg and oxide, In-Zn other metal elements.

In addition, it is also possible to control the specific volume resistance through the regulation of the conditions of heat treatment after coating, in particular the calcination temperature, calcination time, the speed of temperature increase, the speed of lowering the temperature of the atmosphere in the calcination (gas fraction and pressure).

In addition, you can use light to accelerate the decomposition of substances, and to continue the reaction. Effective is the optimization of temperature and atmosphere annealing, since the annealing changes the volume resistivity of the formed film.

<Inorganic compound India>

Inorganic compound India is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include oxanilate India, halides India, the hydroxides of indium and cyanide India.

Examples of exocyclic India include nitrate India, sulphate India, carbonate India and phosphate India.

Examples of the halides of indium include chloride India, bromide India and iodide India.

Sredina from the point of view demonstrate a high solubility in various solvents are preferred oxanilate India and the halides of indium, more preferred are nitrate India, sulfate, indium chloride and indium.

Nitrate India is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include hydrates nitrate India. Examples of hydrates nitrate India include nitrate trihydrate India and nitrate pentahydrate India.

Sulfate India is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include anhydrides sulfate India and the hydrates of the sulfate India. Examples of the hydrates of the sulfate India include nonahydrate sulfate India.

Chloride India is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include hydrates of chloride India. Examples of hydrates of chloride India include chloride tetrahydrate India.

These inorganic compounds can be synthesized product or a commercially available product.

<Inorganic magnesium compound and the inorganic compound of zinc>

Inorganic magnesium compound

Inorganic magnesium compound is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include akakiko�s magnesium the halides of magnesium, magnesium hydroxide and magnesium cyanide.

Examples of oxacyclic of magnesium include magnesium nitrate, magnesium sulphates, magnesium carbonates and phosphates of magnesium.

Examples of the halides of magnesium include magnesium chloride, magnesium bromide and magnesium iodide.

Among them, from the point of view demonstrate a high solubility in various solvents are preferred oxanilate magnesium halides and magnesium, more preferred are magnesium nitrate, magnesium sulfate and magnesium chloride.

Magnesium nitrate is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include hydrates of magnesium nitrate. Examples of the hydrate of magnesium nitrate include trihydrate of magnesium nitrate pentahydrate and magnesium nitrate.

Magnesium sulfate is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include the hydrates of magnesium sulfate. Examples of hydrates include magnesium sulfate monohydrate magnesium sulfate and heptahydrate magnesium sulfate.

Magnesium chloride is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include hydrates of magnesium chloride. Examples of hydrates include magnesium chloride hexahydrate chloride� magnesium.

These inorganic compounds can be synthesized product or a commercially available product.

Inorganic compound of zinc

Inorganic compound of zinc is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include oxanilate zinc, zinc halides, zinc hydroxide and zinc cyanide.

Examples of oxacyclic of zinc include zinc nitrate, zinc sulfate, zinc carbonate and zinc phosphate.

Examples of the halides of zinc include zinc chloride, zinc bromide and zinc iodide.

Among them, from the point of view demonstrate a high solubility in various solvents are preferred oxanilate of zinc and halides of zinc, more preferred are zinc nitrate, zinc sulfate and zinc chloride.

Nitrate of zinc is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include hydrates of zinc nitrate. Examples of hydrates of zinc nitrate include trihydrate of zinc nitrate and pentahydrate of zinc nitrate.

Zinc sulfate is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include anhydrides of zinc sulfate and hydrates of zinc sulfate. PR�measures hydrates of zinc sulfate include sulphate dihydrate zinc and heptahydrate of zinc sulfate.

Zinc chloride is not specifically limited and may be appropriately selected depending on the goal. Examples of the above include anhydrides of zinc chloride and the hydrates of zinc chloride. Examples of hydrates of chloride of zinc include zinc chloride dehydrate and zinc chloride Tetra hydrate.

These inorganic zinc compounds can be synthesized product or a commercially available product.

The liquid coating with the formation of metal oxide thin film preferably satisfies the following expression (1):

0,25≤[B/(A+B)]≤0,65 Expression (1)

where And denotes the number of ions of indium in the liquid coating with the formation of metal oxide thin films, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating with the formation of metal oxide thin films.

The liquid coating with the formation of metal oxide thin film which satisfies the above expression (1) can be called also liquid coating to form a thin film of oxide semiconductor.

It is known that a film of indium oxide formed by a sputtering method, has a low resistivity of about 10-4Ω·cm by the addition of tin, zinc, gallium, etc. interested in�quality from about a few percent to about 20 percent. However, a film of indium oxide having a low volume resistivity can't work as an active layer of a field effect transistor.

If the liquid coating with the formation of metal oxide thin film satisfies the above expression (1), a thin film of oxide semiconductor is formed by coating liquid for coating with the formation of metal oxide thin film may be formed so as to have a volume resistivity, a thin film of oxide semiconductor can operate as an active layer of a field effect transistor.

If [B/(A+B)] is less than 0.25, then formed a thin film of oxide semiconductor has a too low volume resistivity. If such a thin film of oxide semiconductor is used as the active layer of a field effect transistor, the active layer is always in a state of conduction regardless of the application of gate voltage, i.e., formed by field-effect transistor can operate as a transistor. Whereas, if [B/(A+B)] exceeds 0,65 formed by a thin film of oxide semiconductor has a too high volume resistivity. If such a thin film of oxide semiconductor is used as the active layer of a field effect transistor, formed�th field-effect transistor has a low emission levels in the state of on/off, ie does not show good characteristics of the transistor.

If a thin film of oxide semiconductor is used as the active layer of a field effect transistor used for excitatory circuits of the display, it requires a thin film of oxide semiconductor, which should have high carrier mobility and so-called normally open characteristics. In order to realize high carrier mobility and normally open characteristics, preferably a volume resistivity of a thin film of oxide semiconductor regulate to get into the range of 10-2Ω·cm to 109Ohm·cm.

When the volume resistivity metal oxide thin film is high, it may be difficult to realize a high mobility of carriers in the Enabled state, controlled by the gate voltage. Thus, the volume resistivity metal oxide thin film is more preferably 106Ω·cm or less.

When the volume resistivity metal oxide thin film is low, it may be difficult to reduce the Ids (current source-drain) OFF state controlled by the gate voltage. Thus, the volume resistivity metal oxide thin film is more preferably 10-1Ω·cm or higher�.

Volume resistivity ρ (Ω·cm) metal oxide thin film expressed by the following equation (2):

ρ = 1/nQµ Equation (2)

where Q(C) denotes the charge carrier, n denotes the density of the media (media/m3) and μ denotes the carrier mobility (m2/volume/s).

Thus, n, Q, and µ can be changed to control the specific volume resistance.

One particular way to control the specific volume resistance of the metal oxide thin film is the way in which the carrier density is changed by controlling the amount of oxygen in the film (density of oxygen defects).

The liquid coating with the formation of metal oxide thin film satisfies the above expression (1) to operate a specific volume resistance, and can form a thin film of oxide semiconductor, effectively used as an active layer of a field effect transistor.

Most effectively, if the liquid coating with the formation of metal oxide thin films are made so as to satisfy the above expression (1), as a method of controlling a volumetric specific resistance of a thin film of oxide semiconductor is formed from it.

<Simple glycol ether>

Simple glycol ether by�completely dissolves the above-mentioned compounds of indium (in particular nitrate India), the above-mentioned magnesium compounds (in particular magnesium nitrate), the aforementioned zinc compounds (in particular, zinc nitrate), and the resulting solution has a high stability. Thus, using a simple glycol ether in the liquid coating with the formation of metal oxide thin film to form a metal oxide thin film (e.g., a thin film of oxide semiconductor) having a high uniformity and fewer defects.

Also, if you use a simple glycol ether in the liquid coating with the formation of metal oxide thin films, it is possible to form a metal oxide thin film (e.g., a thin film of oxide semiconductor) of a predetermined shape with high precision.

I believe that a simple glycol ether serves as a reducing agent. In-Mg oxide semiconductors, and In-Zn oxide semiconductors, which are N-type semiconductors, generate conduction electrons through the formation of oxygen defects. Thus, when shifting the equilibrium towards the restoration of the material may acquire a higher conductivity. The liquid coating with the formation of metal oxide thin film contains a simple glycol ether, and a simple glycol ether exerts its restoring effect in % �CE heat treatment after coating, to thereby obtain a thin film of oxide semiconductor having a lower specific volume resistance.

Simple glycol ether is not specifically limited and may be appropriately selected depending on the goal. Preferred are monoalkyl esters of alkalophiles. The number of carbon atoms contained in the glycol ether is preferably 3-6.

Monoalkylated air alkalophiles is preferably at least one selected among the monoethyl ether of ethylene glycol, monomethyl ether of ethylene glycol, monopropylene ether of ethylene glycol, monoisopropyl ether of ethylene glycol, monobutyl ether of ethylene glycol and monoisobutyl ether of ethylene glycol. These monoalkyl esters of alkalophiles have a boiling point of from about 120°C to about 180°C, and therefore dries quickly. As a result of the liquid coating with the formation of metal oxide thin films becomes difficult to spread. Use this preferred connection can reduce the temperature of calcination to achieve calcination in a relatively short period. In addition, the metal oxide thin film (e.g., a thin film of oxide semiconductor) obtained after calcination, has less impurities� and, therefore, has a high carrier mobility. As a result the graph of the relationship between gate voltage Vgs and a current source-drain Ids field-effect transistor with a thin film of oxide semiconductor as the active layer, the gradient increases observed with the change from DISABLED to ENABLED, becomes large. In other words, it is possible to obtain good switching characteristics, and triggering voltage to obtain the desired current INCLUSION is reduced.

Such monoalkyl esters of alkalophiles can be used individually or in combination.

The number of simple glycol ether in the liquid coating with the formation of metal oxide thin film is not specifically limited and can be selected appropriately depending on the goal. It is preferably from 10 mass% to 80 mass%. If it is less than 10 mass%, the above effects simple glycol ether, in some cases, cannot be obtained. Whereas, if it is greater than 80% by mass, the thickness of the metal oxide thin film (e.g., a thin film of oxide semiconductor), which may be formed by a single coating may be small.

<Diol>

The liquid coating with education�against metal oxide thin film preferably further comprises diol. In other words a simple glycol ether preferably used in combination with diola. If a simple glycol ether and a diol is used in combination, the diol can prevent clogging of inkjet nozzles due to drying of the solvent, if the liquid coating is applied by ink jet method; and a simple glycol ether can prevent the spreading of a liquid coating on unintended areas due to the rapid drying of the liquid coating deposited on a substrate. For example, in the manufacture of a field effect transistor there is the possibility to quickly dry the liquid coating applied to the channel, to prevent the spreading of a liquid coating to other areas except the area of the channel.

Simple glycol ether, typically, has a low viscosity of from about 1.3 CPS to about 3.5 CPS. Thus, if a simple glycol ether appropriately mixed with diola having a high viscosity, the liquid coating with the formation of metal oxide thin films can be easily adjusted in viscosity.

Obviously, diol coordinates with salts of indium, magnesium salts, zinc salts, aluminum salts or salts of gallium, thus increasing thermal stability of salts of the metal.

Diol konkretne is limited and can be selected appropriately depending on the goal, but preferred arcangioli and dilkington. The number of carbon atoms contained in the diol, preferably 2-4. Diol having 5 or more carbon atoms has a low volatility and tends to remain in the formed metal oxide thin film (e.g., a thin film of oxide semiconductor), potentially reducing the density of the formed metallocene thin film (for example, a thin film of oxide semiconductor), after calcination. If the density of a thin film of oxide semiconductor decreases, the mobility of carriers may decrease, and may decrease the current.

Diol having 2-4 carbon atoms, has a boiling point from about 180°C to about 250°C. Thus, it evaporates in the process of calcination after coating liquid for coating with the formation of metal oxide thin films and harder for him to remain in the metal oxide thin film (e.g., a thin film of oxide semiconductor). In addition, since the diol has a viscosity from about 10 CPS to about 110 CPS, when the liquid coating with the formation of metal oxide thin film is applied by ink jet method, the diol has the effect of preventing the spreading when connecting the liquid coating to the substrate, etc.

Dio�ohms is preferably at least one, selected from diethylene glycol, 1,2-ethanediol, 1,2-PROPANEDIOL and 1,3-butanediol, taking into account the calcination temperature and the density of the metal oxide thin film after calcination (for example, a thin film of oxide semiconductor).

They can be used individually or in combination.

In the liquid coating with the formation of metal oxide thin films, the ratio of the metal salts and the amount of diol and simple glycol ether is not specifically limited and can be selected appropriately depending on the goal. The amount of metal salts is preferably 0.1 to 0.5 mol per 1 liter of diol and simple glycol ether. If it is less than 0.1 mol, the thickness of the formed metal oxide thin film after calcination becomes too small, potentially creating difficulty in the formation of a continuous film. In addition, to obtain the desired thickness, in some cases it is necessary to repeatedly perform the coating and drying. Whereas, if the number of metal salts of more than 0.5 mol, the inkjet head nozzles may be clogged if a higher frequency, if the liquid coating is applied by ink jet method.

<Other components>

Examples of other components include inorganic compounds of aluminum and reorgani�die compounds of gallium.

Inorganic compound of aluminum and an inorganic compound of gallium

The aluminum contained in the inorganic compound of aluminum or gallium contained in the inorganic compound of gallium, serve as a dopant, the replacement location India, and has the effect of doping with holes metal oxide thin film (e.g., a thin film of oxide semiconductor) obtained by coating liquid for coating with the formation of metal oxide thin films.

Inorganic compound aluminum is not specifically limited and can be appropriately selected depending on the goal. Examples mentioned above include oxanilate aluminum, aluminum halides, aluminum hydroxide and cyanide aluminum.

Examples of exocyclic aluminum include aluminum nitrate, aluminum sulfate, aluminum carbonate and aluminum phosphate.

Examples of the aluminum halides include aluminum chloride, aluminum bromide and aluminum iodide.

They may be anhydrides or hydrates mentioned above.

Inorganic gallium compound is not specifically limited and can be selected appropriately depending on the goal. Examples mentioned above include oxanilate arsenide, gallium halides, hydroxides of gallium and gallium cyanide.

Prima�s oxacyclic of gallium include gallium nitrate, the gallium sulfate, gallium carbonate and gallium phosphate.

Examples of the halides of gallium include gallium chloride, gallium bromide and iodide gallium.

They may be anhydrides or hydrates mentioned above.

They can be used individually or in combination.

The amount of inorganic aluminum compounds and inorganic compounds of gallium contained in the liquid coating with the formation of metal oxide thin film is not specifically limited and can be selected appropriately depending on the goal. The amount of (a) the number of aluminum ions and gallium ions is preferably 1-10% relative to the number of (A) ions of India.

<a Method of producing the liquid coating with the formation of metal oxide thin films>

A method of producing the liquid coating with the formation of metal oxide thin film is not specifically limited and can be selected appropriately depending on the goal. Examples mentioned above include a method in which a solution of salts of nitric acid in a solution of diol and salts of nitric acid in a simple glycol ether is prepared separately, and the resulting solutions are mixed with each other.

In particular, as example the following method.

First, nitrate, indium (In(NO )3·3H2O) and magnesium nitrate (Mg(NO3)2·6H2O are dissolved in a diol to prepare a solution of salts of nitric acid in the diol. Nitrate indium and magnesium nitrate can be dissolved to a concentration of 1 mol/l or more at room temperature with stirring diol (e.g., diethylene glycol, 1,2-ethanediol, 1,2-PROPANEDIOL or 1,3-butanediol). The time required for dissolution can be reduced by using heat.

Then the nitrate, indium (In(NO3)3·3H2O) and magnesium nitrate (Mg(NO3)2·6H2O) was dissolved in a simple glycol ether to prepare a solution of salts of nitric acid in a simple glycol ether. With stirring in a simple glycol ether, the monoethyl ether of ethylene glycol, monomethyl ether of ethylene glycol, monopropylene ether of ethylene glycol, monoisopropyl ether of ethylene glycol, monobutyl ether of ethylene glycol or monoisobutyl ether of ethylene glycol) nitrate, indium and magnesium nitrate can be dissolved to a concentration of 1 mol/l or more at room temperature. The time required for dissolution can be reduced by using heat.

Thereafter, the thus prepared solution of diol and a solution of glycol ether are mixed together in the desired mixing ratio.

Fluid�industry for coating with the formation of metal oxide thin film according to the invention are used respectively as the liquid coating with the formation of metal oxide thin films. In particular, the liquid coating with the formation of metal oxide thin films (liquid coating to form a thin film of oxide semiconductor), satisfying the expression (1) use respectively the liquid coating to form an active layer of a field effect transistor.

<Second liquid coating with the formation of metal oxide thin films>

As a variant embodiment of the second liquid coating with the formation of metal oxide thin films, different from the liquid coating of the present invention, in the form of example, the liquid coating to form a thin film of oxide semiconductor, comprising at least: an inorganic compound India; at least one inorganic magnesium compounds and inorganic compound of zinc; and a diol, and optionally further comprising other components and satisfying the expression (1).

Inorganic compound India, inorganic magnesium compound, inorganic compound of zinc and a diol in the liquid coating to form a thin film of oxide semiconductor are the same as the inorganic compound India, inorganic soedineniya, inorganic compound of zinc and a diol, in the above-described liquid coating with the formation of metal oxide thin films. Their preferred options of the incarnation and their amounts are the same as in the above-described liquid coating with the formation of metal oxide thin films.

Other components preferably are described above inorganic aluminum compounds, inorganic compounds of gallium, etc.

It is known that a film of indium oxide formed by a sputtering method, has a low resistivity is approximately

10-4Ω·cm by the addition of tin, zinc, gallium, etc., in the amount of approximately a few percent to approximately 20%. However, a film of indium oxide having such a low resistivity, can't work as an active layer of a field effect transistor.

If the liquid coating to form a thin film of oxide semiconductor satisfies the expression (1), a thin film of oxide semiconductor is formed by coating a liquid coating to form a thin film of oxide semiconductor, may be formed so as to have a volume resistivity, a thin film of oxide semiconductor can work�ü as an active layer of a field effect transistor.

If [B/(A+B)] is less than 0.25, then formed a thin film of oxide semiconductor has a too low volume resistivity. If this thin film of oxide semiconductor is used as the active layer of a field effect transistor, the active layer is always in a state of conduction regardless of the application of gate voltage, i.e., formed by field-effect transistor can operate as a transistor. Whereas, if [B/(A+B)] exceeds 0,65 formed by a thin film of oxide semiconductor has a too high volume resistivity. If such a thin film of oxide semiconductor is used as the active layer of a field effect transistor formed of a field effect transistor becomes a low emission levels in the state of on/off, i.e. does not show good characteristics of the transistor.

If a thin film of oxide semiconductor is used as the active layer of a field effect transistor used for excitatory circuits of the display, it requires a thin film of oxide semiconductor, which should have high carrier mobility and so-called normally open characteristics. In order to realize high carrier mobility and normally open characteristics, it is preferable volume resistivity �oncol film semiconductor regulate, to get to the range 10-2Ω·cm to 109Ohm·cm.

The object for plating (the object to which you want to apply the coating) is coated with a liquid coating to form a thin film oxide semiconductor (previously mentioned second liquid coating with the formation of metal oxide thin films), followed by drying and then calcining, whereby can be obtained a thin film of oxide semiconductor. The object for applying the coating, the coating method, the conditions of drying and calcination conditions are the same as described when you receive below a metal oxide thin film of the present invention.

(Metal oxide thin film)

Metal oxide thin film of the present invention was produced using the method, comprising: coating facility for coating liquid of the present invention for coating with the formation of metal oxide thin film; drying the object to the coating, which is deposited on the liquid coating; and calcining the dried object.

Examples of the metal oxide thin film includes a thin film of oxide semiconductor.

If the liquid coating with the formation of metal oxide thin film is a liquid for Nan�Senia coating with the formation of metal oxide thin films (liquid coating to form a thin film of oxide semiconductor), satisfies the above-mentioned expression (1), formed by a thin film of oxide semiconductor is used as the active layer of a field effect transistor.

The object for coating is not specifically limited and can be appropriately selected depending on the goal. Examples mentioned above include a glass substrate and a plastic substrate.

If a thin film of metal oxide is used as a thin film of oxide semiconductor, which serves as the active layer of a field effect transistor, the object of the application is, for example, the substrate or the insulation layer shutter. The shape, structure and size of the substrate is not specifically limited and can be selected depending on the goal. The material of the substrate is not specifically limited and can be selected depending on the goal. Examples of the substrate include a glass substrate or a plastic substrate.

Method of application liquid for coating is not specifically limited and can be appropriately selected depending on the goal. Examples mentioned above include the screen printing method, a coating method using a roll, a method of coating by dipping, the method of coating by centrifugation, inkjet JV�the FDS and nanoimprinting method. Among them, an inkjet method and nanoimprinting method are preferable because they can adjust the amount of coating used for coating. The result can be obtained metal oxide thin film of the desired shape. For example, the width of the channel may be formed as specified in obtaining field-effect transistor; in other words, can be obtained active layer having the desired shape. If using an inkjet method or a way of nanoimprint, the liquid coating can be applied even at room temperature. However, the substrate (the object of the coating) is preferably heated to about 40°C - about 100°C from the point of view of prevention of spreading of the liquid coating prior to application to the substrate.

The conditions under which performs drying is not specifically limited and can be selected depending on the purpose, provided that can be removed volatile components of the liquid coating with the formation of metal oxide thin films. In the drying process is not necessary to remove volatile components completely, i.e., the volatile components may be removed to such an extent that they do not slow calcination.

The temperature at which carry out the annealing is not specifically limited, and�and can be selected depending on the goal, provided that it is temperature that is equal to or higher than the temperature at which the formed indium oxide, magnesium, zinc, gallium or aluminum and which is equal to or lower than the temperature at which the deformed substrate (the object of the coating). It is preferably 300-600°C.

The atmosphere in which the calcination is carried out, is not specifically limited and can be selected depending on the goal. Her examples include the atmosphere containing oxygen, for example an atmosphere of oxygen or air. If the atmosphere in which the calcination is carried out, using an inert gas, for example nitrogen, the amount of oxygen contained in an educated metallocene thin film (for example, a thin film of oxide semiconductor) can be reduced to obtain a metal oxide thin film (e.g., a thin film of oxide semiconductor) having a low resistivity.

After calcination, with additional annealing calcined object in the atmosphere of air, inert gas or reducing gas can be enhanced further metal oxide thin film (e.g., a thin film of oxide semiconductor) in respect of electrical characteristics, reliability and uniformity.

The time of annealing is not specifically limit�lost, and it may be appropriately selected depending on the goal.

The average thickness of the formed metallookandfeel thin film (for example, a thin film of oxide semiconductor) is not specifically limited and can be selected depending on the purpose. It is preferably 1-200 nm, more preferably 5-100 nm.

The use of metal oxide thin film is not specifically limited and can be selected depending on the purpose. For example, if a thin film of metal oxide has a bulk resistivity less than 10-2Ω·cm, it can be used as transparent conducting thin films. If a thin film of metal oxide has a volume resistivity of 10-2Ω·cm to 109Ω·cm, it can be used as the active layer of a field effect transistor. If a thin film of metal oxide has a bulk resistivity greater than 109Ω·cm, it can be used as an antistatic thin films.

(Field effect transistor)

Field-effect transistor of the present invention contains at least a gate electrode, a source electrode, a drain electrode, the active layer and the insulating layer of the gate; and, if necessary, further contains other elements.

Field-effect transistor of the present�present invention can be obtained, for example, using the method of producing a field-effect transistor of the present invention.

<a shutter Electrode>

The gate electrode is not specifically limited and can be selected depending on the goal, provided that he is an electrode for the application of gate voltage.

The material of the gate electrode is not specifically limited, and may be selected appropriately depending on the goal. Examples mentioned above include: metals such as platinum, palladium, gold, silver, copper, zinc, aluminum, Nickel, chromium, tantalum, molybdenum, and titanium; alloys thereof and mixtures thereof. Additionally, the examples include a conductive oxide, e.g., indium oxide, zinc oxide, tin oxide, gallium oxide and niobium oxide; their complex compounds and mixtures thereof.

The average thickness of the gate electrode is not specifically limited and may be appropriately selected depending on the goal. It is preferably 40 nm to 2 μm, more preferably 70 nm to 1 μm.

<an Insulating layer shutter>

The insulating layer of the gate is not specifically limited and can be appropriately selected depending on the goal, provided that he is an insulating layer formed between the gate electrode and the active layer.

M�material gate insulating layer is not specifically limited to, and it may be appropriately selected depending on the goal. His examples include inorganic insulating materials and organic insulating materials.

Examples of inorganic insulating materials include silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, yttrium oxide, lanthanum oxide, hafnium oxide, zirconium oxide, silicon nitride, aluminum nitride and mixtures thereof.

Examples of the organic insulating materials include polyimides, polyamides, polyacrylates, polyvinyl alcohols and Novolac resins.

The average thickness of the gate insulating layer is not specifically limited and may be appropriately selected depending on the goal. It is preferably 50 nm - 3 μm, more preferably 100 nm -1 µm.

<the source Electrode and the drain electrode>

The source electrode or the drain electrode is not specifically restricted and can be appropriately selected depending on the purpose, provided that they are the electrodes for the removal of the current.

The material of the source electrode or the drain electrode is not specifically limited and can be selected depending on the goal. His examples include materials that are the same as those described above for the gate electrode.

The average thickness of the electro�and the source or drain electrode is not specifically limited to, and it may be appropriately selected depending on the goal. It is preferably 40 nm to 2 μm, more preferably 70 nm to 1 μm.

<the Active layer>

The active layer is an active layer made of oxide semiconductor is formed between the source electrode and the drain electrode, and the active layer formed of an oxide semiconductor formed by coating a liquid coating of the present invention with the formation of metal oxide thin films.

The average thickness of the active layer is not specifically limited and may be appropriately selected depending on the goal. It is preferably 1 nm to 200 μm, more preferably 5 nm - 100 μm.

The design of the field-effect transistor is not specifically limited and may be selected appropriately depending on the goal. Examples mentioned above include construction type bottom gate/bottom contact (Fig.1), construction type bottom gate/top contact (Fig.2), construction type top gate/bottom contact (Fig.3) and construction type top gate/top contact (Fig.4).

Fig.1-4 position 1 denotes a substrate, 2 denotes a gate electrode, 3 denotes an insulating layer shutter, 4 denotes a source electrode, 5 denotes an electrode �current and 6 denotes an active layer.

[The second field-effect transistor]

As a variant embodiment of the second field-effect transistor, different from the field-effect transistor of the present invention, in the form of examples show field-effect transistor, which is the same as the field effect transistor of the present invention, except that the use described above, the second liquid coating with the formation of metal oxide thin films instead of liquid the present invention for coating with the formation of metal oxide thin films.

Field-effect transistor of the present invention and the second field-effect transistor can be used appropriately for field-effect transistors in the pixel control circuits and logic circuits of liquid crystal displays, organic electroluminescent EL (electroluminescence) displays, electrochromic displays, etc.

(Method of producing a field-effect transistor)

A method of producing a field effect transistor according to the invention (the first method of obtaining includes:

the stage of formation of the gate electrode with the formation of the gate electrode on the substrate;

the stage of formation of the gate insulating layer with the formation of the gate insulating layer;

stage of formation of the source electrode and the drain electrode with the formation of the source electrode and the drain electrode on isolaz�the main objective of the shutter layer, so that the source electrode and the drain electrode have a certain distance from each other to form between them a channel region; and

the stage of formation of the active layer to form an active layer of an oxide semiconductor on an insulating layer of the gate in the channel region between the source electrode and the drain electrode.

Another method of producing a field-effect transistor (the second method of receipt) of the present invention includes:

stage of formation of the source electrode and the drain electrode with the formation of the source electrode and the drain electrode on the substrate, so that the source electrode and the drain electrode have a certain distance from each other to form between them a channel region;

the stage of formation of the active layer to form an active layer of an oxide semiconductor on the substrate in the channel region between the source electrode and the drain electrode

the stage of formation of the gate insulating layer with the formation of the gate insulating layer on the active layer;

the stage of formation of the gate electrode with the formation of the gate electrode on the insulating layer of the gate.

<the First method of obtaining>

Next will be described the above first method of receipt.

Substrate

Shape, design and size of the substrate is not specifically limited and can be selected by sootvetstvuyuschaya depending on the goal.

The material of the substrate is not specifically limited and can be appropriately selected depending on the goal. Examples of the substrate include a glass substrate and a plastic substrate.

The glass substrate is not specifically limited and can be chosen depending on the goal. Her examples include not containing alkali metals glass substrate and silicon glass substrate.

The plastic substrate is not specifically limited and can be appropriately selected depending on the goal. Her examples include polycarbonate substrate (PC), polyimide (PI) substrate, polyethylene terephthalate (PET) substrate and polietilentereftalatnoy (PEN) substrate.

In particular, preferably the substrate is pre-treated by washing with the use of oxygen plasma, UV-ozone and UV radiation from the point of view of cleaning the surface of the substrate and improve adhesion to the surface.

The stage of formation of the gate electrode

The stage of formation of the gate electrode is not specifically restricted and can be appropriately selected depending on your goals, provided that he is the stage of formation of a gate electrode on the substrate. Examples of the stages of the formation of the gate electrode comprises (i) a stage of education film on�OSU, for example, a sputtering method, or the method of coating by immersion and patterning the film by photolithography and (ii) the phase of the direct formation of a film having the desired shape, by means of a printing process, for example, inkjet, nanoimprinting or gravure printing.

The stage of formation of the insulating layer of the gate

The stage of formation of the gate insulating layer is not specifically restricted and can be appropriately selected depending on your goals, provided that he is the stage of formation of the gate insulating layer on the gate electrode.

Examples of the stage of education gate insulating layer comprises (i) a stage of education film using, for example, a sputtering method, or the method of coating by immersion and patterning the film by photolithography and (ii) the phase of the direct formation of a film having the desired shape, by means of a printing process, for example, inkjet, nanoimprinting or gravure printing.

Stage of formation of the source electrode and the drain electrode

Stage of formation of the source electrode and drain electrode are not specifically limited and can be appropriately selected depending on your goals, provided that he is the stage of formation of the source electrode and the drain electrode on the insulating layer, so that h�of them have at a certain distance from each other. Examples of the stage of formation of the source electrode and the drain electrode include (i) the stage of formation of the film using, for example, a sputtering method, or the method of coating by immersion and patterning the film by photolithography and (ii) the phase of the direct formation of a film having the desired shape, by means of a printing process, for example, inkjet, nanoimprinting or gravure printing.

The stage of formation of the active layer

The stage of formation of the active layer is not specifically limited and can be appropriately selected depending on your goals, provided that it is a step in the coating liquid for coating of the present invention with the formation of metal oxide thin film to form the active layer of an oxide semiconductor on an insulating layer of the gate in the channel region between the source electrode and the drain electrode.

At the stage of formation of the active layer, preferably by adjusting accordingly the ratio [B/(A+B)], where A denotes the number of ions of India, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating with the formation of metal oxide thin film, an oxide semiconductor is controlled by at least one of the specific volume resistivity, mobility but�the nd density media. As a result, it is possible to obtain a field-effect transistor having desirable characteristics (e.g., emission levels in the States on / off).

At the stage of formation of the active layer is preferably a liquid for coating with the formation of metal oxide thin film comprises diol and by adjusting appropriately the relations of the simple components of the mixture of glycol ether and diol contained in the liquid coating with the formation of metal oxide thin films, control the viscosity of the liquid coating with the formation of metal oxide thin films. As a result, the liquid coating is excellent in ability to apply and can be obtained field-effect transistor having a channel formed in good condition.

Method of coating liquid for coating with the formation of metal oxide thin film to form an oxide semiconductor is not specifically limited and can be appropriately selected depending on the goal. Examples mentioned above include a method in which a substrate is coated with a liquid coating with the formation of metal oxide thin film, followed by drying and then calcining.

This method of coating is not specifically limited to � it can be suitably selected depending on the goal. Examples mentioned above include the screen printing method, a coating method using a roll, a method of coating by immersion, the method of coating by centrifugation, inkjet method and nanoimprinting method. Among them, an inkjet method and nanoimprinting method are preferable because they can manage the amount of applied liquid coating. As a result the width of the channel upon receipt of a field effect transistor may be formed, for example, as specified; in other words, it is possible to obtain an active layer with a desired shape.

The conditions under which performs drying is not specifically restricted and can be appropriately selected depending on the goal, provided that the volatile components in the liquid coating with the formation of metal oxide thin films can be removed. Moreover, when drying the volatile components need not be completely removed, i.e., the volatile components may be removed to such an extent that they do not hinder the calcination.

The temperature at which the calcination is carried out, is not specifically limited and can be appropriately selected depending on the goal. It is preferably 300°C-600°C.

In the first method of producing the order in which about�odat stage of formation of the source electrode and the drain electrode and the stage of formation of the active layer, can be anything; i.e., the stage of formation of the active layer can be carried out after the stage of formation of the source electrode and the drain electrode or the stage of formation of the source electrode and the drain electrode can be carried out after the stage of formation of the active layer.

In the first method of obtaining, when the stage of formation of the active layer is carried out after the stage of formation of the source electrode and the drain electrode, can be obtained field-effect transistor type, the bottom gate/bottom contact.

In the first method of obtaining, when the stage of formation of the source electrode and the drain electrode is performed after the step of formation of the active layer, can be obtained field-effect transistor type, the bottom gate/top contact.

Referring to Fig.5A-5D, next will be described a method of producing a field effect transistor type bottom gate/bottom contact.

First, a conductive film made of, for example, made of aluminum, formed on the substrate 1 (e.g. glass substrate) using, e.g., sputtering method to form a conductive film pattern by etching to form a gate electrode 2 (Fig.5A).

Next, the insulating layer 3 shutter, made of, for example, of SiO2form on the gate electrode 2 and the substrate 1, for example, by a sputtering method so as to coat the gate electrode 2 (Fig.5B).

Next, a conductive film made of, �of primer, ITO, is formed on the insulating layer 3 of the shutter, for example, by a sputtering method to form a conductive film pattern by etching to form a source electrode 4 and drain electrode 5 (Fig.5C).

Next, the liquid coating with the formation of metal oxide thin film is applied on the insulating layer 3 of the shutter, for example, an inkjet method so as to coat an area of the channel formed between the source electrode 4 and drain electrode 5, followed by heat treatment to thereby form an active layer 6 of oxide semiconductor (Fig.5D).

Using the above procedures have field-effect transistor

<the Second way of getting>

Next will be described the above second method.

Substrate

The substrate is not specifically restricted and can be appropriately selected depending on the goal. Her examples include substrates that are the same as shown in the example in the first method of receipt.

Stage of formation of the source electrode and the drain electrode

Stage of formation of the source electrode and drain electrode are not specifically limited and can be appropriately selected depending on your goals, provided that he is the stage of formation of the source electrode and the drain electrode on the substrate, so that �x feature at a certain distance from each other. Examples of the stage of formation of the source electrode and the drain electrode comprise the steps are the same as shown in the example as the stage of formation of the source electrode and the drain electrode of the first method of receipt.

The stage of formation of the active layer

The stage of formation of the active layer is not specifically limited and can be appropriately selected depending on your goals, provided that it is a step in the coating liquid for coating of the present invention with the formation of metal oxide thin film to form the active layer of an oxide semiconductor on the substrate in the channel region between the source electrode and the drain electrode.

Method of coating liquid for coating with the formation of metal oxide thin film to form the active layer of the oxide semiconductor is not specifically limited and can be appropriately selected depending on the goal. Examples of the stages forming the active layer, includes the steps, which are the same as shown in the example of the stages of formation of the active layer of the first method of receipt.

At the stage of formation of the active layer, preferably by adjusting accordingly the ratio [B/(A+B)], where A denotes the number�STV ions India, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating by the formation of metal oxide thin film, an oxide semiconductor is controlled by at least one of the specific volume resistivity, carrier mobility and carrier density. As a result, it is possible to obtain a field-effect transistor having desirable characteristics (e.g., emission levels in the States on / off).

At the stage of formation of the active layer liquid coating with the formation of metallocene thin film preferably contains a diol, and correcting accordingly the relations of the simple components of the mixture of glycol ether and diol contained in the liquid coating with the formation of metal oxide thin films, adjust the viscosity of the liquid coating with the formation of metal oxide thin films. As a result, the liquid coating is superior in ability to the application, and provide a field-effect transistor having a channel in good condition.

The stage of formation of the insulating layer of the gate

The stage of formation of the gate insulating layer is not specifically limited and can be appropriately selected depending on the goal, provided that he is the stage obra�hardware gate insulating layer on the active layer.

Examples of the stages of the formation of the gate insulating layer includes the steps that are the same as given as an example of the stages of the formation of the gate insulating layer of the first method of receipt.

The stage of formation of the gate electrode

The stage of formation of the gate electrode is not specifically limited and may be appropriately selected depending on the purpose, provided that it is a stage of formation of a gate electrode on an insulating layer shutter. Examples of the phase formation of the gate electrode includes the steps, which is the same as shown in the example of the stages of formation of a gate electrode of the first method of receipt.

In the second method of producing the order in which you perform the stage of formation of the source electrode and the drain electrode and the stage of formation of the active layer, can be any, i.e. the stage of formation of the active layer can be performed after the stage of formation of the source electrode and the drain electrode or the stage of formation of the source electrode and the drain electrode can be performed after the stage of formation of the active layer.

In the second method of obtaining, when the stage of formation of the active layer is carried out after the stage of formation of the source electrode and the drain electrode, it is possible to obtain a field-effect transistor type top gate/bottom contact.

In the second method of obtaining, when the stage of formation of the source electrode and the drain electrode is performed after the step of formation of the active layer, it is possible to obtain a field-effect transistor type top gate/top contact.

[Second method of producing a field-effect transistor]

As a variant embodiment of the second method of producing a field-effect transistor, different from the method of the present invention, in the form of an example method of producing a field effect transistor, which is the same as the method of producing a field-effect transistor of the present invention, except that instead of the liquid of the present invention for coating with the formation of metal oxide thin films using the above second liquid coating with the formation of metal oxide thin films.

Examples

The present invention will be described further by means of Examples, which are not to be construed as limiting the present invention.

Example 1

<Preparation of the liquid coating with the formation of metal oxide thin films>

First, 3,55 g of nitrate, indium (In(NO3)3·3H2O) and 1.28 g (Mg(NO3)2·6H2O) were weighed and placed in a beaker. Then in a beaker was added 80 ml of monomethyl ether of ethylene glycol, followed by mixing and dissolving�the ions at room temperature, to thereby prepare a liquid for the coating with the formation of metallocene thin films.

In Tables 2-1 and 2-2 show the ratio [B/(A+B)], (where A denotes the number of ions of India, and In denotes the sum of the number of magnesium ions and the number of zinc ions), the number of simple glycol ether (mass %), the amount of metal salts to 1 liter of diol and simple glycol ether, and the ratio (C)/(A) (where A denotes the number of ions India, and denotes the sum of the number of aluminum ions and gallium ions) obtained in the liquid coating with the formation of metal oxide thin films.

<Obtaining a field effect transistor>

The formation of the gate electrode

By spraying at a constant current was formed on the molybdenum film on a glass substrate to have a thickness of about 100 nm. Subsequently, on the thus formed film deposited photoresist, followed by preliminary zadovolenyam, exhibiting with the help of the device exposure and manifestation, to thereby form a photoresist pattern having the same pattern as the pattern of the gate electrode, which should be formed. In addition, performing etching using the Etchant containing phosphoric acid, nitric acid and acetic acid, to thereby remove the sphere� molybdenum film, where was formed a photoresist pattern. Then removed the photoresist pattern to form a gate electrode.

The formation of the insulating layer of the gate

By using RF sputtering was formed SiO2film on the gate electrode and the glass substrate to have a thickness of about 300 nm. Subsequently, on the thus formed film deposited photoresist, followed by preliminary zadovolenyam, exhibiting with the help of the device exposure and manifestation, to thereby form a photoresist pattern having the same pattern as the pattern of the insulating layer of the gate that needs to be educated. In addition, etching was performed using a buffer solution of hydrofluoric acid, to thereby remove the field SiO2film, where there was formed a photoresist pattern. Then removed the photoresist pattern to form an insulating layer of a gate.

The formation of the source electrode and the drain electrode

By spraying at a constant current was formed ITO film (In2O3-SnO2(5 mass%) as a transparent conductive film formed on the insulating layer of the shutter, to have a thickness of approximately 100 nm. Subsequently, on the thus formed ITO film deposited photoresist, followed preliminary sadulleva�education, exposure using the device for exposure and manifestation, to thereby form a photoresist pattern having the same pattern as the pattern of the source electrode and the drain electrode, to be formed. Also carried out the etching using the Etchant on the basis of oxalic acid so as to remove the area of the ITO film, where there was formed a photoresist pattern. Thereafter, the photoresist pattern was removed to form a source electrode and a drain electrode of an ITO film. Here the channel width defined as the width of the source electrode, was set equal to 50 μm and the channel length defined as the distance between the source electrode and the drain electrode, was set equal to 10 microns.

The formation of the active layer

Using an inkjet device, the liquid coating with the formation of metal oxide thin films deposited on a channel between the source electrode and the drain electrode.

The substrate was dried for 10 min on a hot plate heated to 120°C, and then calcined in air at 500°C for 1 hour. In addition, the substrate was annealed in air at 300°C for 3 hours to thereby obtain the active layer. It was found that the thickness of the active layer in the channel was approximately 20 nm.

Using the left during� procedure was obtained a field-effect transistor.

<Evaluation>

The state in the formation of the channel (the ability to cover)

Observing through an optical microscope, the spreading of the liquid coating with the formation of metal oxide thin films, if the manufacture of a field effect transistor it was applied using an inkjet device, the condition in the formation of the channel was evaluated according to the following evaluation criteria. The results are shown in Tables 3-1 and 3-2.

A. the Active layer is spread within a space between the source electrode and the drain electrode and does not extend outside of the gate electrode (see Fig.6).

V. the Active layer from leaking outside of the space between the source electrode and the drain electrode and left the gate electrode (see Fig.7).

Volume resistivity

Using the analyzer of semiconductor S (manufactured by Agilent Technologies Co.), applied voltage from 0 V to ±20 V between the source electrode and the drain electrode of the obtained field-effect transistor, and measured the current two-terminal method to measure the volume resistivity of the active layer. The results are shown in Tables 3-1 and 3-2.

The carrier mobility and the ratio of levels in the States of enabled/disabled

Using analyzer features (manufactured by Agilent Technologies Co., the semiconductor parameter analyzer S) changes�Yali field-effect transistor, obtained in Example 1 to obtain the relationship between gate voltage Vgs and a current source-drain Ids observed when the voltage of the source-drain was set to 20 V. the Results are shown graphically in Fig.8. From Fig.8, it was found that there were obtained good characteristics of the transistor.

The carrier mobility was calculated in the saturation region, and calculated the ratio of levels in the States on/off. Moreover, the emission levels in the state of on/off corresponded to the value Ids at 30 V. the Results are shown in Tables 3-1 and 3-2.

(Examples 2-35 and Reference Example 1)

<Preparation of the liquid coating with the formation of metal oxide thin films>

Repeating the procedure of Example 1, except that the liquid composition for coating with the formation of metal oxide thin films were changed as shown in Tables 1-1 and 1-2, to thereby prepare a liquid coating with the formation of metal oxide thin films of Examples 2-35 and Reference Example 1.

In Tables 2-1 and 2-2 shows the ratio [B/(A+B)], the number of simple glycol ether (%by mass), the amount of metal salts to 1 liter of diol and simple glycol ether and the ratio (C)/(A) (%) (where A denotes the number of ions India, and denotes the sum of the number of aluminum ions and ions Gal�ia) obtained in the liquid coating with the formation of metal oxide thin films.

<Receipt and evaluation of the field-effect transistor>

Repeating the procedure of Example 1, except that used each of the fluids coating of Examples 2-23 and 28-35, to thereby obtain and evaluate field-effect transistor. The results are shown in Tables 3-1 and 3-2.

<the Ratio between the specific volume resistance and [B/(A+B)]>

Fig.9 shows the values of specific volume resistivity in comparison with the ratio [B/(A+B)] for each of the fluids coating of Examples 1-27 (where A denotes the number of ions of India, and In denotes the sum of the number of magnesium ions and the number of zinc ions). As is clear from Fig.9, it was confirmed that the calcined thin film of oxide semiconductor can be adjusted in relation to the specific volume resistivity by adjusting the ratio [B/(A+B)] for the liquid coating with the formation of metal oxide thin films.

(Comparative Example 1)

<Preparation of the liquid coating with the formation of metal oxide thin films>

To assess the fluid composition described in JP-A 2009-177149, 3,55 g of nitrate India and 1.26 g of magnesium nitrate was added to a mixture comprising 40 ml of water and 40 ml of ethanol. The resulting mixture was stirred for dissolution to prepare a liquid for the coating with the formation of metallocene� thin films.

<Receipt and evaluation of the field-effect transistor>

The thus prepared liquid coating with the formation of metal oxide thin films used to obtain the field-effect transistor in the same way as in Example 1. However, the liquid coating with the formation of metal oxide thin film was unsatisfactory in relation to the ability of the coating, and thus, the condition for formation of the channel was unsatisfactory, resulting in a field-effect transistor could not be assessed.

(Comparative Example 2)

<Preparation of the liquid coating with the formation of metal oxide thin films>

To evaluate the liquid coating with the formation of metal oxide thin film described in JP-A 06-96619, 3,55 g of nitrate India and 0.26 g of magnesium nitrate was added to a mixture containing 4.0 ml of acetylacetone and 0.63 ml of glycerol, the resulting mixture was stirred for dissolution at room temperature to thereby prepare a liquid coating with the formation of metal oxide thin films.

<Receipt and evaluation of the field-effect transistor>

Despite the fact that the liquid coating with the formation of metal oxide thin films used to obtain the field-effect transistor in the same manner as in If�'ere 1, the solvent too quickly dried, thereby causing clogging of inkjet devices. As a result inkjet device could not apply the liquid coating to form a thin film. Thus, the coating could not be obtained, nor to evaluate.

In Tables 1-1 and 1-2 nitrate India is In(NO3)3·3H2O, sulfate India is In2(SO4)3·9H2O, chloride India is InCl3·4H2O, magnesium nitrate is Mg(NO3)2·6H2O, magnesium sulfate is MgSO4·7H2O, the magnesium chloride is MgCl2·6H2O, nitrate of zinc is Zn(NO3)2·6H2O zinc sulfate is ZnSO4·7H2O, chloride of zinc is ZnCl2·H2O, the aluminum nitrate is Al(NO3)3·9H2O and nitrate gallium is Ga(NO3)3·3H2O.

Table 1-2 (*1) means a mixture containing 40 ml of water and 40 ml of ethanol, and (*2) means a mixture containing 4.0 ml of acetylacetone and 0.63 ml of glycerin.

Table 2-1
B/(A+B)The amount of glycol ether
(%�asse)
The amount of metal salts to 1 liter of diol and simple glycol ether (mol)The ratio C/A (%)
the sum With the number
ions of aluminum
and number
ions of gallium to
the number of ions And
India
Examples10,3394,10,190
20,2545,70,170
30,3333,80,190
40,5022,00,250
50,6510,60,360
60,3344,00,190
70,3344,00,19 0
80.3346,10,190
90,3344,40,190
100,3343,90,190
110,3343,80,190
120,3343,70,190
130,3343,50,190
140,3345,40,190
150,33of 45.30,190
160,25 45,60,170
170,5044,50,250
180,6543,30,360
190,3445,40,195
200,3445,40,195
210,5144,50,255
220,5144,60,255
230,5044,60,250

240,2045,8 0,160
250,7043,10,420
260,2045,70,160
270,70the 42.60,420

Table 2-2
B/(A+B)The amount of glycol ether
(mass%)
The amount of metal salts to 1 liter of diol and simple glycol ether (mol)The ratio C/A (%)
the sum With the number
ions of aluminum
and number
ions of gallium to
the number of ions And
India
Examples280,3343,80,190
290,3345,80,19 0
300,3343,70,190
310,3345,70,190
320,33over 45.50,190
330,3345,60,190
340,3345,40,190
350,3342,70,190
Reference example10,330,00,190
Comparative
example
10,330,0-0
20,090,0-0

Table 3-1
Where was formed the channelVolume resistivity (Ω·cm)The carrier mobility (cm2/volume/(C)The emission levels in the state of on/off
Examples1A4×1020,18the 6.5×107
2A4×1010,3of 1.5×108
3A6×1020,24of 1.2×108
4A5×1030,087,2×106
5A2×1050,003a 3.2×105
6A4×1020,241,0×108
7A4×1020,28,8×107
8A4×1020,18of 8.5×107
9A4×1020,198,6×107
10A6×1020,25of 1.1×108
11A3×1020,156,0×107
12A5×1020,22of 9.4×107
13A5×1020,219,0×107
14A6×1020,231,0×108

15A2×1020,83of 1.4×108
16A4×1000,54of 1.5×108
17A1×1020,96of 1.8×108
18A4×1020,2of 1.5×105
19A1×1030,14of 5.8×107
20 A2×1030,167,1×107
21A4×1020,71of 7.7×107
22A5×1020,63the 6.5×107
23A1×1030,16of 7.4×107

Comparative example
Table 3-2
Where was formed the channelVolume resistivity (Ω·cm)The carrier mobility
(cm2/volume/(C)
The emission levels in the state of on/off
Examples28A5×1020,24of 8.5×107
29A 4×1020,178,8×107
30A3×1020,199,1×107
31A6×1020,21of 7.5×107
32A4×1020,29,5×107
33A4×1020,18of 7.4×107
34A5×1020,219,3×107
35A4×1020,221,0×108
Reference example1A7×1020,26of 1.1×108
1In---
2----

The liquid coating of the present invention of Examples 1-23 and 28-35 and liquid for the coating of Reference Example 1 were superior in ability to the coating and could provide good results with respect to the location where it was formed channel. In addition, field-effect transistors that use as their active layer of an oxide semiconductor formed by coating liquids for coating with the formation of metal oxide thin film, the active layer had a volume resistivity corresponding to the active layer of a field effect transistor, and demonstrated high carrier mobility and high levels in the States on/off. Thus, these field-effect transistors showed good characteristics of the transistor.

In Comparative Example 1, the liquid coating to form a thin film of oxide semiconductor was inappropriate for their ability to coating, and ka�al was formed unsatisfactory. As a result, the field effect transistor could not be assessed.

Fluid for the deposition of metal oxide thin-film coatings of Examples 24 and 26 were superior in ability to coating. As shown in Table 4, below, formed metal oxide thin film had a low volume resistivity and was a metal-oxide thin films suitable for use as, for example, transparent conductive thin films.

Fluid for the deposition of metal oxide thin-film coatings of Examples 25 and 27 were relatively superior ability to spray. As shown in Table 4, below, formed metal oxide thin film had a relatively high volume resistivity and was a metal-oxide thin films suitable for use as, for example, antistatic thin films.

Table 4
Volume resistivity (Ω·cm)
Examples242×10-3
252×109
26 5×10-3
271×109

It should be noted that the volume resistivity shown in Table 4 were measured in the same manner as in the measurement of the specific volume resistivity in Example 1.

(Example 36)

The mixing ratio of a simple glycol ether and diol was changed to adjust the viscosity of the fluid for the deposition of metal oxide thin film coatings.

In particular, monomethyl ether of ethylene glycol (viscosity: about 1.6 CPS), 1,2-PROPANEDIOL (viscosity: about 40 CPS) nitrate, indium (In(NO3)3·3H2O) and magnesium nitrate (Mg(NO3)2·6H2O) was used to prepare the fluid for the deposition of metal oxide thin-film coating. With this preparation the mixing ratio of India and nitrate magnesium nitrate in a liquid for applying a metal oxide thin film coating was adjusted so that the number of ions In:the number of Mg ions was 2:1, and the concentration of ions In were 0 mol/l, 0.25 mol/l, 0.5 mol/l, 1 mol/l 1.5 mol/L. Then the ratio of the components of a mixture of monomethyl ether of ethylene glycol (X ml) and 1,2-PROPANEDIOL (Y ml) variously changed. The results are shown in Fig.10. It is confirmed that it is possible to adjust the viscosity of liquids on�Yesenia metal oxide thin film coating, having different ion concentrations India, changing the ratio in a mixture of simple glycol ether and diol contained in the fluid.

The list of reference positions

1. Substrate

2. The electrode paddle

3. The insulating layer of the gate

4. The source electrode

5. The drain electrode

6. The active layer.

1. The liquid coating for the formation of metal oxide thin films, including:
inorganic compound India;
at least one of an inorganic magnesium compounds and inorganic zinc compounds; simple glycol ether and a diol,
moreover diol selected from at least one of diethylene glycol, 1,2-PROPANEDIOL and 1,3-butanediol.

2. The liquid coating for the formation of metal oxide thin film according to claim 1,
in which inorganic compound India is at least one selected from the group consisting of nitrate India, sulfate, indium chloride and indium;
in which the inorganic magnesium compound is at least one selected from the group consisting of magnesium nitrate, magnesium sulfate and magnesium chloride; and
in which the inorganic compound of zinc is at least one selected from the group consisting of zinc nitrate, zinc sulfate and zinc chloride.

3. The liquid coating for the formation of the metal oxide�coy film according to claim 1, and the liquid coating for the formation of metal oxide thin film satisfies the following expression (1):

where And denotes the number of ions India, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating for the formation of metal oxide thin films.

4. The liquid coating for the formation of metal oxide thin film according to claim 1, further comprising at least one inorganic aluminum compounds and inorganic compounds of gallium.

5. Metal oxide thin film obtained by the method, which includes:
the object for coating the coating liquid for the coating for the formation of metal oxide thin film;
the drying of the object to the coating, which was covered by a liquid coating; and
calcination of the dried object for coating formation on top of metal oxide thin films,
the liquid coating for the formation of metal oxide thin film includes:
inorganic compound India;
at least one of an inorganic magnesium compounds and inorganic zinc compounds; simple glycol ether and a diol,
moreover diol selected from at least one indiatelephone, 1,2-PROPANEDIOL and 1,3-butanediol.

6. Field-effect transistor, including:
a gate electrode configured for the application of gate voltage,
the source electrode and the drain electrode, configured to remove the current
an active layer formed of an oxide semiconductor, and disposed between the source electrode and the drain electrode,
the insulating layer of the gate formed between the gate electrode and the active layer,
this oxide semiconductor is formed by coating a liquid coating for the formation of metal oxide thin films, and
the liquid coating for the formation of metal oxide thin film includes:
inorganic compound India;
at least one of an inorganic magnesium compounds and inorganic zinc compounds; simple glycol ether and a diol,
moreover diol selected from at least one of diethylene glycol, 1,2-PROPANEDIOL and 1,3-butanediol.

7. A method of producing a field effect transistor comprising: a gate electrode on a substrate,
the formation of a gate insulating layer on the gate electrode; the formation of the source electrode and the drain electrode on the insulating layer of the gate so that the source electrode and the drain electrode are spaced apart to form between them possess�th channel; and
the formation of the active layer formed from an oxide semiconductor, on the insulating layer of the gate in the channel region between the source electrode and the drain electrode,
thus the formation of the active layer coating the gate insulating layer liquid coating for the formation of metal oxide thin film to thereby form the active layer of an oxide semiconductor, and
the liquid coating for the formation of metal oxide thin film includes:
inorganic compound India;
at least one of an inorganic magnesium compounds and inorganic zinc compounds; simple glycol ether and a diol,
moreover diol selected from at least one of diethylene glycol, 1,2-PROPANEDIOL and 1,3-butanediol.

8. A method of producing a field effect transistor according to claim 7, which regulate at least one of the volume resistivity, carrier mobility and carrier density of the oxide semiconductor by adjusting the ratio [B/(A+b)], where A denotes the number of ions of India, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating for the formation of metal oxide thin films.

9. A method of producing a field effect transistor according to claim 7, in which the viscosity of the liquid coating for education�ia metal oxide thin films regulate, correcting the simple ratio of glycol ether and diol contained in the liquid coating for the formation of metal oxide thin films.

10. A method of producing a field effect transistor, including:
the formation of the source electrode and the drain electrode on the substrate so that the source electrode and the drain electrode are spaced from each other to form a channel region between them;
the formation of the active layer formed of an oxide semiconductor on the substrate in the channel region between the source electrode and the drain electrode;
the formation of a gate insulating layer on the active layer; and the formation of the gate electrode on the insulating layer of the gate, while the formation of the active layer is a coating substrates by a liquid coating for the formation of metal oxide thin film to thereby form the active layer of an oxide semiconductor, and
the liquid coating for the formation of metal oxide thin film includes: inorganic compound India;
at least one of an inorganic magnesium compounds and inorganic zinc compounds; simple glycol ether and a diol,
moreover diol selected from at least one of diethylene glycol, 1,2-PROPANEDIOL and 1,3-butanediol.

11. A method of producing a field effect transistor according to claim 10, in �oterom regulate at least one of the volume resistivity, carrier mobility and the carrier density of the oxide semiconductor by adjusting the ratio [B/(A+b)], where A denotes the number of ions of India, and In denotes the sum of the number of magnesium ions and the number of zinc ions in the liquid coating for the formation of metal oxide thin films.

12. A method of producing a field effect transistor according to claim 10, wherein the viscosity of the liquid coating for the formation of metal oxide thin film is adjusted by adjusting the ratio of a simple glycol ether and diol contained in the liquid coating for the formation of metal oxide thin films.



 

Same patents:

FIELD: electricity.

SUBSTANCE: semiconductor device comprises a thin-film transistor comprising a gate bus, the first insulating film, an oxide-semiconductor layer in the form of an island, the second insulating film, a source bus, a drain electrode and a passivating film, and also a contact site, comprising the first connection element, made of the same conducting film as the gate bus, the second connecting element made from the same conducting film as the source bus and the drain electrode, and the third connection element formed on the second connection element. The second connection element contacts with the first connection element in the first window provided in the first and second insulating films, the third connection element contacts with the second connection element in the second window provided in the passivating film, and the second connection element covers the end surfaces of the first insulating film and the second insulating film in the first window, but does not cover the end surface of the passivating film in the second window. As a result the conical shape of the contact hole of the contact site may be controlled with high accuracy.

EFFECT: reduced damage of a mask.

17 cl, 14 dwg

FIELD: electrical engineering.

SUBSTANCE: semiconductor device includes thin-film diode and protection circuit with protective diode. Thin-film diode includes semiconductor layer with the first, second zones and channel zone, gate electrode, the first electrode connected to the first zone and gate electrode and the second electrode connected to the second zone. When conductivity type of thin-film diode is n-type then anode electrode of the protective diode is connected to the line which is connected either to gate electrode or to the first electrode of thin-film diode. When conductivity type of thin-film diode is P-type then cathodic electrode of the protective diode is connected to the line which is connected either to gate electrode or to the first electrode of thin-film diode. Protective circuit does not include other diodes which are connected to the line so that current direction is opposite to the protective diode.

EFFECT: deterioration of thin-film diode properties can be decreased when size of the circuit is minimised.

12 cl, 37 dwg

FIELD: electricity.

SUBSTANCE: thin-film transistor comprises the first capacitor, comprising an area, in which the first electrode of the capacitor connected with an electrode of source, and the second electrode of the capacitor are arranged one on the other in direction of thickness at opposite sides of the first layer of a dielectric, formed between them, the second capacitor, comprising an area, in which the third and fourth electrodes of the capacitor are arranged one above the other in direction of thickness at the opposite sides of the second layer of the dielectric, formed between them, four output buses, stretching from the appropriate electrode of the capacitor in a plane direction, the first connection crossing the second and fourth output buses, when looking in direction of thickness, and the second connection crossing the first and third output buses, when looking in direction of thickness, besides, the second electrode of the capacitor and the gate electrode are connected to each other via the second output bus, the third electrode of the capacitor and the source electrode are not connected to each other, the fourth electrode of the capacitor and the gate electrode are not connected to each other.

EFFECT: invention makes it possible to create a thin-film transistor, occurrence of a defect in which may be prevented even in case of leakage in a capacitor connected to a transistor body.

37 cl, 13 dwg

FIELD: electricity.

SUBSTANCE: method of manufacturing of an enhancement/depletion (E/D) inverter having a number of thin-film transistors on the same substrate with channel layers consisting of an oxide semiconductor containing at least one element selected from In, Ga and Zn, involves the stages to form a first transistor and a second transistor; a channel layer thickness of the first and second transistors is mutually different; at least one of the channel layers of the first and second transistors are thermally treated.

EFFECT: expansion of the facilities allowing to manufacturer an inverter with oxide semiconductor thin-film transistors of various threshold voltages, simplified method of manufacturing of the inverter with such characteristics, cost reduction.

13 cl, 18 dwg

FIELD: physics.

SUBSTANCE: in a memory element which comprises a substrate with deposited thin layers of ceric and silicon oxide and metal electrodes for recording and deleting information is made from glass which is pre-cleaned with acetone and isopropyl alcohol, on which a ceric oxide layer is deposited at temperature higher than 600°C and thickness of more than 3 nm and a silicon film with thickness of 50-100 nm.

EFFECT: invention prolongs information storage period, simplifies the manufacturing technology and reduces production expenses.

4 cl, 4 dwg

FIELD: electricity.

SUBSTANCE: amorphous oxide the composition of which changes in direction of the thickness of layer contains the compound the composition of crystal state of which is presented with formula In2-XM3XO3(Zn1-YM2YO)m , where M2 - element of group II with atomic number which is less than that of Zn (for example Mg or Ca), M3 - element of group III with atomic number which is less than that of In (for example B, Al, Ga or Y), x is within the range of 0 to 2, y is within the range of 0 to 1 and m is 0 or natural number which his less than 6, and at that, amorphous oxide has concentration of electron carriers of not less than 1012/cm3 and less than 1018/cm3 and has electron mobility which increases with increase of concentration of electron carriers.

EFFECT: amorphous oxide operates as semi-conductor to be used in active layer of transistor.

7 cl, 10 dwg

FIELD: physics.

SUBSTANCE: in a field-effect transistor which includes an oxide film as a semiconductor layer, the oxide film has a channel part, a source part and a drain part, and concentration of one of hydrogen or deuterium in the source part and in the drain part exceeds that in the channel part.

EFFECT: invention enables to establish connection between the conducting channel of a transistor and each of sources and drain electrodes, thereby reducing change in parameters of the transistor.

9 cl, 13 dwg, 6 ex

FIELD: chemistry.

SUBSTANCE: amorphous oxide compound having a composition which, when said compound is in crystalline state, has formula In2-xM3xO3(Zn1-YM2YO)m, where M2 is Mg or Ca, M3 is B, Al, Ga or Y, 0 ≤ X ≤ 2, 0 ≤ Y ≤ 1, and m equals 0 or is a positive integer less than 6, or a mixture of such compounds, where the said amorphous oxide compound also contains one type of element or several elements selected from a group consisting of Li, Na, Mn, Ni, Pd, Cu, Cd, C, N, P, Ti, Zr, V, Ru, Ge, Sn and F, and the said amorphous oxide compound has concentration of electronic carriers between 1015/cm3 and 1018/cm3.

EFFECT: amorphous oxide which functions as a semiconductor for use in the active layer of a thin-film transistor.

6 cl, 8 dwg

Field transistor // 2390072

FIELD: electricity.

SUBSTANCE: in field transistor, comprising active layer and gate-insulating film, active layer comprises a layer of oxide, comprising In, Zn and Ga, amorphous area and crystalline area. At the same time crystalline area is separated from the first surface of interface, which is surface of interface between a layer of oxide and gate-insulating film, distance of 1/2 of active layer thickness or less, and it within the limits of 300 nm from surface of interface between active layer and gate-insulating film or is in point condition in contact with this surface of interface.

EFFECT: production of field transistor with high drift mobility.

4 cl, 4 dwg, 2 ex

FIELD: electrical engineering.

SUBSTANCE: proposed invention relates to field transistor with oxide semiconductor material including In and Zn. Atomic composition ratio expressed as In/(In+Zn) makes at least 35 atomic percent and not over 55 atomic percent. With Ga introduced into material, aforesaid atomic composition ratio expressed as Ga/(In+Zn+Ga) makes 30 atomic percents or smaller.

EFFECT: improved S-characteristic and drift mobility.

9 cl, 25 dwg

FIELD: electricity.

SUBSTANCE: device contains a body 1 with a cover 2, a container 3 with source melts reservoirs equipped with pistons 4, a multi-sectional holder 14 of substrates, a growth station 5 and channels for melts delivery and output. The container 3 with reservoirs is located under the multi-sectional holder 14 of substrates. The cover 2 is equipped with protrusions to output excess of melts. The device contains additional reservoirs 7 for a part of used melts which are installed over the container 3; each reservoir is equipped with a cover 8 with load and a port for melt discharge to the main container 3 located beneath.

EFFECT: suppressing undesired interaction of impurities in different melts for growing through gaseous phase thus improving technical or electric and physical parameters of the obtained structures.

2 cl, 2 dwg, 2 ex

FIELD: electricity.

SUBSTANCE: invention relates to field transistor having various threshold voltages due to modification of the dielectric multilayer gate structure. Semiconductor structure contains the first field transistor having first multilayer gate structure that includes first dielectric of gate having high dielectric constant exceeding 4.0, section of metal gate, at least one metal section and first conducting section of gate material, and second field transistor having the second multilayer gate structure that contains the second dielectric of gate with high dielectric constant exceeding 4.0, at least one dielectric metal-oxide section and second conducting section of gate material; at that the first field transistor and the second field transistor have different threshold voltages.

EFFECT: invention ensures optimal work characteristics of devices at optimal level of power consumption.

12 cl, 12 dwg

FIELD: electricity.

SUBSTANCE: in the manufacturing method of high-power SHF LDMOS transistors polysilicon applied to gate dielectric is coated with high-melting metal, by high-temperature annealing polycide of high-melting metal is formed at polysilicon surface, by photolithography from polycide of high-melting metal and polysilicon layer below it polycide gate teeth of elementary cells are formed with contact pads joining them from the source side and used as a blocking mask at introduction of boron, phosphorus and arsenic ions to the substrate while forming p-wells, multistage lightly doped n-areas of the drain and highly doped n+-areas of the drain and source of elementary cells, and accurate shunting of polycide gate cell teeth by metal bars is made through polycide branched contact pads joining gate teeth, at that in high-ohmic epitaxial p-layer of the substrate under branched contact pads of polysilicon gate teeth auxiliary local highly doped n+-areas are shaped with a higher doping degree in comparison with p-wells of elementary cells.

EFFECT: invention provides development of modern basic nanotechnology for manufacturing of high-power SHF LDMOS transistors at more accessible and less expensive process equipment.

7 dwg

FIELD: electricity.

SUBSTANCE: in the manufacturing method for a semiconductor device at semiconductor substrate of the first type of conductivity gate dielectric, gate electrode and interlayer isolation over the gate electrode are made, then in windows of the gate electrode by ion-implantation method and thermal diffusion method channel area and source area are made with the second and first type of conductivity respectively, contacts of the metal source are opened with source and channel diffusion areas located in the middle of the gate electrode windows in the layer of silicone at the depth exceeding depth of the source areas, and contacts of the metal gate electrode are opened through interlayer dielectric to polysilicon gate electrode using the single photoresist mask in the single plasmachemical process of silicone oxide and silicone etching by selection of etching rate for oxide over the gate and etching rate for silicone. The ration of vertical etching rate of silicone oxide to horizontal etching rate is not less than 3.

EFFECT: improving the degree of integration due to reduction lateral oxide overetching in contacts.

2 cl, 1 dwg

FIELD: electricity.

SUBSTANCE: method of thin film transistor manufacturing involves heavy-doped monocrystalline silicon plates of n+ conductivity type as a substrate, silicon dioxide layer of 110 nm thickness grown by thermal oxidation in dry oxygen as gate isolator, further forming of amorphous silicon film of 430 nm thickness in HF glow discharge in silane at substrate temperature of 250°C and implanting fluorine ions with 25 keV energy and 1014-5·1015 cm-2 dose rate. After implanting, samples are annealed in nitrogen medium at 200-220°C for 60 minutes, passivating silicon oxide layer of 150 nm is applied in SiH4 and N2O plasma mix, and phosphorus ions with 30 keV energy and 1016 cm-2 dose rate are implanted to form thin amorphous silicon layer of n+ type.

EFFECT: reduced flaw density, improved fabricability, instrument parameters and quality, increased percentage yield of serviceable devices.

1 tbl

FIELD: electricity.

SUBSTANCE: in a manufacturing method of a semiconductor device the gating electrode is formed by in-series application on top of the gate oxide layer of a multi-layer structure consisting of a polysilicone layer, a silicium nitride layer through which electrons may tunnel, a molybdenum layer and the second layer of silicium nitride.

EFFECT: reduced resistance of the gating electrode, provision of manufacturability, improvement of parameters, increase in reliability and percentage yield of serviceable devices.

1 tbl

FIELD: chemistry.

SUBSTANCE: method of making a thin-film transistor involves depositing a layer of undoped n-type α-Si with thickness of 300 nm and a layer of phosphorus-doped n+-type microcrystalline silicon with thickness of 20 nm on a substrate of monocrystalline silicon with a thermally grown layer of silicon oxide successively by gas-phase plasma-chemical deposition at substrate temperature of 300°C; thermally forming, between the drain and gate, a layer of silicon oxide with thickness of 200 nm, which is depressed into a layer of amorphous silicon, followed by deposition of a 500 nm layer of SiO2 by chemical vapour deposition at 250°C and firing the samples in a hydrogen atmosphere at 350°C for 30 minutes.

EFFECT: low stray current, providing processability, improved parameters, high reliability and higher output of nondefective articles.

1 tbl

FIELD: physics.

SUBSTANCE: invention relates to semiconductor electronic engineering. The method of making a transistor microwave LDMOS structure deposited on a gate insulator involves coating polysilicon with a refractory metal; forming a polycide of the refractory metal; depositing a protective photoresist layer on the front side of the substrate; opening windows in the protective photoresist layer, the refractory metal polycide, polysilicon and the gate insulator over source p+-jumpers and adjacent portions of a high-ohmic p--layer of the substrate, thereby initially forming only source lateral faces of polycide gate electrodes of the transistor cells; embedding boron ions into the substrate through the opened windows; removing the photoresist from the front surface of the substrate and, via subsequent diffusion distillation of the impurities embedded into the substrate, forming p-pockets of elementary cells; removing the refractory metal polycide and the polysilicon from the front surface of the substrate in the space between the p-pockets of the transistor cells and forming drain lateral faces of polycide gate cogs and polycide gate electrodes of the elementary cells overall; in the high-ohmic epitaxial p--layer of the substrate at the source and in the space between the drain lateral faces of polycide gate electrodes, forming highly doped source n+-regions and highly doped and multi-stage weakly doped n-regions of the drain of the elementary cells; forming metal shielding electrodes of the transistor cells in the interlayer dielectric; pin-point shutting the polycide gate cogs of the cells with common metal gate buses formed on the top surface of the multilevel interlayer dielectric over source p+-jumpers of elementary cells.

EFFECT: basic process of making powerful silicon microwave LDMOS structures and transistors using cheaper equipment capable of operating in the frequency range of 3,0-3,6 GHz at high drain supply voltages.

5 dwg

FIELD: electricity.

SUBSTANCE: to manufacture a power semiconductor device on the first main side of a substrate (1) of the first type of conductivity they form the first oxide layer (22). Then on the first main side on top of the first oxide layer (22) they form a structured layer (3, 3') of the gate electrode, comprising at least one hole (31). The first alloying admixture of the first type of conductivity is implanted into the substrate (1) at the first main side, using as a mask the structured layer (3, 3') of the gate electrode, and they provide for diffusing of the first alloying admixture into the substrate (1). Then the second alloying admixture of the second type of conductivity is implanted into the substrate (1) at the first main side, and they provide for diffusing of the second alloying admixture into the substrate (1). After diffusion of the first alloying admixture into the substrate (1), but before diffusion of the second alloying admixture into the substrate (1), the first oxide layer (22) is partially removed, and they use a structured layer (3, 3') of the gate electrode as a mask for implantation of the second alloying admixture.

EFFECT: invention provides for development of the method to manufacture a power semiconductor device with low losses of energy in connection condition and with large area of stable operation, besides, which is easier for realisation compared to available methods.

13 cl, 10 dwg

FIELD: electricity.

SUBSTANCE: semiconductor device comprises a thin-film transistor comprising a gate bus, the first insulating film, an oxide-semiconductor layer in the form of an island, the second insulating film, a source bus, a drain electrode and a passivating film, and also a contact site, comprising the first connection element, made of the same conducting film as the gate bus, the second connecting element made from the same conducting film as the source bus and the drain electrode, and the third connection element formed on the second connection element. The second connection element contacts with the first connection element in the first window provided in the first and second insulating films, the third connection element contacts with the second connection element in the second window provided in the passivating film, and the second connection element covers the end surfaces of the first insulating film and the second insulating film in the first window, but does not cover the end surface of the passivating film in the second window. As a result the conical shape of the contact hole of the contact site may be controlled with high accuracy.

EFFECT: reduced damage of a mask.

17 cl, 14 dwg

FIELD: electricity.

SUBSTANCE: in method of SHF LDMOS transistors manufacturing, including manufacturing of feed-through diffusive source p+-junctions of elementary transistor cells in high-ohmic epitaxial p--layer of the source p-p+-silicone substrate, growing of gate dielectric and formation of polysilicone electrodes for gate of elementary cells at the surface of high-ohmic p--layer of the substrate, creation of p-wells for elementary cells in high-ohmic p--layer of the substrate by means of boron ion introduction into the substrate using polysilicone electrodes for the gate and photoresist coatings as a mask and subsequent diffusive redistribution of the introduced additive; when p-wells are made gate dielectric between polysilicone electrodes for the gate of elementary cells is reduced to thickness of 100-300 Ǻ, to the substrate face the first protective photoresist coating is applied, two gaps in the first protective photoresist coating are opened simultaneously respectively at the place of heavy-alloyed n+-regions of drain and source of the elementary cells and phosphorus ions are introduced through them with dose of 0.2-0.6 mcC/cm and energy of 80-140 keV and arsenic ions with dose of 400-500 mcC/cm and energy of 40-80 keV; then the second drain gap is opened and phosphorus ions are introduced through it in the same dose and energy as to the first drain; then the third drain gap is opened and phosphorus ions are introduced through it with less dose and energy in comparison with the second drain; then next grades of lightly-alloyed n--drain regions of elementary cells are formed in similar way. Phosphorus ions are implanted to the next grade with a less dose and energy in comparison with the previous one; thereafter remainders of protective photoresist layer are removed from the substrate face and simultaneous up-diffusion of the introduced additives of phosphorus and arsenic is made.

EFFECT: creating method for manufacturing of powerful silicone SHF LDMOS transistors with reduced transistor cell spacing, improved frequency and energy parameters and higher percent of fit structures output.

7 dwg, 1 tbl

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