Etching method and etching system

FIELD: physics; electricity.

SUBSTANCE: etching system contains plasma-generating facilities for plasma generating in vacuum chamber, high-frequency displacement voltage source, supplying high-frequency displacement voltage to electrode-substrate, floating electrode opposite to electrode-substrate in vacuum chamber and supported in floating condition by electric potential, solid material placed on the side of the floating electrode directed to electrode-substrate to form film layer protecting from etching, and control unit for periodic supply of high-frequency voltage to floating electrode. Etching method includes repetition, in specified sequence, of substrate etching stage by means of etching gas supplied to vacuum chamber, and film layer formation stage protecting substrate from etching by sputtering of solid material opposite to substrate.

EFFECT: high etching selectivity when using mask as well as production of anisotropic profile and great etching depth.

22 cl, 7 dwg

 

The technical field

This invention relates to a method of etching and to install etch, which may find application in the field of forming micro-Electromechanical systems and fabrication of microelectronic devices.

The level of technology

The fluorine atoms (radicals) react in a spontaneous way with silicon at room temperature, resulting in no possibility of obtaining anisotropic etching profile on a silicon substrate, if the substrate is not cooled to -140°C, when the substrate in the vertical direction is formed deep hole on the side wall located perpendicularly relative to the surface of the substrate, while suppressing the enlargement of the hole in the transverse direction. Therefore, when the etching of silicon with the use of fluorine gas is necessary to prevent isotropic etching through the formation protects against etching or the protective film on the side wall with the aim of obtaining the desired anisotropic etching profile in silicon.

Known methods of anisotropic etching with the formation protects against etching film on the side wall for receiving an anisotropic etching profile in silicon (see patent documents 1 and 2).

In the anisotropic etching method described in patent document 1, turn and C is erevna perform the steps of polymerization and stages of etching with education at every stage of polymerization of the polymer layer on the surface, the "opened" at the immediately preceding stage etching to protect the side surface from etching in a subsequent step of etching.

In the anisotropic etching method described in patent document 2, turn and repetitive way perform the step of anisotropic etching by introducing a gas mixture containing etching gas (SF6and passivating gas (CHF3C4Fnetc), in the process chamber and the excitation of a mixture of electromagnetic radiation and simultaneously applying a high bias voltage to the substrate and the stage of formation of the unsaturated monomers in the plasma by excitation of a specified gas mixture electromagnetic radiation and simultaneously forming a protective polymeric coating on the side wall having an exposed surface exposed to the etching through the application of a low bias voltage to the substrate.

Patent document 1: U.S. patent No. 5501893.

Patent document 2: publication laid patent application of Japan No. 2000-323454.

However, in the known method described in patent document 1, the temporal correlation of each stage of the etching and the next stage of polymerization depends on the speed of the input gas mixture is changed from time to time, causing a negative effect on the uniformity of the management, because during etching and stages of polymerization repetitive use of different gas mixtures. In addition, for the implementation of this method requires a complex device, since the transition from one of the two gas mixtures to the other and back should be used the automatic valve with solenoid actuator. In addition, there is a problem of formation of particles due to the introduction of the gas mixture on the stages of polymerization.

In the known method described in patent document 2, it is necessary to change the attached to the substrate bias voltage from a level suitable for stage etching, to the level appropriate to the stage of polymerization, and back, and, therefore, requires a control system with a complex configuration, which increases the cost of the device for implementing this method. In addition, there is the problem of generation of particles due to the introduction of the gas mixture on the stages of polymerization. In addition to formation of the polymer film must be applied RF-power with great energy, which increases energy costs.

In addition, the method of forming protecting against etching the film using pestiviruses gas only from a few percent to just over 10% entered pestiviruses gas involved in the formation of p is Enki. The passivating gas which does not participate in the process of formation of a film produced from the vacuum chamber. As the passivating gas shows strong warming effect of the atmosphere and is a negative factor from the point of view of environmental protection, dated passivating gas should be collected and recycled. The operation processing pestiviruses gas is expensive, and for this reason the use of pestiviruses gas is undesirable.

To obtain anisotropic etching profile is also known a method of etching with the application of a high bias voltage, in which HBr is used. However, when using this method it is impossible deep etching of silicon due to the problems that it causes, including the fact that it is impossible to expect a high etching selectivity due to the use of the mask, and it is not suitable for forming micro-Electromechanical systems and fabrication of microelectronic devices, although it can be used to generate a more microscopic images.

Disclosure of inventions

Considering the above problems of the prior art, the purpose of this invention is the provision of a method of etching and installation etching, adapted to obtain a high selectivity etching in case the e mask, excellent anisotropic profile and great depth of etching.

In the first aspect of the present invention has been proposed to install etching containing plasmagenericshell means for generating plasma in the vacuum chamber, the electrode substrate located in the vacuum chamber, and a source of high frequency (HF) power bias applying high-frequency power bias on the electrode substrate, and carrying out etching of the substrate mounted on the electrode substrate, characterized in that it also contains:

the floating electrode, the opposite electrode substrate

the high-frequency power source for supplying high frequency power to the floating electrode,

the solid material is located on the facing electrode substrate side of the floating electrode so as to be sprayed from the formation protects against etching film on the substrate, and

a control unit for controlling the high-frequency power supplied to the floating electrode to periodically (intermittently) spraying of solid material.

In the installation of etching according to this invention also provides a means of introducing etching gas, and the control unit may be designed to control the supply of high frequency power to the floating electrode, by applying a high frequency power offset the deposits on the electrode substrate and the introduction of the etching gas in the vacuum chamber in sequence.

The control unit may be designed to function in such a way as to introduce etching gas into the vacuum chamber at the time when the solid material is not sprayed.

The control unit may be designed to function in such a way as to introduce etching gas into the vacuum chamber at the time when the solid material is not sprayed or when the electrode substrate is not supplied high-frequency power offset.

The control unit may be designed to function in such a way as to apply high-frequency power bias on the electrode substrate after sprayed solid material.

In one embodiment, the implementation of the installation etching according to this invention, the high-frequency power source connected to the floating electrode through a switch or Mariconda, as well as with plasmagenericshell tool to be used for generating plasma, and the control unit may be designed to control the switch or Mariconda, depending on what is appropriate, therefore, to apply high frequency power to the floating electrode by spraying of solid material.

The control unit may be designed to control high-frequency power source so that the power output of this IP is student varied during the spraying of solid material during the etching of the substrate.

Solid material for forming protecting against etching of the film can be selected from a fluorine-containing polymer, silicon, carbon, silicon carbide, silicon oxide and silicon nitride. This solid material may be silicon, and thus may be continuously introduced etching gas and the oxide.

The substrate may be a silicon substrate. Also, the substrate may be a quartz substrate.

In accordance with the second aspect of the present invention a method of etching for etching the substrate placed in the vacuum chamber by generating plasma is characterized by the fact that repetitive way perform:

the step of etching the substrate on which the substrate is hounded by introducing etching gas into the vacuum chamber,

the step of forming the protecting against etching film on the substrate to form protects against etching of the film by sputtering the solid material opposite the substrate, and

the removal phase protects against etching film, which serves high-frequency power bias on the electrode substrate, on which is placed the substrate, and etched part of protecting against etching of the film.

As the spray gas phase formation protects against etching of the foil may be used an inert gas.

During etching of the substrate can be used for the feed into the mixture of inert gas and the etching gas.

At the stage of removal protects against etching of the foil may be used an inert gas or mixture of inert gas and the etching gas.

At each step of etching the substrate, the step of forming the protecting against etching film and stage removal protects against etching the film in a vacuum chamber can be introduced certain inert gas, and the etching gas may be added to the inert gas for the formation of the gas mixture used during etching of the substrate or the step of etching the substrate and the step of removing protecting against etching of the film.

The inert gas may be selected from Ar, Xe, Kr and N2.

The etching gas can be selected from SF6, NF3F2, SiF4and XeF2.

In the method of etching according to this invention the step of etching the substrate can be performed without supplying high-frequency power bias on the electrode substrate.

In the method of etching according to this invention the solid material can be selected from a fluorine-containing polymer, silicon, carbon, and silicon carbide.

In the method of etching according to this invention at the stage of formation protects against etching of the film in the case of using silicon as a solid material is continuously introduced etching gas and oxygen.

Advantages of the invention

In the installation of etching according to wannamoisett floating electrode is located opposite to the electrode substrate in a vacuum chamber and is supported in a floating state, the electric potential, and on the side of the floating electrode facing the electrode substrate, a material for forming protecting against etching film, and a control unit to periodically apply high frequency power to the floating electrode. With this design there is no need for valves with solenoid actuator to move from one gas to another. In addition, there may be a reduced number of switching valves and there is no need to provide a high-vacuum pump to remove gas type CF, which is required at the stage of polymerization, however, is a hindrance during etching, so that the unit as a whole can be simplified and reduced in size to reduce its cost. In addition, when compared with the installation, in which at the stage of polymerization is injected gas type CF, when installed in accordance with this invention substantially reduces the degree of formation of particles, which facilitates maintenance of the installation and provides the possibility of stable operation.

In accordance with the method of etching according to the invention, the step of etching the substrate on which the substrate is hounded by introducing etching gas into the vacuum chamber, the step of forming the protecting against etching film on the substrate to form asiausa from etching the film by sputtering the solid material, located opposite the substrate, and the step of removing protection from etching film, which serves high-frequency power bias on the electrode substrate, on which is placed the substrate, and tell part of protecting against etching film, perform repetitive manner, reducing the number of different technological stages and providing opportunities for highly selective etching in the case of using the mask. In this case, it is possible to implement vysokoporodnogo and deep etching. In addition, when compared with the installation, in which at the stage of polymerization is injected gas type CF, when installed in accordance with this invention substantially reduces the formation of particles, which makes it possible to treat the substrate with high output.

Brief description of drawings

Hereinafter the invention will be described in more detail with reference to the accompanying drawings, which illustrate a preferred embodiment of the invention.

Figure 1 is a schematic diagram illustrating an embodiment of the installation etching according to this invention.

Figure 2 is a block diagram illustrating the control unit of the installation of figure 1.

Figure 3 is a graph illustrating the sequence of modulation spray set, such as the er, for the control unit of figure 2 in order to be used in the operation of the embodiments installation etching of figure 1.

Figure 4(a)-4(d) are diagrams explaining the operation of the plant of figure 1.

Figure 5 is a schematic illustration in cross-section, showing the etched product obtained through the installation of figure 1.

6 is a graph illustrating the relationship between the rate of formation of the polymer film and the high-frequency power, filed on high-frequency antenna coil installation 1.

7 is a diagram illustrating the relationship between the rate of formation of the polymer film and gases, which can be used in the installation of figure 1.

The best option of carrying out the invention

Figure 1 shows a schematic diagram of a variant of implementation of the installation etching of silicon, which is installation with the discharge in an inhomogeneous magnetic field with a neutral circuit (NLD). Referring to Figure 1, which illustrates this embodiment of the installation etching, position 1 denotes a vacuum chamber with section 1a of generating plasma in the upper part and section 1b of the processing substrate. Section 1b of the processing substrate is located discharge opening 1c and connected to suitable the overall system output.

Section 1a of generating plasma is supplied cylindrical dielectric side wall 2, and outside of this dielectric side wall 2 there are three electromagnetic coils 3, 4, 5, which function as a means of generating magnetic fields to produce an inhomogeneous magnetic field with a neutral path in the vacuum chamber 1. These coils give an inhomogeneous magnetic field with a neutral outline in section 1a of generation of plasma, located in the upper part of the vacuum chamber 1. In the lower part of the vacuum chamber is placed the electrode substrate 6 through laid between them an insulating element. The electrode substrate 6 is connected to a source 8 of the high-frequency power to be used for the application of RF bias through the blocking condenser 7, and the electrode substrate 6 is fixed to the silicon substrate 9 to be processed by etching.

Between the three electromagnetic coils 3, 4, 5 and the outer side of the dielectric side wall 2 has three high-frequency coil 10 to generate plasma. High-frequency coil 10 is connected to a source 11 of the high-frequency power and are designed for the application of an alternating electric field along the magnetic neutral loop formed within the section 1a of generation of plasma, located at the top frequent the vacuum chamber 1, for the formation of the discharge plasma.

Although for the purpose of this invention it is preferable to use a setup discharge in an inhomogeneous magnetic field with a neutral circuit (NLD), because in such a setting can be adjusted diameter and the size of the region of the plasma, allowing a better control of the etching operation and the operation of spraying compared using the typical installation, the invention is in no way limited to the use of NDL-installation, provided that the applied setting can generate plasma.

The top plate 12 section 1a of generation of plasma, located in the upper part of the vacuum chamber 1, is rigidly attached to the upper end portion of the dielectric side wall 2 by means of an insulating element (not shown) hermetically sealed manner. The top plate 12 is positioned in such a way as to be supported in a floating state, the electric potential, and functions as a floating electrode. The top plate 12 is formed with a hard material 13, which may be arbitrarily selected from a fluorine-containing polymer, silicon, carbon, silicon carbide, silicon oxide and silicon nitride so as to operate as a target. To the floating electrode 12 from source 11 plasmagenericshell the high-frequency power to high-frequency antenna coil 10 is supplied high-frequency power through varikont 14, which is a control unit for intermittent feeding high frequency power to the floating electrode 12, and the control unit is located on the branch from the supply line of the power source 11 plasmagenericshell high-frequency power to high-frequency antenna coil 10 in order to provide generation on the floating electrode 12 avtomashine or samospaseniyu. Varikont 14 may be replaced by a switch. The source 11 of the high-frequency power can be established in two high-frequency power sources, one for floating electrode 12, and the other for high-frequency antenna coil 10.

Section 1a of generation of plasma, located in the upper part of the vacuum chamber 1, provided with a gas supplying section 15 for the introduction of primary or inert gas and the etching gas into the vacuum chamber 1 and the gas supplying section 15 is connected to node 16 mixing of gases. Node 16 mixing gases, in turn, is connected to a source of inert gas (not shown) through line 17 inert gas and etch gas source (not shown) through line 18 to supply the etching gas and the block 19 flow control and flow rate of etching gas. The source of inert gas is arranged to supply at least one inert gas of Ar, Xe, Kr or N2. Source Tr is correct gas is arranged to supply at least one etching gas of SF 6, NF3F2, SiF4or XeF2.

Figure 2 is a block diagram of a control unit used in the installation of figure 1, showing the working nodes to which it is connected. Figure 2 position 21 marked the control unit intended to control the operation of each component of the installation of figure 1. The control block 21 includes a block 22 of arithmetic operations, unit 23 of the memory, clock/timer 24, block 25 of the input unit 26 of the display (the display).

The control block 21 is connected to the block 19 controlling the flow of etching gas, Mariconda 14, a source 11 of the high-frequency power source 8 high-frequency power offset.

Block 22 of arithmetic operations is configured to generate control signals to these components by using the sequence recorded in the memory block 23, and the prescribed values entered into it from the block 25 input and output when accessing the clock/timer 24.

The operator can, through the block 25 set time spraying of solid material 13, while etching of the substrate 9, the time of application of the bias to the electrode substrate 6, the rate at which power is applied to the floating electrode 12 for spraying, the speed with which the power offset is applied to the electrode substrate, and the speed with which you enter etching the gas. Unit 26, the display shows the entered value and controlled state.

Below will be described the operation of the illustrated installation etching with the above configuration with reference to the sequence of modulation of the spray shown as an example in figure 3.

3 shows timing diagrams of the three cycles, each of which includes the step of etching the substrate, the step of forming the protecting against etching of the film and the stage of removal protects against etching of the film. Figure 3 the signal is A trigger signal, In the signal indicating the synchronization control unit 19 flow control and flow rate of etching gas, while the signal From the signal indicating the synchronization control Mariconda 14, and the signal D and signal E are signals indicating, respectively, to synchronize the source control 11 high-frequency power source 18 of high-frequency power offset.

Initially, in cycle 1, unit 19 flow control and flow rate of etching gas is driven to perform the step of etching the substrate, which is designated as t1, for introducing etching gas. Node 16 gas blending mixes the gaseous argon (Ar)coming on line 17 inert gas, etching gas, which is a SFsub> 6and the resulting gas mixture is introduced into the vacuum chamber. Varikont 14 and the source 8 of the high-frequency power offsets are supported in a state of "off", so that high-frequency power is not supplied to the floating electrode 12 and the electrode substrate 6. Power from the source 11 of the high-frequency power is supplied to the antenna coil 10 for generating the plasma, resulting in the substrate 9 is exposed to the etching process.

Then, the operation unit 19 flow control and flow rate of etching gas is suspended to perform the next stage in the formation protects against etching of the film, which is designated as t2, while the supply of the etching gas, i.e. SF6also suspended, so that the vacuum chamber is introduced only gaseous Ar. This enables varikont 14 to increase the power output of the source 11 of the high-frequency power, so that high-frequency power is applied to the upper plate, i.e. on the floating electrode 12. Under these conditions, the target with the inner side of the floating electrode 12 is sprayed, and the silicon substrate 9 is deposited film of fluorine-containing polymer as protecting against etching of the film.

After that, the supply of high frequency power to the floating electrode 12 is suspended, and the high-frequency power is supplied to the electrode substrate 6 to run on the next stage of removal protects against etching film, which is designated as t3. Under these conditions, the surface deposition of a film of fluorine-containing polymer, which is located parallel to the surface of the silicon substrate 9 is removed, although the film of fluorinated polymer on the side walls of the pattern, which is obtained with the deposition on the silicon substrate 9 is not removed and remains in place. At this time, the block 19 flow control and flow rate of etching gas may be included for introducing an etching gas, or it may not be included.

In cycle 2, the operation returns to the step of etching the substrate, and the block 19 flow control and flow rate of etching gas is driven. Node 16 gas blending mixes the gaseous Ar coming on line 17 inert gas, etching gas, which is a SF6and the resulting gas mixture is introduced into the vacuum chamber. Supply RF power to the floating electrode 12 and the electrode substrate 6 is supported on the stage of etching in the off state.

After this stage of the formation protects against etching film, stage removal protects against etching of the film and the step of etching the substrate are repeated to continue etching until then, until you reach the desired depth of etching.

Alternatively, you can organize the functioning of such education is, after deposition of the film of fluorinated polymer on a silicon substrate 9 to the electrode substrate 6 is applied a high frequency offset in order to remove the deposited film of fluorine-containing polymer on a plane parallel to the surface of a silicon substrate 9, leaving a film of fluorinated polymer on the side walls of the pattern, which is formed in the form of deposits, at the same time, the etching gas is mixed with the main gas and injected into the vacuum chamber 1, so that the operation may proceed to step etching.

As another alternative, it is also possible the flow of the gas mixture from the primary gas and the etching gas during all process stages.

Example

Now the invention will be described hereinafter as an example, based on figure 3 presents the sequence modification spray, with reference to Figure 4. On the surface of the substrate 9 was formed mask 30 of SiO2that was partially removed in accordance with the pattern according to which the substrate should be subjected to etching.

First operated unit 19 flow control and flow rate of etching gas phase etching of substrate, labeled (a) in figure 4, and node 16 mixing gases mixed gas Ar coming on line 17 filing in the bound gas with a flow rate of 50 LSM 3/min, and the etching gas, i.e. SF6coming with a flow rate of 50 LSM3/min. This gas mixture was introduced into the vacuum chamber 1, and applying a high frequency power to the floating electrode 12 and the electrode substrate 6 was switched off. Under these conditions, carried out the etching process within 7 seconds. As a result, the substrate 9 vytavlyali to a predetermined depth in those areas where we removed the mask 30.

Then, at the stage of formation protects against etching of the film, labeled (b) in figure 4, the operation unit 19 flow control and flow rate of etching gas is stopped and, therefore, stopped the supply of the etching gas SF6and introduced into the vacuum chamber only gaseous Ar at a flow rate of 50 LSM3/min, and the upper plate, i.e. the floating electrode 12, applied high-frequency power. Under these conditions, the target with the inner side of the floating electrode 12 was sprayed for the deposition of fluorine-containing polymer within 90 seconds on the entire surface of the silicon substrate 9 and the mask 30 for forming protecting against etching of the film 31. This protects against etching film 31 includes film 31-1, 31-3, deposited on flat surfaces parallel to the surface of a silicon substrate 9 and the film 31-2, deposited on each of the vertical side panels of the figure.

After that, at the stage of removal protects against etching of the film, labeled (c) in figure 4, has suspended the supply of high frequency power to the floating electrode 12 and applied high-frequency power of 200 W to the electrode-substrate 6 for 12 seconds. Under these conditions, film 31-1, 31-3 fluorine-containing polymer deposited on flat surfaces parallel to the surface of a silicon substrate 9, was removed, and the film 31-2 fluorine-containing polymer on the side walls of the figure, which was obtained with the deposition on a silicon substrate 9, remained in place.

Then, in the step of etching the substrate, indicated as (d) in figure 4, gaseous Ar coming on line 17 inert gas with a flow rate of 50 LSM3/min, and the etching gas, i.e. SF6coming with a flow rate of 50 LSM3/min, mixed again. This gas mixture was introduced into the vacuum chamber 1 and cut off supplies high frequency power to the floating electrode 12 and the electrode substrate 6. Under these conditions, carried out the etching process within 7 seconds. The result has poisoned the bottom of the holes formed at the previous stage of etching of the substrate, while protecting against etching film 31-2 on vertical surfaces of each of the holes was not removed and remained in place. Respectively provided with the opportunity to achieve aniso ropneho etching in the vertical direction.

Process steps (b)-(d) in Figure 4 was repeated thirty times. Figure 5 presents a schematic representation in cross section obtained etched products.

The following are the preferred processing conditions in the case of the present invention:

phase etching:

Pa/Pb = 2000/0 W

Ar/SF6= 50/500 LSM3/min

the pressure in the vacuum chamber = 50 mtorr

the stage of deposition of the polymer:

Pa/Pb = 1000/0 W

Ar = 50 STS3/min

the pressure in the vacuum chamber = 20 mtorr

the top plate = 200 pF

the stage of removal of the polymer:

Pa/Pb = 2000/25 W

Ar/SF6= 50/500 LSM3/min

the pressure in the vacuum chamber = 50 mtorr

6 is a graph illustrating the relationship between the rate of formation of the polymer film and the high-frequency power, filed on high-frequency antenna coil 10 of the installation of figure 1. Graph 6 on the x-axis is the wave number (cm-1), and on the y - axis the absorbance (in arbitrary units).

7 is a diagram illustrating the relationship between the rate of formation of the polymer film and the gases that can be used in the installation of figure 1. Chart 7 on the x-axis is specified gases, and on the ordinate axis deferred the rate of formation of the polymer film. As can be seen from Fig.7, the speed f is Mirovaya polymer film is reduced by about half with the introduction of the gas mixture of Ar and SF 6compared to the level that is achieved by the introduction of only one gaseous Ar, and falls essentially to zero when the suspension of the supply of the Ar and the introduction of only gaseous SF6. Therefore, a high rate of formation of the polymer film can be achieved when the deposition of the film of fluorinated polymer on the substrate by suspending the supply of etching gas.

Although the material of the inner wall of the upper plate 12 in the described implementation may be used fluorine-containing polymer, silicon, carbon, silicon carbide, silicon oxide or silicon nitride, for the purpose of the present invention as an alternative you can also use connection, or a composite of any of the above substances.

When using silicon as a solid material are the Foundation for continuous introduction of the etching gas and oxygen gas at the stage of formation protects against etching film, on which the solid material is sprayed. As this solid material sprayed silicon, silicon and etching gas/gaseous oxygen react with each other in the gas layer with the formation of silicon compounds (sulfide, oxide, sulfide/oxide and the like). Protects against etching film is formed by deposition of such compounds of silicon apologice 9.

Although the described embodiment refers to the NLD installation etching, it should be understood that the invention could be implemented as well as the installation of etching induction-coupled plasma (IPC).

In the installation of etching according to this invention is not used passivating gas, and, consequently, the intensity of consumption and the intensity of the gas release, which shows strong warming effect of the atmosphere, such as fluorocarbon gas are low. Accordingly, the invention reduces the load on the environment and to exclude the costs of processing the produced gas. In addition, SF6may be replaced by F2.

In addition, in accordance with this invention it is possible to poison not only the silicon substrate, but also quartz (SiO2, borosilicate glass, Pyrex, soda glass). More specifically, quartz (SiO2, borosilicate glass, Pyrex, soda glass) can travisa through a given solid material (CxFx) when applying a high frequency power to the electrode-substrate along with spray CxFx by feeding high frequency power is also on the floating electrode.

Industrial applicability

As the method of etching and installation of etching in accordance with this invention are adapted for Costigan is I high selectivity etching by using a mask and get excellent anisotropic profile and great depth of etching, they can find application mainly in the field of forming micro-Electromechanical systems and fabrication of microelectronic devices.

1. Installation etching containing plasmagenericshell means for generating plasma in the vacuum chamber, the electrode substrate located in the vacuum chamber, and the high-frequency power source bias applying high-frequency power bias on the electrode substrate, and performing etching of the substrate mounted on the electrode substrate, and this installation contains:

the floating electrode, the opposite electrode substrate;

the high-frequency power source for supplying high frequency power to the floating electrode;

the solid material is located on the facing electrode substrate side of the floating electrode so as to be sprayed from the formation protects against etching film on the substrate; and

a control unit for controlling the high-frequency power supplied to the floating electrode for periodically spraying of solid material.

2. Installation of etching according to claim 1, which additionally includes means for introducing etching gas for introducing an etching gas, and a control unit configured to control the supply of high frequency power to the floating e is ectrode, by applying a high frequency power bias on the electrode substrate and the introduction of the etching gas in the vacuum chamber in sequence.

3. Installation of etching according to claim 2, in which the control unit has a capability of functioning in such a way as to introduce etching gas into the vacuum chamber at the time when the solid material is not sprayed.

4. Installation of etching according to claim 2, in which the control unit has a capability of functioning to introduce etching gas into the vacuum chamber at the time when the solid material is not sprayed or when the electrode substrate is not supplied high-frequency power offset.

5. Installation of etching according to claim 2, in which the control unit has a capability of functioning in such a way as to apply high-frequency power bias on the electrode substrate after the solid material is sprayed.

6. Installation of etching according to claim 1, in which the high-frequency power source connected to the floating electrode through a switch or Mariconda, as well as with plasmagenericshell funds to be used for generating plasma, and a control unit configured to control the switch or Mariconda, depending on what is appropriate, therefore, to apply high frequency power to survive the Mering electrode spraying of solid material.

7. Installation of etching according to claim 6, in which the control unit is arranged to control the high-frequency power source so that the output power of the source is varied during the spraying of solid material during the etching of the substrate.

8. Installation of etching according to claim 1, in which the solid material for forming protecting against etching of a film selected from a fluorine-containing polymer, silicon, carbon, silicon carbide, silicon oxide and silicon nitride.

9. Installation of etching according to claim 1, in which the solid material is a silicon, and continuously introduced etching gas and the oxide.

10. Installation of etching according to claim 1, in which the substrate is a silicon substrate.

11. Installation of etching according to claim 1, in which the substrate is a quartz substrate.

12. The etching method for etching the substrate placed in the vacuum chamber by generating plasma, and this method includes executing repetitive follows:

the step of etching the substrate on which the substrate is hounded by introducing etching gas into the vacuum chamber;

the step of forming the protecting against etching film on the substrate to form protects against etching of the film by sputtering the solid material opposite the substrate; and

13. The method of etching according to item 12, in which at the stage of formation protects against etching of the film as the spray gas is an inert gas.

14. The method of etching according to item 12, in which the step of etching the substrate using a mixture of inert gas and the etching gas.

15. The method of etching according to item 12, in which at the stage of removal protects against etching film is an inert gas or mixture of inert gas and the etching gas.

16. The method of etching according to item 12, which is injected at each stage of etching of the substrate, the step of forming the protecting against etching film and stage removal protects against etching the film in a vacuum chamber defined inert gas, and the fact that the inert gas type etching gas for the formation of the gas mixture used during etching of the substrate or the step of etching the substrate and the step of removing protecting against etching of the film.

17. The method of etching according to item 13, in which an inert gas selected from Ar, Xe, Kr and N2.

18. The method of etching according to item 12, in which the etching gas selected from SF6, NF3F2, SiF4and XeF2.

19. Method of etching pop, in which the step of etching the substrate is performed without supplying high-frequency power bias on the electrode substrate.

20. The method of etching according to item 12, in which the solid material is selected from a fluorine-containing polymer, silicon, carbon, and silicon carbide.

21. The method of etching according to item 12, in which the solid material is silicon, and the step of forming the protecting against etching film continuously introducing etching gas and oxygen.

22. The method of etching according to item 12, in which the substrate is a silicon.



 

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EFFECT: facilitated procedure, enhanced economic efficiency and yield due to high reproducibility.

37 cl, 5 dwg

FIELD: microelectronics, micro- and nano-technology.

SUBSTANCE: proposed method for producing submicron and nanometric structure includes formation of embossed structures on substrate surface, application of film to reduce embossed structure size to submicron and nanometric dimensions, and etching, anisotropic and selective relative to film material and source embossed layer, in chemically active plasma of structure obtained together with substrate material until embossed structure of submicron and nanometric dimensions, twice as deep as its width, is obtained.

EFFECT: provision for transferring mask pattern to bottom layer of substrate measured in terms of submicron and nanometric values.

2 cl, 3 dwg

FIELD: engineering of semiconductor devices.

SUBSTANCE: invention concerns method and device for etching dielectric, removing etching mask and cleaning etching chamber. In etching chamber 40 semiconductor plate 56 is positioned. Dielectric 58 made on semiconductor plate is subjected to etching, using local plasma, produced by special device for producing local plasma during etching process. Mask for etching 60 is removed by means of plasma from autonomous source 54, generated in device for producing plasma from autonomous source connected to etching chamber. Etching chamber after removal of semiconductor plate is subjected to cleaning, using either local plasma, or plasma from autonomous source. To achieve higher level of cleaning, it is possible to utilize a heater, providing heating for chamber wall.

EFFECT: increased efficiency.

2 cl, 4 dwg

FIELD: process equipment for manufacturing semiconductor devices.

SUBSTANCE: plasma treatment chamber 200 affording improvement in procedures of pressure control above semiconductor wafer 206 is, essentially, vacuum chamber 212, 214, 216 communicating with plasma exciting and holding device. Part of this device is etching-gas source 250 and outlet channel 260. Boundaries of area above semiconductor wafer are controlled by limiting ring. Pressure above semiconductor wafer depends on pressure drop within limiting ring. The latter is part of above-the-wafer pressure controller that provides for controlling more than 100% of pressure control area above semiconductor wafer. Such pressure controller can be made in the form of three adjustable limiting rings 230, 232, 234 and limiting unit 236 on holder 240 that can be used to control pressure above semiconductor wafer.

EFFECT: enhanced reliability of pressure control procedure.

15 cl, 13 dwg

FIELD: plasma-chemical treatment of wafers and integrated circuit manufacture.

SUBSTANCE: proposed device that can be used in photolithography for photoresist removal and radical etching of various semiconductor layers in integrated circuit manufacturing processes has activation chamber made in the form of insulating pipe with working gas admission branch; inductor made in the form of inductance coil wound on part of pipe outer surface length and connected to high-frequency generator; reaction chamber with gas evacuating pipe, shielding screens disposed at pipe base, and temperature-stabilized substrate holder mounted in chamber base. In addition device is provided with grounded shield made in the form of conducting nonmagnetic cylinder that has at least one notch along its generating line and is installed between inductor and pipe; shielding screens of device are made in the form of set of thin metal plates arranged in parallel at desired angle to substrate holder within cylindrical holder whose inner diameter is greater than maximal diameter of wafers being treated. Tilting angle, quantity, and parameters of wafers are chosen considering the transparency of gas flow screen and ability of each wafer to overlap another one maximum half its area. In addition substrate holder is spaced maximum four and minimum 0.6 of pipe inner diameter from last turn of inductance coil; coil turn number is chosen to ensure excitation of intensive discharge in vicinity of inductor depending on generator output voltage and on inner diameter of pipe using the following equation:

where n is inductance coil turn number; U is generator output voltage, V; Dp is inner diameter of pipe, mm.

EFFECT: enhanced speed and quality of wafer treatment; reduced cost due to reduced gas and power requirement for wafer treatment.

1 cl, 6 dwg, 1 tbl

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for purifying octafluoropropane. Method is carried out by interaction of crude octafluoropropane comprising impurities with the impurity-decomposing agent at increased temperature and then with adsorbent that are able to remove indicated impurities up to the content less 0.0001 wt.-% from indicated crude octafluoropropane. The impurity-decomposing agent comprises ferric (III) oxide and compound of alkaline-earth metal in the amount from 5 to 40 wt.-% of ferric oxide and from 60 to 95 wt.-% of compound of alkaline-earth metal as measured for the complete mass of the impurity-decomposing agent. Ferric (III) oxide represents γ-form of iron hydroxyoxide and/or γ-form of ferric (III) oxide. Impurities represent at least one compound taken among the group consisting of chloropentafluoroethane, hexafluoropropene, chlorotrifluoromethane, dichlorodifluoromethane and chlorodifluoromethane. Adsorbent represents at least one substance taken among the group consisting of activated coal, molecular sieves and carbon molecular sieves. Crude octafluoropropane comprises indicated impurities in the amount from 10 to 10 000 mole fr. by mass. Invention proposes gas, etching gas and purifying gas comprising octafluoropropane with purity degree 99.9999 wt.-% and above and containing chlorine compound in the concentration less 0.0001 wt.-%. Invention provides enhancing purity of octafluoropropane.

EFFECT: improved purifying method.

13 cl, 11 tbl, 12 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for purifying octafluorocyclobutane. Method is carried out by interaction of crude octafluorocyclobutane containing impurities with the impurity-decomposing agent at increased temperature and then with adsorbent that is able to eliminate indicated impurities up to the content less 0.0001 wt.-% from the mentioned crude octafluorocyclobutane. Impurity-decomposing agent comprises ferric (III) oxide and compound of alkaline-earth metal in the amount from 5 to 40 wt.-% of ferric oxide and from 60 to 95 wt.-% of compound of alkaline-earth metal as measured for the complete mass of the impurity-decomposing agent. Ferric (III) oxide represents γ-form of iron hydroxyoxide and/or γ-form of ferric (III) oxide. Impurity represents at least one fluorocarbon taken among the group consisting of 2-chloro-1,1,1,2,3,3,3-heptafluoropropane, 1-chloro-1,1,2,2,3,3,3-heptafluoropropane, 1-chloro-1,1,2,2,3,3,3-heptafluoropropane, 1-chloro-1,2,2,2-tetrafluoroethane, 1-chloro-1,1,2,2-tetrafluoroethane, 1,2-dichloro-1,1,2,2-tetrafluoroethane, hexafluoropropene and 1H-heptafluoropropane. Adsorbent represents at least one of representatives taken among the group including activated carbon, carbon molecular sieves and activated coal. Crude octafluorocyclobutane interacts with the mentioned impurity-decomposing agent at temperature from 250oC to 380oC. Invention proposes gas, etching gas and purifying gas including octafluorocyclobutane with purity degree 99.9999 wt.-% and above and comprising fluorocarbon impurity in the concentration less 0.0001 wt.-%. Invention provides enhancing purity of octafluorocyclobutane.

EFFECT: improved purifying method.

26 cl, 13 tbl, 10 ex

The invention relates to microelectronics, and more particularly to a technique of manufacturing solid-state devices and integrated circuits using microwave plasma stimulation under conditions of electron cyclotron resonance (ECR), as well as to technology plasma treatment in the process of manufacturing various semiconductor structures

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for purifying octafluorocyclobutane. Method is carried out by interaction of crude octafluorocyclobutane containing impurities with the impurity-decomposing agent at increased temperature and then with adsorbent that is able to eliminate indicated impurities up to the content less 0.0001 wt.-% from the mentioned crude octafluorocyclobutane. Impurity-decomposing agent comprises ferric (III) oxide and compound of alkaline-earth metal in the amount from 5 to 40 wt.-% of ferric oxide and from 60 to 95 wt.-% of compound of alkaline-earth metal as measured for the complete mass of the impurity-decomposing agent. Ferric (III) oxide represents γ-form of iron hydroxyoxide and/or γ-form of ferric (III) oxide. Impurity represents at least one fluorocarbon taken among the group consisting of 2-chloro-1,1,1,2,3,3,3-heptafluoropropane, 1-chloro-1,1,2,2,3,3,3-heptafluoropropane, 1-chloro-1,1,2,2,3,3,3-heptafluoropropane, 1-chloro-1,2,2,2-tetrafluoroethane, 1-chloro-1,1,2,2-tetrafluoroethane, 1,2-dichloro-1,1,2,2-tetrafluoroethane, hexafluoropropene and 1H-heptafluoropropane. Adsorbent represents at least one of representatives taken among the group including activated carbon, carbon molecular sieves and activated coal. Crude octafluorocyclobutane interacts with the mentioned impurity-decomposing agent at temperature from 250oC to 380oC. Invention proposes gas, etching gas and purifying gas including octafluorocyclobutane with purity degree 99.9999 wt.-% and above and comprising fluorocarbon impurity in the concentration less 0.0001 wt.-%. Invention provides enhancing purity of octafluorocyclobutane.

EFFECT: improved purifying method.

26 cl, 13 tbl, 10 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for purifying octafluoropropane. Method is carried out by interaction of crude octafluoropropane comprising impurities with the impurity-decomposing agent at increased temperature and then with adsorbent that are able to remove indicated impurities up to the content less 0.0001 wt.-% from indicated crude octafluoropropane. The impurity-decomposing agent comprises ferric (III) oxide and compound of alkaline-earth metal in the amount from 5 to 40 wt.-% of ferric oxide and from 60 to 95 wt.-% of compound of alkaline-earth metal as measured for the complete mass of the impurity-decomposing agent. Ferric (III) oxide represents γ-form of iron hydroxyoxide and/or γ-form of ferric (III) oxide. Impurities represent at least one compound taken among the group consisting of chloropentafluoroethane, hexafluoropropene, chlorotrifluoromethane, dichlorodifluoromethane and chlorodifluoromethane. Adsorbent represents at least one substance taken among the group consisting of activated coal, molecular sieves and carbon molecular sieves. Crude octafluoropropane comprises indicated impurities in the amount from 10 to 10 000 mole fr. by mass. Invention proposes gas, etching gas and purifying gas comprising octafluoropropane with purity degree 99.9999 wt.-% and above and containing chlorine compound in the concentration less 0.0001 wt.-%. Invention provides enhancing purity of octafluoropropane.

EFFECT: improved purifying method.

13 cl, 11 tbl, 12 ex

FIELD: plasma-chemical treatment of wafers and integrated circuit manufacture.

SUBSTANCE: proposed device that can be used in photolithography for photoresist removal and radical etching of various semiconductor layers in integrated circuit manufacturing processes has activation chamber made in the form of insulating pipe with working gas admission branch; inductor made in the form of inductance coil wound on part of pipe outer surface length and connected to high-frequency generator; reaction chamber with gas evacuating pipe, shielding screens disposed at pipe base, and temperature-stabilized substrate holder mounted in chamber base. In addition device is provided with grounded shield made in the form of conducting nonmagnetic cylinder that has at least one notch along its generating line and is installed between inductor and pipe; shielding screens of device are made in the form of set of thin metal plates arranged in parallel at desired angle to substrate holder within cylindrical holder whose inner diameter is greater than maximal diameter of wafers being treated. Tilting angle, quantity, and parameters of wafers are chosen considering the transparency of gas flow screen and ability of each wafer to overlap another one maximum half its area. In addition substrate holder is spaced maximum four and minimum 0.6 of pipe inner diameter from last turn of inductance coil; coil turn number is chosen to ensure excitation of intensive discharge in vicinity of inductor depending on generator output voltage and on inner diameter of pipe using the following equation:

where n is inductance coil turn number; U is generator output voltage, V; Dp is inner diameter of pipe, mm.

EFFECT: enhanced speed and quality of wafer treatment; reduced cost due to reduced gas and power requirement for wafer treatment.

1 cl, 6 dwg, 1 tbl

FIELD: process equipment for manufacturing semiconductor devices.

SUBSTANCE: plasma treatment chamber 200 affording improvement in procedures of pressure control above semiconductor wafer 206 is, essentially, vacuum chamber 212, 214, 216 communicating with plasma exciting and holding device. Part of this device is etching-gas source 250 and outlet channel 260. Boundaries of area above semiconductor wafer are controlled by limiting ring. Pressure above semiconductor wafer depends on pressure drop within limiting ring. The latter is part of above-the-wafer pressure controller that provides for controlling more than 100% of pressure control area above semiconductor wafer. Such pressure controller can be made in the form of three adjustable limiting rings 230, 232, 234 and limiting unit 236 on holder 240 that can be used to control pressure above semiconductor wafer.

EFFECT: enhanced reliability of pressure control procedure.

15 cl, 13 dwg

FIELD: engineering of semiconductor devices.

SUBSTANCE: invention concerns method and device for etching dielectric, removing etching mask and cleaning etching chamber. In etching chamber 40 semiconductor plate 56 is positioned. Dielectric 58 made on semiconductor plate is subjected to etching, using local plasma, produced by special device for producing local plasma during etching process. Mask for etching 60 is removed by means of plasma from autonomous source 54, generated in device for producing plasma from autonomous source connected to etching chamber. Etching chamber after removal of semiconductor plate is subjected to cleaning, using either local plasma, or plasma from autonomous source. To achieve higher level of cleaning, it is possible to utilize a heater, providing heating for chamber wall.

EFFECT: increased efficiency.

2 cl, 4 dwg

FIELD: microelectronics, micro- and nano-technology.

SUBSTANCE: proposed method for producing submicron and nanometric structure includes formation of embossed structures on substrate surface, application of film to reduce embossed structure size to submicron and nanometric dimensions, and etching, anisotropic and selective relative to film material and source embossed layer, in chemically active plasma of structure obtained together with substrate material until embossed structure of submicron and nanometric dimensions, twice as deep as its width, is obtained.

EFFECT: provision for transferring mask pattern to bottom layer of substrate measured in terms of submicron and nanometric values.

2 cl, 3 dwg

FIELD: production of dirt-free laser mirrors.

SUBSTANCE: proposed method for producing dirt-free surfaces of materials chosen from group incorporating GaAs, GaAlAs, InGaAs, InGaAsP, and InGaAs on mirror facets of chip for GaAS based laser resonators includes shearing of laser mirror facet in ambient atmosphere incorporating normal air, dry air, or dry nitric media. Oxides and other pollutants produced in the course of ambient atmosphere impact on mirror facets are removed by dry etching in vacuum. Then natural nitride layer is grown on mirror facets using nitrogen treatment. Such facet treatment ensures minimized light absorption and surface recombination.

EFFECT: facilitated procedure, enhanced economic efficiency and yield due to high reproducibility.

37 cl, 5 dwg

FIELD: plasma reaction gas, its production and application.

SUBSTANCE: proposed plasma reaction gas has in its composition chain-structure perfluoroalkyne incorporating 5 or 6 atoms of carbon, preferably perfluorine-2-pentyne. This plasma reaction gas can be found useful for dry etching to produce precision structure, for plasma chemical precipitation from vapor phase, for producing thin film, and for plasma chemical incineration. Plasma reaction gas is synthesized by way of bringing dihydrofluoroalkyne or monohydroalkyne in contact with basic compound.

EFFECT: enhanced economic efficiency of highly selective gas production for plasma reaction on industrial scale.

18 cl

FIELD: electronics; semiconductor devices and methods for etching structures on their wafers.

SUBSTANCE: plasmochemical etching of material is conducted by way of acting on its surface with ion flow of plasma produced from plasma forming gas filling evacuated camber, electron beam being used to act upon plasma forming gas for plasma generation. Constant longitudinal magnetic field with flux density of 20-40 Gs is built on axis, plasma-generating gas pressure is maintained within chamber between 0.01 and 0.1 Pa, and electron beam at current density of 0.1-1 A/cm2 ensuring ignition of beam-plasma discharge is used. Etching condition (energy and ion current density) can be controlled ether by modulating electron beam with respect to speed or by varying potential of discharge collector.

EFFECT: enhanced etching efficiency (speed) and quality of etching structures on semiconductor material surface: high degree of etching anisotropy preventing etching under mask, minimized material structure radiation defects brought in during etching.

2 cl, 1 dwg

FIELD: physics; electricity.

SUBSTANCE: etching system contains plasma-generating facilities for plasma generating in vacuum chamber, high-frequency displacement voltage source, supplying high-frequency displacement voltage to electrode-substrate, floating electrode opposite to electrode-substrate in vacuum chamber and supported in floating condition by electric potential, solid material placed on the side of the floating electrode directed to electrode-substrate to form film layer protecting from etching, and control unit for periodic supply of high-frequency voltage to floating electrode. Etching method includes repetition, in specified sequence, of substrate etching stage by means of etching gas supplied to vacuum chamber, and film layer formation stage protecting substrate from etching by sputtering of solid material opposite to substrate.

EFFECT: high etching selectivity when using mask as well as production of anisotropic profile and great etching depth.

22 cl, 7 dwg

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