Conductive pastes

FIELD: chemistry.

SUBSTANCE: invention relates to conductive pastes for forming metal contacts on the surface of substrates for photovoltaic cells. The conductive paste is substantially free of frit glass. According to one version of the invention, the conductive paste contains organometallic components which form a solid metal oxide phase upon firing and conductive material. The organometallic components are selected from a group which includes metal carboxylates or metal alkoxides, where the metal is boron, aluminium, silicon, bismuth, zinc or vanadium. According to another version, the conductive paste includes multiple precursors which form conductive elements upon firing or heating. The paste is adapted for adhesion to the surface of a substrate and upon firing, forms a solid oxide phase while forming an electrical conductor from conductive materials on the substrate.

EFFECT: use of said conductive paste in a line of a conductive array of photovoltaic cells provides high efficiency and fill factor of the photovoltaic cell.

14 cl, 2 tbl, 2 ex

 

The technical field of the invention

Embodiments of the present invention relate to a conductive pastes, which essentially does not contain glass Frit, and the photovoltaic elements having a line conductive mesh formed of conductive pastes, which essentially does not contain a glass Frit.

Prior art inventions

Conductive paste or mass used for the formation of metal contacts, such as silver grid lines and bus, on the surface of substrates, such as silicon. Such substrates can be used in solar cells or photovoltaic cells, which convert solar energy into electrical energy when the solar photons of light excite electrons from the valence band of the semiconductor in a conductive area of the semiconductor. The electrons that move in a conductive area of a semiconductor, are collected in the metal contacts. Crystalline silicon solar cells in modern industry usually cover the antireflection coating to improve light absorption, which increases the efficiency of the elements. However, the ar coating also acts as an insulator, preventing the transfer of electrons from the substrate to the metal contacts. Ar coatings often contain silicon nitride, titanium oxide or oxydrene.

Conductive pastes typically contain a glass Frit, metal particles or conductive material and organic environment. Particles of metal, usually silver particles, impart conductive properties and act as economatica after formation of metal contacts. For the formation of metal contacts the conductive paste is applied on the substrate by a printing method. The substrate is then calcined at a temperature in the range from about 650°C to about 950°C. In most cases, the required sintering additive, since the applied firing temperature lower than the eutectic point of silver and silicon, and the melting point of silver. In addition, a conductive paste should penetrate through the ar coating for the formation of metal contacts having ohmic contact with the substrate.

Traditional conductive paste containing glass Frit to facilitate the sintering of the metal particles with the substrate and to improve the adhesion and ohmic contact is formed between the metal contact and the substrate. Depending on the composition of the glass Frits can be liquefied when firing at a temperature of from about 300°C to about 600°C. At a dilution glass Frit acquires a tendency to flow in the direction of the edge between particles of metal or particles of silver and anti-reflective coating located on the sub is a waste. Molten glass dissolves substances antireflection coating, and the silver part and the substrate. When the temperature of the molten silver and molten or dissolved substrate to crystallize from the liquid phase. As a result, some of the crystallites of silver capable of penetrating through the antireflection layer and to form an ohmic contact with the substrate. This method is called "fire-through", it facilitates the formation of low contact resistance and more durable connection between the silver and the substrate.

As will be described herein later, the glass Frits are not considered ideal materials for use in "fire-through" method, and therefore there is a need for replacement materials. The use of ORGANOMETALLIC compounds in conductive pastes which do not contain glass Frit described in article Silver Thick Film Metallization for Photovoltaics Fired at 300°C, CJ. Sabo and others (herein called "article clogs"). In article clogs specifically described using silver ORGANOMETALLIC component, such as neodecanoic silver in the conductive mass or paste, which is applied on the silicon wafer by screen printing to form the grid lines. In the abstract to the article Szabo indicated that the printed paste was applied onto silicon wafers or solar cells, dried in t is within 30 minutes at 65°C and annealed at a maximum temperature of 300°C for 70 minutes.

Thus, there is still a need for other substituents glass Frits for use in conductive pastes that promote sintering, reduce the resistivity of photovoltaic elements, and can also improve adhesion and ohmic contact through the antireflection coating.

Short description

In one aspect the present invention provides a conductive paste using a stain that provides the same properties as the glass Frit during firing. In particular, one or more embodiments of the present invention relates to a conductive paste which contains several ORGANOMETALLIC components and conductive materials, where the ORGANOMETALLIC components form a solid metal oxide phase during firing or heating. In at least one embodiment, a conductive paste on the merits does not contain a Frit. When used in the text of this application, the term "essentially does not contain a Frit" means the content of glass Frit in an amount of less than about 1 wt.%. Also, when used in the text of this application, the terms "mass" and "pasta" are used interchangeably.

Although the present invention is not linked to any theory, it is believed that the glass Frits are not the ideal material DL the "fire-through" method, since glass is not a conductor. In particular, the glass tends to surround the crystallites of silver on the border of the metal contact and the substrate. Moreover, the glass forms an insulating phase and prevents the flow of electrons. Applying a conductive paste containing a glass Frit, using methods of inkjet printing can also be problematic, as large particles of Frits can clog or block parts of the mechanism.

One or more options for the implementation of the present invention, a conductive paste may essentially not contain a Frit, and does not require the use of conductive materials, instead of using a variety of precursors, where one or more data predecessors during firing to form a solid metal oxide phase and one or more conductive metal elements.

In one embodiment of the present invention the conductive paste adapted for bonding with the surface of the substrate when applied to the substrate in the absence of Frits. In another embodiment, a conductive paste adapted for decomposition, the firing of ORGANOMETALLIC components and any other organic environment for the formation of a solid metal oxide phase and for the formation of the conductive material of the electrical conductor on the substrate. On the other the mu variant implementation of the invention, the firing or heating the conductive paste, containing several predecessors, adapted to decompose the precursors and any organic medium, forms a solid oxide phase and causes the formation of an electrical conductor on the substrate from one or more of the generated conductive metal elements.

When the conductive paste, one or more variants of execution of the invention is applied on the antireflection coating on a substrate, a conductive paste capable of penetrating through the antireflection coating, forming ohmic contact with the substrate.

In another embodiment, a conductive paste contains a conductive material such as silver powder. In another embodiment, the conductive material used in the conductive paste capable of specalist at temperatures above about 500°C.

In one or more embodiments, the execution of the invention ORGANOMETALLIC components are present in the conductive pastes in the amount of less than about 40 wt.%. In another embodiment, multiple precursors are present in the conductive pastes in the amount of less than about 90 wt.%. ORGANOMETALLIC components and/or precursors of one or more variants of execution of the invention contain one or more metal elements selected from Group IIIA, Group IVA, Group VA, titanium, vanadium or zinc is. In more particular embodiments, the execution of the invention using ORGANOMETALLIC components and/or precursors that include metal elements selected from boron, aluminum, silicon, bismuth, zinc, vanadium or titanium.

According to another variant of implementation of the present invention, a conductive paste may also include one or more phosphorus-containing compounds, modifiers, including metal oxide and/or colloidal suspension of metal.

Another aspect of the present invention relates to a photovoltaic element comprising a semiconductor substrate, the antireflection coating and line conductive mesh formed from a conductive paste, which essentially does not contain a Frit. In one embodiment, a conductive paste contains organic environment conductive material and several ORGANOMETALLIC components. In another embodiment, the conductive paste contains one or more precursors that can form one or more conductive metal elements during firing. In addition, a conductive paste is used in one embodiment, the photovoltaic element was annealed to form grid lines with metal oxide phase and a conductive material, and treated to remove the organic medium and sintering of a conductive material. Conducting m is a material predetermined, used in another embodiment, the invention is a powder of silver and/or capable of specalist at temperatures above about 500°C. In another embodiment, a conductive paste is applied on the antireflection coating and capable of penetrating through the antireflection coating, forming ohmic contact with the substrate. Ar coating, which is deposited a conductive paste, one or more versions of the invention shows a high specific resistance, which prevents the transfer of charge carriers in the chain.

Above quite extensively outlined some of the features and technical advantages of the present invention. Specialists in the art will understand that the described private embodiments of the invention can easily be used as a basis for modifying or designing other structures or ways within the scope of the present invention. Specialists in the art will understand that such equivalent constructions do not go beyond the nature and scope of the present invention described in the accompanying claims.

Detailed description of the invention

Before the description of some illustrative embodiments of the present invention should be understood that the present invention is not limited to the highlighted parts of the construction or stages of the ways described later in this text.

Other embodiments of the present invention that can be implemented or performed in different ways.

Aspects of the present invention include conductive materials and/or precursors for formation of a conductive paste, in substance not containing Frits, which will be described hereinafter in more detail. Predecessors can be an inorganic precursor, such as a metal salt (e.g. silver nitrate) or ORGANOMETALLIC component that forms a conductive metal element during firing.

Predecessors

In some versions of the invention does not require the use of a conductive material, are used instead precursors, which upon firing to form one or more conductive metal elements. When used in the present text, the term "conductive metal elements include copper, silver, gold, platinum and/or other noble metals, and combinations thereof. In one or more versions of the present invention is used and the conductive material, and the predecessors, which form a conductive metal elements.

The use of precursors, which upon firing to form a conductive metal elements, may be useful for the floor of the treatment pastes without metal particles for use in a thin film. Although the present invention is not linked to any theory, it is believed that pasta, not containing particles, or pastes which do not contain conductive material, prevent agglomeration, which may occur when applying conductive pastes way direct printing, such as spraying or inkjet printing.

ORGANOMETALLIC components

One or more embodiments of the present invention include conductive paste containing more than one ORGANOMETALLIC precursor. In General, ORGANOMETALLIC compounds are compounds that contain atoms of metals, including carboxylates of metals such as neodecanoate, acetates and propionate, alkoxides of metals and metal complexes, which are sparingly soluble or insoluble in water. ORGANOMETALLIC components can also contain any aromatic or aliphatic group, and they are sometimes called resinate metals, when the organic part consists of groups derived from polymers or other natural products. Other suitable ORGANOMETALLIC precursors include mercaptide metals. ORGANOMETALLIC components used in one or more embodiments can contain more than one metal atom.

Examples of ORGANOMETALLIC components used with od is Oh or more conductive pastes, include a combination of boron-metal, aluminum-metal, silicon metal, bismuth metal, zinc-and ORGANOMETALLIC vanadium-ORGANOMETALLIC components. Sometimes ORGANOMETALLIC and organo-metallic compound is defined as two categories. When used in the text of this application, the term "ORGANOMETALLIC compound" includes both ORGANOMETALLIC and organo-metallic compounds.

Without being bound to any theory, believe that the firing of ORGANOMETALLIC components are decomposed and the organic part is removed from the conductive paste. Also may be formed of a mixture of metals or metal alloys or metal oxides. The amount of solids obtained after firing, called "the content of solids in ORGANOMETALLIC components in mass%". One or more variants of execution of the invention ORGANOMETALLIC components must be present in the paste in an amount sufficient to form a solids content of at least 0.5 wt.%. Other embodiments of the contain ORGANOMETALLIC components, having a solids content of at least 2-3 wt.%. Without being bound to any theory believe that is analogous to the use of glass Frits in providesi the pastes, the amount of solid substance, derived from the ORGANOMETALLIC component, affects the ability of the conductive paste to form an electrical conductor on the substrate or to form ohmic contact with the substrate. This ability, therefore, improves the performance of the device, comprising a conductive paste, such as a semiconductor, photovoltaic element or auto glass. As indicated in the present text, in one or more versions of the present invention uses more than one ORGANOMETALLIC component. Without the binding of the present invention to any theory believe that the use of more than one ORGANOMETALLIC compound in the conductive paste reduces the resistivity to a greater extent than the use of only one ORGANOMETALLIC component.

In one or more embodiments, the execution of the invention ORGANOMETALLIC components include a bismuth ORGANOMETALLIC compound, silicon ORGANOMETALLIC compound and the boron ORGANOMETALLIC compound. Other variants of execution may include at least one metal component selected from bismuth ORGANOMETALLIC compounds, silicon-ORGANOMETALLIC compounds and/or boron-ORGANOMETALLIC compounds. Other options for the implementation of the program may include one or a combination of bismuth ORGANOMETALLIC compounds, silicon ORGANOMETALLIC compounds, boron-ORGANOMETALLIC compounds, aluminum-ORGANOMETALLIC compounds, zinc-ORGANOMETALLIC compounds and/or vanadium-ORGANOMETALLIC compounds.

One or more variants of carrying out the invention to achieve the desired properties of a single element, or a metal oxide, or colloidal suspensions of metals can be added to the ORGANOMETALLIC components as modifiers to improve the content of any item or add new properties. For example, you can add phosphorus, P2O5 or another type of phosphorus-containing compounds for the production of samoreguliruemykh (self-doping) pastes for use in solar cells.

In addition, ORGANOMETALLIC components on the basis of non-ferrous metals can improve the binding of the film at low temperatures. For example, powders of silver, nano-suspensions of silver and ORGANOMETALLIC components on the basis of non-ferrous metals provide good conductivity and adhesion to ceramic or conformal substrates. Conformal substrates may include, but is not limited to, soft substrates, such as Mylar®, Kapton®, Kaladex® and Melinex®.

Known in the art methods can be used to create a variety of ready-made forms ORGANOMETALLIC components used in the wire is the same pastes according to the options the implementation of the present invention.

To control the final properties can be taken into account additional factors in the development of ORGANOMETALLIC composition components. One principle involves the control of aggressiveness conductive paste on the antireflection coating and preventing contamination of the substrate. Another principle involves the selection of the temperature of thermal decomposition in the range from about 200°C to about 500°C or in a different range depending on the profile of the temperature distribution during firing to provide enough time and heat for the interaction of a solid mixture formed by the decomposition of ORGANOMETALLIC components with conductive material and anti-reflective coating. You may consider using carboxylates of metals or precursors of low-temperature chemical vapor deposition ("CVD") for regulating the temperature of decomposition. The third principle involves the selection of ORGANOMETALLIC components, which have a consistency suitable for printing, or which can also be used as rheology modifiers.

Conductive materials

In one or more embodiment of the invention, in the conductive paste is used conductive material such as silver powder or dispersion form. Other non-limiting examples of suitable conductive mother of the crystals include conductive metals, as gold, copper and platinum in powder or dispersion form.

Conductive material used in one or more embodiments sobritineji, can be in the form of one or more finely ground powders of silver or silver alloys. One or more variants of the run-conductive material must be able to sintering at a temperature above about 500°C.

Other components

A conductive paste on one or more execution options may also include organic media. Organic media disperses dispersed components and facilitates the transfer of the composition of the paste on the surface. In at least one embodiment, the organic carrier includes any suitable inert solvent, polymers and commonly used surfactants. Specifically, the organic carrier dissolves the polymer and disperses the conductive material and ORGANOMETALLIC components before the formation of the conductive paste with a suitable rheology. Various organic carriers, thickeners, stabilizers and/or other conventional additives, or they can be used in obtaining embodiments of the present invention. Examples of solvents include alcohols (including glycols), and esters of such alcohols, terpenes such as pine oil, Turpin is l and others. More specific examples of solvents include dibutyl phthalate, monobutyl ether of diethylene glycol, terpineol, isopropanol, tridecanol and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate. In some embodiments, execution of media are used, which contain volatile liquids to promote faster drying after application to the substrate.

Examples of suitable polymers include ethylcellulose, methylcellulose, nitrocellulose, carboxymethyl cellulose and other cellulose derivatives. Other examples include polymers such as esters of acrylic acid, esters of methacry-ash acid, polyvinyl alcohols, polyvinylbutyral and polyketone.

In a particular embodiment, use solutions of polymers such as polymethacrylates of lower alcohols, while in a more private embodiment, the carrier liquid includes ethylcellulose dissolved in solvents such as pine oil and monobutyl ether of diethylene glycol.

The ratio of organic medium and solid particles in the conductive paste, one or more variants of execution of the invention may vary considerably and is determined by the rheology of the final desired composition, which, in turn, is determined by the requirements of the system to screen printing. In one or more embodiments, the implementation of the Oia conductive paste may contain from about 50 to about 95 wt.% solids and from about 5 to about 50 wt.% organic media.

One or more embodiments of the conductive paste may further contain other additives known in the art, such as dyes and pigments, rheology modifiers, a means of improving adhesion, sintering inhibitors, modifiers doobidoo strength, surfactants, and so forth.

A conductive paste, one or more options you can get with the aid of suitable equipment, such as three-roll mill. Conductive material, ORGANOMETALLIC components, precursors, organic carriers, and any other additives can be pre-thoroughly mix, then dispersive in a three-roll mill.

Photovoltaic cells

In another aspect of the present invention described FG elements containing semiconductor substrate, the antireflection coating on the substrate and the conductive line of the grid. One or more execution options line conductive mesh formed from a conductive paste, in substance not containing Frit. One or more described in this text embodiments, conductive pastes can be used to form conductive lines of the grid. One or more variants of execution of the invention preferably use more than one metallogr-organic component, so that providedata could penetrate through the ar coating on the substrate or to dissolve it, and to establish ohmic contact.

In one or more embodiment of the invention, the semiconductor substrate may be a silicon. You can use other suitable substrate known in the art, such as doped semiconductor substrates. One or more execution options antireflection coating may contain titanium oxide, silicon nitride or other coatings known in the art.

The semiconductor substrate may include monocrystalline or polycrystalline silicon. Antireflection coatings can be applied to the substrate using methods of chemical deposition from the vapor phase. In some versions of the invention for applying the antireflection coating on the substrate using plasma enhanced methods of chemical deposition from the vapor phase. Semiconductor substrates, one or more variants of execution can also be treated or textured to reduce reflection of sunlight and increasing the degree of absorption. One or more variants of execution of the invention the surface of the substrate or on the antireflection coating is applied conductive paste by screen printing or other methods. In one embodiment, the substrate is heated or calcined what about the temperature from about 650° to 950°C for the formation of the grid lines. As described in this application, burnout allows the glass Frit known conductive paste to melt and penetrate through the ar coating. Conductive material used in conductive pastes according to one variant of execution of the invention forms crystallites on the border of the conductors and the substrate, which improves electrical or ohmic contact between the conductors and the semiconductor substrate. In variants of execution, in which two or more predecessors, the firing of one or more precursors to form one or more conductive elements that accelerate the formation of electrical conductors on the substrate.

Without limiting this invention in any way, the following examples more fully described embodiments of the invention.

EXAMPLES

Tested two pasta or mass (Pasta and Pasta), where both toothpastes include powders of silver, several ORGANOMETALLIC components, polymers and solvents. The amount of ORGANOMETALLIC components in the Paste And was 2 wt.% solids, and the amount of ORGANOMETALLIC components in the Paste was 3 wt.% the solids. These pastes were applied by the method of printing and forming front contacts on two solar cells from crystalline silicon. Measured performance to the each photocell, the values were normalized relative to the Pasta And; values are presented in Table 1.

Table 1
The effect of the content of solids generated by metal-organic components of the paste.
PastaThe solids contentVoc(V)(Jsc) (mA/cm2)The fill factorEfficiency (%)
A2%1.001.001.001.00
B3%0.991.031.751.78

"Fill factor" and "efficiency" are the units of performance of the semiconductor. The term "fill factor" is defined as the ratio of the maximum power (Vmp×Jmp), divided by the product of the current density at short circuit (Jsc) and open circuit voltage (Vocin the current-voltage (I-V) characteristics of solar cells. The open circuit voltage (Voc) is the maximum voltage generated in the idling mode. The density of short circuit current (Jsc) represents the maximum current density without load short circuit. The fill factor (FF), thus, defined as (VmpJmp)/(VocTsc), where Jmpand Vmprepresent the current density and voltage at the maximum power value.

The term "efficiency" represents the percentage of power converted (converted from absorbed sunlight into electrical energy) and collected at the junction of the photocell and the electrical circuit. The efficiency (η) are calculated as peak power (Pm), divided by the product of the total incident radiation (E, measured in W·m-2) and the area of the device (A, measured in m) at standard test conditions, where η=Pm/(E×A).

As shown in Table 1, the Pasta demonstrated a higher fill factor and efficiency than Pasta A. On the basis of these results, consider that a conductive paste provides a higher fill factor and efficiency when it contains ORGANOMETALLIC components generate a higher solids content.

The reference in this about what Isani "one variant of carrying out the invention", some embodiments of the invention, one or more embodiments of the invention or a variant implementation of the invention" means that a particular feature, structure, material, or characteristic described in connection with the option of perform included in at least one embodiment of the present invention. Thus, phrases such as "in one or more embodiments of the invention, in some embodiments of carrying out the invention", "in one embodiment" or "in an embodiment" in various places of this description do not necessarily refer to one and the same variant implementation of the invention. In addition, private signs, patterns, materials or features may be combined in any suitable manner in one or more embodiments, execution.

Although the invention herein has been described with reference to private ways of execution, you need to understand that these options only illustrate the principles and scope of the present invention. Specialists in the art will understand that various modifications and changes of method and hardware design of the present invention without departing from the scope of the essence and scope of the invention. Thus, it is assumed that the present invented the e includes modifications and changes within the appended claims and its equivalents.

1. A conductive paste for application to the semiconductor for use as a photovoltaic element containing many ORGANOMETALLIC components, which form a solid metal oxide phase during firing, and a conductive material, in this case, the paste is essentially free from glass Frits, and this paste is adapted for coupling with a surface of the substrate when applied to the substrate in the absence of Frits and, when burning, decomposition of ORGANOMETALLIC components that forms a solid oxide phase and causes the formation of conductive materials electrical conductor on the substrate, and ORGANOMETALLIC components selected from the group including carboxylates of metals or alkoxides of metals, where the metal is boron, aluminum, silicon, bismuth, zinc or vanadium.

2. A conductive paste for application to the semiconductor for use as a photovoltaic element containing many predecessors, which form a solid metal oxide phase during firing or heating, and one or more of these precursors capable of forming one or more conductive metal elements during firing, with pasta, essentially free from glass Frit is s, and this pasta is adapted for coupling with a surface of the substrate when applied to the substrate and, when burning, decomposition of one or more precursors that forms a solid oxide phase, which causes the formation of one or more conductive metal elements of the electrical conductor on the substrate in the absence of a glass Frit, where the precursor contains metal elements selected from silicon.

3. The paste according to claim 1 or 2, where when applying the paste on the anti-reflective coating on a substrate, this conductive paste capable of penetrating through the antireflection coating with the formation of the ohmic contact with the substrate.

4. The paste according to claim 1, where the conductive material contains a silver powder.

5. The paste according to claim 1 or 2, where conductive material capable of specalist at temperatures above about 500°C.

6. The paste according to claim 1, where the organic components are present in amounts less than about 40 wt.%.

7. The paste according to claim 1, where the ORGANOMETALLIC components further include one or more metals selected from Group IIIA, Group IVA, Group VA or titanium.

8. The paste according to claim 1 or 2, additionally containing fosforsoderzhashchie connection.

9. The paste according to claim 1 or 2, additionally containing modifier, including a metal oxide or colloidal suspension of metal.

10. The paste according to claim 2, where several p is electonical present in amount less than about 90 wt.%.

11. The paste according to claim 2, where several predecessors additionally include one or more metals selected from Group IIIA, Group IVA, Group VA, titanium, vanadium or zinc.

12. Pasta in claim 11, where several predecessors additionally include boron, aluminum, bismuth, titanium, zinc and vanadium.

13. Photovoltaic element containing semiconductor substrate ar coating and line conductive mesh formed from a conductive paste according to any one of claims 1 or 3-9, which includes organic environment, and which is burned to generate grid lines containing metal oxide phase and a conductive material, where the paste was treated to remove the organic medium and sintering of a conductive material.

14. The photovoltaic element according to item 13, in which the antireflection coating is deposited on the surface of the substrate, and a conductive paste is applied on the antireflection coating of the antireflection coating has a high specific resistance, impeding the transfer of charge carriers in the chain.



 

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1 cl, 2 tbl, 9 ex

FIELD: solar-to-electrical energy conversion; contacts for photoelectric semiconductor converters of various configurations.

SUBSTANCE: proposed contact is built on thin silicon semiconductor wafer and has narrow current-carrying conductors in the form of current-collecting strips crossed at right angle by two wider current-carrying conductors in the form of current-collecting strips disposed symmetrically either side of longitudinal axis. Metal coat applied to 95-98% of surface area of narrow current-collecting strips can be disposed at distance of 0 - 3 mm from edges of wide current-collecting strips, that is, in immediate proximity of wide current-collecting strip edges. Invention specification also gives manufacturing process for this thick-film contact of silicon photoelectric converter.

EFFECT: enhanced mechanical strength of joints and contact mechanical design, extended service life of converter and thick-film contact, reduced labor consumption for its manufacture, enhanced photoelectric converter efficiency.

14 cl, 3 dwg

The invention relates to a device made from skodlivych semiconductors for work in the infrared wavelength range

Integrated circuit // 2133067

FIELD: metallurgy.

SUBSTANCE: proposed method comprises alloying lead-free alloy with nickel whereat nickel content approximates to 1-2 ppm and applying alloy on substrate copper bedding. Invention covers also micro-electronic structures.

EFFECT: better strength of solder joints and resistance to electromigration in micro-electronic cases.

29 cl, 5 dwg

FIELD: electrical engineering.

SUBSTANCE: in the chip that includes a group of input contact stubs consisting of variety of input contact stubs located in the line along one long side of its lower surface and a group of output contact stubs consisting of variety of output contact stubs located in staggered ordering along the other long side of the lower surface there is a group of nonworking contact stubs in the area between the group of input contact stubs and the group of output contact stubs. The group of nonworking contact stubs includes variety of rectangular nonworking contact stubs that do not fulfil a function of electrical connection and have a long side along the direction perpendicular to long sides of the lower surface.

EFFECT: reduced distance between contacts; the chip is capable to prevent formation of unreliable connection between the chip and substrate where the chip is installed.

18 cl, 22 dwg

FIELD: production of electronic components.

SUBSTANCE: electronic components are disposed in special clamping device and oriented to butt-end surfaces. Clamping tool inserts have inclined slots to form end masks in the course of further deposition of conductors onto end surfaces of components. "Free" masks are fixed first on face side of components and then on their underside to provide for depositing conductors on face and underside surfaces of components; they have slits aligned with slots provided in clamping tool inserts. Conductors are deposited onto face and partially onto end surfaces , then onto underside surfaces of components, and once more onto their end surfaces by way of vacuum evaporation.

EFFECT: reduced cost and enhanced reliability of group method for depositing conductors onto surfaces of components in production of three-dimensional electronic modules, composite and two-way electronic devices.

6 cl, 4 dwg

The invention relates to a semiconductor microelectronics

The invention relates to the development and production of equipment on the basis of microelectronics and semiconductor devices, and can be widely used in the manufacture of multilayer printed circuit boards, as well as switching structures for multichip modules

The invention relates to the technology of semiconductor Assembly dei priori, and more specifically to a method of attaching a conductive element to the semiconductor Priora, and can be used for mounting integrated circuit (IC) multielement photodetector (AF)

The invention relates to the production of electronic devices, in particular to equipment for attaching the wire leads of the integrated circuits (IC)

FIELD: electricity.

SUBSTANCE: current-conducting silver paste for rear electrode of solar cell includes fine powder of silver 45-50 wt %, frit 3-9 wt %, preferably 3-6 wt %, and organic bonding agent 46-52 wt %. Silver powder has average size of particles D50 equal to 1.5-5.0 mcm, and 38-48 wt % of silver powder may have average size of particles D50 equal to 2.0-5.0 mcm, preferably 2.5-3.0 mcm, and 2-10 wt % of silver powder may have average size of particles D50 equal to 1.5-4.0 mcm, preferably 1.5-1.8 mcm. Organic binding agent as film-forming one contains ethyl cellulose in quantity of 4-10 wt %.

EFFECT: reducing paste consumption during screen-printing; reducing content of precious metals powder in paste, improving rheological and printing properties of paste as well as adhesive properties.

4 cl, 3 dwg, 1 tbl

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