KR101034030B1 - Poly silicon deposition device - Google Patents

Abstract

PURPOSE: A poly silicon depositing apparatus is provided to reduce the amount of power used for initially heating a silicon core rod, thereby increasing power efficiency. CONSTITUTION: A reactor(110) comprises a gas inputting hole(111) and a gas outputting hole. An electrode(121) includes a first electrode and a second electrode which are separated each other. A gas heating unit(150) heats a reaction gas mixed with a carrier gas supplied to the gas inputting hole. A gas jetting unit(123) jets the reaction gas toward a silicon core rod unit. A pressure adjusting unit(160) adjusts the amount of the reaction gas outputted through the gas outputting hole to adjust internal gas pressure.

Description

POLY SILICON DEPOSITION DEVICE

The present invention relates to an apparatus for manufacturing polysilicon used as a main raw material in the semiconductor or photovoltaic industry, and more particularly, to a heating body used for reactor operating power and initial silicon core rod heating in producing polysilicon. The present invention relates to a polysilicon deposition apparatus capable of increasing the quality of silicon by reducing the amount of foreign substances generated during gas reaction.

In order to manufacture polycrystalline silicon (also called polysilicon), which is used as a main raw material in the semiconductor or photovoltaic industry, metal-grade silicon must be made by reducing and reacting quartz or sand with carbon. Metal grade silicon is again used as a raw material for solar cell substrates (SoG-Si) after further purification, and polysilicon of 11N or more is used as single crystal raw material (EG-Si) for semiconductor wafer manufacturing. Polysilicon manufacturing industry is directly related to industries such as fine chemicals / materials, optical communication, and organosilicon in addition to semiconductor and solar power generation.

Metal polysilicon refining methods include Siemens (Siemens) method, Fluidized bed (fluidized bed) method, VLD (Vapor-to-Liquid Deposition) method and the method of directly purifying metal grade silicon.

The most commonly used method is the Siemens method. In this method, polycrystalline silicon is prepared by pyrolyzing a reaction gas in which chlorosilane or monosilane is mixed with hydrogen and depositing it on a silicon core rod. In this method, the silicon core rod is electrically energized and heats the entire silicon core rod according to the heat of resistance. Since silicon has a very high electrical resistance at room temperature, electricity is not energized well. However, when the silicon is heated to about 1000 ° C, the electrical resistance is drastically lowered, so electricity is well supplied. Therefore, a means for heating the silicon core rods early in the polysilicon manufacturing process is needed.

Conventionally, as the process proceeds by maintaining the pressure inside the reactor at 4kgf / cm2 or more, the amount of gas required for maintaining pressure increases and the amount of power required for maintaining the temperature of the core rod is required as the pressure increases. In addition, a heating element was installed around the silicon core rod inside the reactor to generate electricity by flowing electricity to the heating element at the beginning of the process, and a method of raising the temperature of the silicon core rod according to the heat was used. However, this method has a problem that the reaction gas use efficiency is lowered because silicon is also deposited on the heating element, contamination by the heating element occurs, and there is a great inconvenience in cleaning and reusing after use.

The present invention has been proposed in the above background, and an object of the present invention is to provide a polysilicon deposition apparatus that can increase power efficiency by reducing the amount of power used to initially heat the silicon core rod.

Another object of the present invention is to provide a polysilicon deposition apparatus that can reduce the amount of foreign substances generated during silicon deposition, thereby increasing the convenience of product discharge and device maintenance.

In order to achieve the above object, the polysilicon deposition apparatus according to an aspect of the present invention, the reactor is a gas inlet for the reaction gas mixed with the carrier gas is injected and a gas outlet for discharging the gas to the outside, and the reactor A silicon core which is installed inside and is spaced apart by a predetermined distance, the electrode part including a first electrode and a second electrode, and receives a current from the first electrode of the electrode part and self-heats while conducting current to the second electrode of the electrode part. Rod,

A gas heating unit installed outside the reactor and heating the reaction gas mixed with the carrier gas supplied to the gas inlet of the reactor, and a reaction gas installed inside the reactor and heated in the gas heating unit and introduced through the gas inlet of the reactor Gas injection unit for injecting to flow toward the silicon core rod portion, and a pressure control unit for adjusting the gas pressure in the reactor by adjusting the amount of gas discharged through the gas outlet.

Polysilicon deposition apparatus according to an additional aspect of the present invention, the gas heating unit for supplying the source gas and the reaction gas supply gas, the gas flow rate control device for controlling the input amount of the carrier gas and the reaction gas introduced through the gas supply pipe and , A heating element for heating the reaction gas mixed with the carrier gas introduced through the gas supply pipe.

According to the above configuration, the polysilicon deposition apparatus of the present invention is implemented by including a pressure control unit for adjusting the gas pressure in the reactor and a gas heating unit for heating the reaction gas supplied into the reactor, the heated reaction gas is inside the reactor Influence in the reactor has a useful effect of increasing power efficiency by reducing the internal pressure of the reaction and the amount of power used to initially heat the silicon core rod.

In addition, the polysilicon deposition apparatus of the present invention can manufacture high quality polysilicon with low energy by removing device elements that may cause the generation of impurities when silicon is deposited inside the reactor, for example, a heating element installed in the conventional reactor. That has a useful effect.

1 is an embodiment showing a cross-sectional view of a polysilicon deposition apparatus according to the present invention,
FIG. 2 is a cross-sectional view taken along line AA of the first heating element 123a of the polysilicon deposition apparatus of FIG. 1;
3 shows a temperature distribution diagram of the silicon core rod according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

1 is an embodiment showing a cross-sectional view of the polysilicon deposition apparatus according to the present invention, Figure 2 is an exemplary view for explaining the pressure control unit 160 of the polysilicon deposition apparatus according to Figure 1, Figure 3 1 is an exemplary view for explaining the gas supply unit 170 of the polysilicon deposition apparatus according to FIG. 1.

First, as shown in FIG. 1, the polysilicon deposition apparatus 100 according to the present invention includes a gas inlet 111 into which a reaction gas mixed with a carrier gas is introduced and a gas outlet 112 through which gas is discharged to the outside. Polysilicon deposition unit 121 to 126 is formed in the reactor 110, the inner space of the reactor 110 is formed to deposit polysilicon by pyrolyzing the source gas supplied through the gas inlet 111, gas heating The unit 150, a pressure regulator 160, and a gas supply unit 170 are included. Here, the reaction gas is chlorosilane or monosilane, and the reaction gas is supplied mixed with a carrier gas such as hydrogen.

As shown in FIG. 1, for example, the gas outlet 112 is formed at an upper surface of the reactor 110. Accordingly, the silicon powder generated by the pyrolysis of the reaction gas is not deposited on the surface of the silicon core rods 124, 125, and 126, and is accumulated on the upper surface of the reactor 110, so that the silicon core rods 124, 125, and 126 are formed. It can prevent it from falling on the surface.

In one embodiment, the polysilicon deposition units 121 to 126 include the electrode units 121 and 122, the gas injection unit 123, and the silicon core rod units 124, 125 and 126. The electrode parts 121 and 122 are for supplying current to the silicon core rod parts 124, 125, and 126, and are installed on the bottom of the reactor 110 and spaced apart by a predetermined distance from the first electrode 121. The second electrode 121 is included. Here, the first electrode 121 and the second electrode 121 may be implemented as an electrode of graphite (graphite) material. In addition, the first electrode 121 and the second electrode 121 are installed to be insulated from the bottom of the reactor 110.

The gas injection unit 123 is installed inside the reactor 110, and the reaction gas, which is heated in the gas heating unit 150 and introduced through the gas inlet 111 of the reactor 110, is the silicon core rod unit 124. Spray to flow toward 125 and 126.

The silicon core rods 124, 125, and 126 receive current from the first electrode 121 to conduct current to the second electrode 121, and simultaneously heat self-heating and deposit silicon gas decomposed from the reaction gas. Play a role. The silicon core rod parts 124, 125, and 126 are connected to the first electrode 121 and are installed in a direction perpendicular to the bottom of the reactor 110 and the second electrode 121. And a third silicon core connecting the second silicon core rod 126 installed in a direction perpendicular to the bottom of the reactor 110 and connecting the first silicon core rod 124 and the second silicon core rod 126. A rod 125.

The gas heating unit 150 is installed outside the reactor 110 and heats the reaction gas in which the carrier gas supplied to the gas inlet 111 of the reactor 110 is mixed. Hereinafter, the gas heating unit 150 will be described with reference to FIG. 2. As shown in FIG. 2, the gas heating unit 150 includes gas supply pipes 151a and 151b for supplying a reaction gas and a carrier gas, a gas flow controller 152, a mixing device 153, and a heating element ( 154, the insulation 155, and the pipe 156 may be implemented.

The gas supply pipes 151a and 151b include a first gas supply pipe 151a to which a reaction gas is supplied and a second gas supply pipe 151b to which a carrier gas is supplied. The reaction gas is chlorosilane or monosilane, and the reaction gas is supplied mixed with a carrier gas such as hydrogen.

The gas flow rate controller 152 controls the amount of the carrier gas and the reactant gas introduced through the gas supply pipes 151a and 151b. The gas flow controller 152 may be implemented as, for example, a mass flow controller (MFC). The mass flow controller (MFC) includes a temperature sensor that detects a temperature change of the inner foil according to the flow of gas, and a valve controller that detects a current difference according to the temperature change from the temperature sensor and controls the solenoid valve.

The mixing device 153 mixes the carrier gas and the reaction gas supplied through the gas supply pipes 151a and 151b at a constant mixing ratio. In general, when the mixing ratio of the carrier gas and the reaction gas is not appropriate, the reaction does not sufficiently occur in the silicon core rod parts 124, 125, and 126, and impurities are generated. The mixing ratio of the carrier gas and the reaction gas may be 10: 1 mol to 100: 1 mol.

The heating element 154 heats the reaction gas in which the carrier gas introduced through the gas supply pipes 151a and 151b is mixed. The heating element 154 may be implemented as any one of a ceramic heater, an oil heater, and a metal heater. The heat insulator 155 insulates heat generated from the heat generating element 154. Pipe 156 is connected to the gas inlet (refer to 111 in Figure 1) of the reactor.

The pressure controller 160 controls the amount of gas discharged through the gas outlet 112 to control the gas pressure inside the reactor 110. Hereinafter, the pressure regulator 160 will be described with reference to FIG. 3. As shown in FIG. 3, the pressure regulator 160 includes a pressure detector 161, a valve 162, and a valve controller 163.

The pressure detector 161 detects the gas pressure inside the reactor 110 and may be implemented as a pressure detector that converts the distortion generated by the pressure into an electrical signal and outputs the electrical signal. The valve 162 is used to adjust the amount of gas discharged through the gas outlet 112. The valve controller 163 controls the operation of the valve 162 according to the electric signal input from the pressure detector 161. The valve controller 163 maintains the gas pressure in the reactor (reference numeral 110 in FIG. 1) at 1 kgf / cm 2 or more and below 4 kgf / cm 2. Here, the pressure control should be made in units of ± 0.01kgf / cm 2, and if the pressure is not finely controlled, variations occur in the amount of current and gas flowing through the silicon core rods 124, 125, and 126.

Referring back to FIG. 1, the reactor 110 includes a bottom cooling body 113 having a first cooling rod 113a installed therein, and first and second silicon core rods at one end of the bottom cooling body 113. 124 and 126 are installed in a direction parallel to the lower cooling body 114 having a second cooling rod 114a formed therein, and installed on an upper surface of the lower cooling body 114 and having third cooling rods therein, respectively. An upper cooling body 115 having a 115a formed therein, and a dome cooling body 116 installed above the upper cooling body 116 and having a fourth cooling rod 116a formed therein.

Although not shown in FIG. 1, the reactor 110 includes a cooling water supply device for supplying cooling water to each of the first to fourth cooling rods 113a to 116a. In a preferred embodiment, the cooling water supply device supplies the cooling water having the lowest temperature to the second cooling rod 114a among the first to fourth cooling rods 113a to 116a.

Most of the supplied reactant gas is pyrolyzed and deposited on the first and second silicon core rods 124 and 126, but some silicon powder is not deposited on the silicon first and second silicon core rods 124 and 126, but the reactor It may also be deposited inside 110. Since the deposition reaction of the silicon powder occurs easily where the temperature is low, the lowest temperature of the lower cooling body 114 is controlled to induce the deposition of the silicon powder on the lower cooling body 114. When a large amount of silicon powder is deposited on the dome cooler 116 or the upper coolant 115, it may adversely affect the quality of the silicon rod 210 and when a large amount of silicon powder is deposited on the bottom coolant 113. This is because there is a risk of blocking the gas injection unit 123.

In one embodiment, the polysilicon deposition apparatus 100 according to the present invention further includes a viewing window 117 to allow the inside of the reactor 110 to be identified from the outside. The sight glass 117 is for measuring the diameters of the silicon core rod parts 124, 125, and 126. For example, the viewing window 117 may be installed in the upper cooling body 115. In addition, since a large amount of silicon powder is deposited on the see-through window 117, it may be difficult to check the inside thereof, thereby attaching a hot wire to the glass of the see-through window 117 to increase the temperature to suppress the deposition of the silicon powder to the maximum, thereby facilitating the internal check. .

Thus far, the present specification has been described with reference to the embodiments shown in the drawings so that those skilled in the art can easily understand and reproduce the present invention, but this is merely exemplary, and the description Those skilled in the art will understand that various modifications and equivalent other embodiments are possible from the embodiments of the present invention. Accordingly, the true scope of the present invention should be determined only by the appended claims.

100: polysilicon deposition apparatus
110: reactor
111: gas inlet 112: gas outlet
113: bottom cooling body 113a: first cooling rod
114: lower cooling body 114a: second cooling rod
115: upper cooling body 115a: third cooling rod
116: dome cooling body 116a: fourth cooling rod
117: viewing window
121: first electrode 122: second electrode
123: gas injection unit
124: first silicon core rod 125: third silicon core rod
126: second silicon core rod

Claims (12)

A polysilicon deposition apparatus for depositing polysilicon by pyrolyzing a reaction gas mixed with a carrier gas,
A reactor in which a gas inlet through which a reaction gas mixed with a carrier gas is input and a gas outlet through which the reaction gas is discharged are formed;
An electrode unit installed inside the reactor and including a first electrode and a second electrode spaced apart by a predetermined distance;
A silicon core rod unit which receives current from the first electrode and heats itself while supplying current to the second electrode;
A gas heater disposed outside the reactor and connected to the gas inlet and heating the reaction gas mixed with a carrier gas supplied to the gas inlet;
A gas injector installed in the reactor and configured to inject the reaction gas, which is heated in the gas heating unit, and injected through the gas inlet toward the silicon core rod unit; And
A pressure controller configured to adjust an amount of the reaction gas discharged through the gas outlet, thereby controlling a gas pressure inside the reactor;
Including,
The gas heating unit,
A first gas supply pipe for supplying the reaction gas,
A second gas supply pipe for supplying the carrier gas,
A gas flow rate control device installed in the first gas supply pipe and the second gas supply pipe and controlling a flow rate of the reaction gas and the carrier gas;
A mixing device connected to the first gas supply pipe and the second gas supply pipe, and mixing the reaction gas and the carrier gas supplied through the first gas supply pipe and the second gas supply pipe, respectively;
A pipe connecting the mixing device and the gas inlet,
A heating element installed around the pipe and heating the reaction gas and the carrier gas mixed and discharged by the mixing device, and
Is formed in a form surrounding the heating element and is formed including a heat insulating material to insulate the heating element and the outside,
The pressure control unit,
A pressure detector for detecting a gas pressure inside the reactor;
A valve installed at the gas outlet and controlling an amount of gas discharged through the gas outlet;
And a valve controller for controlling the operation of the valve in accordance with the electrical signal input from the pressure detector. The method of claim 1, wherein the silicon core rod portion:
A first silicon core rod connected to the first electrode of the electrode unit and installed in a direction perpendicular to the bottom of the reactor;
A second silicon core rod connected to the second electrode of the electrode unit and installed in a direction perpendicular to the bottom of the reactor; And
A third silicon core rod connecting the first silicon core rod and the second silicon core rod;
Polysilicon deposition apparatus comprising a. delete delete delete The method of claim 1,
The mixing ratio of the carrier gas and the reaction gas is 10: 1 (mol) to 100: 1 (mol) characterized in that the polysilicon deposition apparatus. delete The method of claim 1,
The heating element,
Polysilicon deposition apparatus characterized in that any one of a ceramic heater, an oil heater, a metal heater. The method of claim 1,
The pressure control unit,
Polysilicon deposition apparatus characterized in that for maintaining the gas pressure in the reactor to 1kgf / ㎠ or more, less than 4kgf / ㎠. The reactor of claim 1 wherein the reactor is:
A bottom cooling body provided with a first cooling rod therein;
A lower cooling body installed in a direction perpendicular to one end of the bottom cooling body and having a second cooling rod formed therein;
An upper cooling body installed on an upper surface of the lower cooling body and having third cooling rods formed therein;
A dome cooling body installed on an upper surface of the upper cooling body and having a fourth cooling rod formed therein; And
Includes; a cooling water supply device for supplying cooling water to each of the first to fourth cooling rods,
Here, the cooling water supply device polysilicon deposition apparatus characterized in that for supplying the cooling water having the lowest temperature to the second cooling rod of the lower cooling body of the first to fourth cooling rods. The reactor of claim 10 wherein the reactor is:
A viewing window for allowing the inside of the reactor to be checked from the outside; And
A heating wire attached to the viewing window;
Polysilicon deposition apparatus further comprising a. The method of claim 1,
The gas outlet is a polysilicon deposition apparatus, characterized in that formed on the upper surface of the reactor.

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