HVPE reactor exhaust system

Abstract

The present invention relates to an exhaust device for an HVPE reactor, and is characterized by comprising an intake part connected to an exhaust pipe of the HVPE reactor, an exhaust part through which residual gas flowing in from the intake part is exhausted, and an injection part provided in the intake part to intake a fluid and inject the fluid in the exhaust direction of the residual gas.

Description

[Technical Field]

[0001] The present invention relates to an exhaust system for an HVPE reactor, and more particularly to an exhaust system for an HVPE reactor that prevents clogging of the reactor due to parasitic deposition, thereby enabling long-term operation of the reactor. [Background technology]

[0002] Hydride Vapor Phase Epitaxy (HVPE) is a method that uses ammonia, hydrogen, and various chloride gases as sources to form a relatively thick (tens to hundreds of μm) compound layer on a substrate.

[0003] HVPE has a faster growth rate for gallium nitride (GaN) than MECVD (Metalorganic Chemical Vapor Deposition), and can also be used to grow gallium oxide and indium phosphide thin films.

[0004] Conventional HVPE reactors designed for GaN growth suffer from the problem of parasitic deposition of substances (e.g., NH4Cl, GaCl3) near the process gas outlet and on the internal surfaces near the reactor outlet. The ammonium chloride discharged from the outlet precipitates at temperatures below about 300°C.

[0005] These parasitic deposits (solid compounds) rapidly reduce the reactor's performance. To address this issue, a vacuum pump can be installed to reduce pressure, but this can clog the pump, making it difficult to use. To prevent clogging, a large condensing chamber can be installed in front of the pump, but this merely acts as a trap for residual gases and does not substantially solve the main problem.

[0006] Therefore, there is a need to improve this.

[0007] The background art of the present invention is disclosed in Korean Patent Publication No. 10-2010-0100910 (published on September 15, 2010, title of invention: HVPE reactor device). Summary of the Invention [Problem to be solved by the invention]

[0008] SUMMARY OF THE INVENTION An object of the present invention is to provide an exhaust system for an HVPE reactor that prevents clogging of the reactor due to parasitic deposition and allows for long-term operation of the reactor.

[0009] An object of the present invention is to provide an exhaust system for an HVPE reactor that allows easy adjustment of pressure and the amount and speed of exhaust of residual gases. [Means for solving the problem]

[0010] The exhaust device for an HVPE reactor according to the present invention may include an intake section connected to an exhaust pipe of the HVPE reactor, an exhaust section through which residual gas flowing in from the intake section is exhausted, and an injection section provided in the intake section to intake a fluid and inject the fluid in the exhaust direction of the residual gas.

[0011] The exhaust may include a venturi tube.

[0012] The injection unit may include a fluid supply unit that supplies the fluid, a compressor that compresses the fluid supplied from the fluid supply unit, and an ejector connected to the compressor that injects the compressed fluid at high speed in a direction in which the residual gas is exhausted.

[0013] The amount and speed of the residual gas discharged can be adjusted according to the compression ratio of the compressor.

[0014] The amount and speed of the residual gas exhausted can be adjusted by adjusting the distance between the ejector and the exhaust unit.

[0015] The distance between the ejector and the exhaust unit may be adjustable by a position adjustment unit that changes the position of the ejector.

[0016] The position adjusting portion may include a nut portion formed on the suction portion, and a bolt portion formed on the ejector to be threadedly coupled to the nut portion.

[0017] The position adjustment unit may include a slide rail unit formed on the suction unit, a slide member formed on the ejector to be slidably coupled to the slide rail unit, and a locking unit to fix the slide member to the slide rail unit.

[0018] The ejector may include a plurality of injection ports connected to the compressor, and an on-off valve configured to block the flow of the fluid through the injection ports.

[0019] The injection port may include a main injection port formed at a center of the ejector, and a plurality of auxiliary injection ports provided in a radial direction of the main injection port.

[0020] A bubbler may be provided at the rear end of the exhaust unit to prevent the residual gas from flowing back.

[0021] The inner circumferential surface of the exhaust portion may be provided with a steel wire having a spiral groove, thereby improving the exhaust performance of residual gases and fluids. [Effects of the Invention]

[0022] The exhaust system for an HVPE reactor according to the present invention prevents clogging of the reactor due to parasitic deposition, enabling long-term operation of the reactor.

[0023] The present invention can easily adjust the discharge amount and discharge speed of residual gas by adjusting the compression ratio of the compressor or the distance between the ejector and the discharge part, and can be adapted to suit various situations, providing convenience in use.

[0024] The present invention has a simple structure of the intake section, the injection section, and the exhaust section, which reduces manufacturing costs and allows for weight reduction. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a schematic diagram of an HVPE reactor according to one embodiment of the present invention;

[0026] [Figure 2] FIG. 1 shows an exhaust system for an HVPE reactor according to one embodiment of the present invention.

[0027] [Figure 3] 1 is a diagram illustrating an injection section of an exhaust device of an HVPE reactor according to an embodiment of the present invention.

[0028] [Figure 4] 3 is a cross-sectional view taken along the line A-A in FIG. 2.

[0029] [Figure 5] FIG. 1 is a diagram illustrating a first modified example of an exhaust device for an HVPE reactor according to an embodiment of the present invention.

[0030] [Figure 6] 6 is a cross-sectional view taken along the line A-A in FIG. 5.

[0031] [Figure 7] FIG. 10 is a diagram illustrating a second modified example of the exhaust device of the HVPE reactor according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] Hereinafter, an embodiment of an exhaust device for an HVPE reactor according to the present invention will be described with reference to the accompanying drawings.

[0033] In this process, the thickness of lines and the sizes of components shown in the drawings may be exaggerated for clarity and convenience of explanation. The terms described below are defined in consideration of the functions in the present invention, and may vary depending on the intentions or practices of users or operators. Therefore, the definitions of these terms should be based on the contents of the entire specification.

[0034] In this specification, when a part is said to be "coupled (or connected)" to another part, this includes not only the case where it is "directly coupled (or connected)" but also the case where it is "indirectly coupled (or connected)" with another member interposed therebetween. In this specification, when it is said that a part "includes (or comprises)" a certain component, this does not mean that it excludes other components, but that it can further "include (or comprise)" other components, unless otherwise specified to the contrary.

[0035] The same reference numbers may refer to the same components throughout this specification. Even if the same or similar reference numbers are not mentioned or described in a particular drawing, the numbers may be described based on other drawings. Even if a part in a particular drawing does not have a reference number, the part may be described based on other drawings. The number, shape, size, and relative differences in size of detailed components included in the drawings of this application are set for ease of understanding and may be embodied in various forms without limiting the embodiments.

[0036] Fig. 1 is a diagram showing a schematic diagram of an HVPE reactor according to one embodiment of the present invention. Fig. 2 is a diagram showing an exhaust system of an HVPE reactor according to one embodiment of the present invention. Fig. 3 is a diagram for explaining an injection part of an exhaust system of an HVPE reactor according to one embodiment of the present invention. Fig. 4 is a cross-sectional view taken along line A-A in Fig. 3.

[0037] 1, the HVPE reactor 1 can be divided into a reaction section 10 and an exhaust system 100. The reaction section 10 is divided into a source region A where gas is supplied and a growth region B where a susceptor 14 is located, and all internal components are made of quartz tubes.

[0038] The source region A is formed in a tubular shape, and is connected to an HCl gas supply pipe 11 for supplying HCl gas, and a source boat 12 is disposed therein. Gallium (Ga) metal, which is a precursor, is positioned in the source boat 12.

[0039] A carrier gas supply pipe 13 for introducing a carrier gas is connected to the source region A, and the downstream discharge portion of the source region A for discharging GaCl gas is tapered and reduced in diameter.

[0040] Growth region B is where the actual reaction for growing gallium oxide occurs, and contains a susceptor 14 on which a target substrate is mounted. For homoepitaxy, a substrate (e.g., sapphire or SiC) is used.

[0041] The substrate can be fixed to a rod and connected to a motor to rotate during processing.

[0042] During thin film growth, a doping gas is injected to adjust the concentration of carriers and transport them.

[0043] Looking at the reactions in each region, in the source region (A), a quartz tube is heated to 700-900°C by a heater h to grow gallium nitride (GaN). When chlorine (HCl) gas supplied from an HCl gas supply pipe 11 is injected onto a source boat 12 filled with gallium (99.9999%), a high-purity precursor, the two substances react with gallium metal to produce gallium chloride (GaCl) gas and hydrogen (H2) gas.

[0044] 2HCl+2Ga → 2GaCl+H2

[0045] The gallium chloride thus formed is transported to a substrate section within the source tube by a carrier gas supplied from a carrier gas supply pipe 13 .

[0046] When ammonia (NH3) gas is supplied into the reaction section 10 from the ammonia supply pipe 15, the two gases are adsorbed onto the substrate (e.g., sapphire, SiC) inside the quartz tube heated to 900 to 1,100°C, thermally decomposed, and bonded to form and grow a GaN thin film.

[0047] NH3+GaCl→GaN+H2+HCl

[0048] After gallium nitride is produced, hydrogen chloride (HCl) and ammonia (NH3) remaining in the reactor react to produce ammonium chloride (NH4Cl) and gallium chloride (GaCl3). These ammonium chloride and gallium chloride are discharged through exhaust pipe 16 together with carrier gases such as hydrogen and nitrogen.

[0049] That is, residual chemical gases that are not involved in the formation of a thin film by pyrolysis must be discharged to the outside. At this time, residues from these residual gases become parasitic around the exhaust pipe 16, and therefore, these must be quickly discharged outside the reactor.

[0050] The exhaust device 100 of the HVPE reactor 1 according to one embodiment of the present invention can quickly exhaust the residual gas as described above, and can function as a configuration that prevents clogging of the exhaust pipe 16.

[0051] 1 to 4, an exhaust device 100 for an HVPE reactor according to one embodiment of the present invention may include an intake section 110, an exhaust section 120, and an injection section .

[0052] The intake section 110 is connected to the exhaust pipe 16 of the HVPE reactor 1. The intake section 110 may be directly connected to the end of the exhaust pipe 16 and bound thereto.

[0053] As shown in FIG. 2, the exhaust unit 120 can function as a passageway for discharging the residual gas that has flowed into the intake unit 110 to the outside by exhausting the residual gas that has flowed into the intake unit 110.

[0054] The exhaust unit 120 may be formed as a Venturi tube 125. That is, the exhaust unit 120 may be formed in a tube shape in which the passage of the exhaust unit 120 gradually narrows and then widens again. This structural feature allows the speed of the remaining gas passing through the exhaust unit 120 and the speed of the fluid in the injection unit 130, which will be described later, to be accurately measured.

[0055] 4, a steel wire 127 formed with a spiral groove is formed on the inner circumferential surface of the exhaust part 120, thereby improving the exhaust performance of residual gases and fluids. The steel wire 127 allows the residual gases and fluids exhausted through the exhaust part 120 to form a tornado, thereby improving the exhaust performance.

[0056] The injection unit 130 is provided in the suction unit 110 and functions as a component that sucks in a fluid and injects the fluid in the direction of exhaust of the residual gas, thereby injecting the fluid at high speed to generate a pressure difference and sucking the residual gas in the exhaust pipe 16 into the suction unit 110 and smoothly discharging it.

[0057] As an example, the injection unit 130 may include a fluid supply unit 132 that supplies a fluid, a compressor 134 that compresses the fluid supplied from the fluid supply unit 132, and an ejector 135 that is connected to the compressor 134 and injects the compressed fluid at high speed in the exhaust direction of the residual gas.

[0058] The fluid supply 132 may comprise a tank containing a fluid, which may include steam, water, and gas.

[0059] The compressor 134 can function as a component that compresses the fluid to a high pressure and supplies it to the ejector 135 .

[0060] The ejector 135 is coupled to the intake section 110 and is disposed so that the direction of fluid injection faces the exhaust section 120, and ejects the fluid transmitted through the compressor 134 at high speed.

[0061] When the fluid is ejected at high speed through the ejector 135, the pressure on the outlet side of the ejector 135 decreases, and due to this pressure difference, the remaining gas discharged to the exhaust pipe 16 of the HVPE reactor 1 connected to the suction section 110 is sucked into the suction section 110.

[0062] The inhaled residual gas is mixed with the fluid in the intake section 110, and the velocity energy of the residual gas and the fluid is converted into pressure energy as they flow to the exhaust section 120, allowing the residual gas and the fluid to be discharged.

[0063] Therefore, by enabling smooth discharge of residual gas and preventing the occurrence of parasitic deposits, clogging of the exhaust pipe 16 can be prevented, and the performance degradation of the reactor 1 can be prevented.

[0064] The exhaust system 100 for the HVPE reactor according to this embodiment can adjust the exhaust volume and speed of the residual gases.

[0065] This means that the discharge amount and discharge speed of the residual gas can be adjusted according to the compression ratio of the compressor 134. That is, by adjusting the compression ratio of the compressor 134 and thereby adjusting the outlet side pressure of the ejector 135, the discharge amount and discharge speed of the residual gas can be adjusted.

[0066] As shown in FIG. 3, the amount and speed of the residual gas exhausted can be adjusted by adjusting the distance between the ejector 135 and the exhaust unit 120 .

[0067] More specifically, the distance d between the ejector 135 and the exhaust unit 120 can be adjusted by a position adjustment unit 140 that changes the position of the ejector 135. As an example, the position adjustment unit 140 may include a nut portion 142 formed on the suction unit 110 and a bolt portion 144 formed on the ejector 135 to be threadedly coupled to the nut portion 142.

[0068] The ejector 135 and the suction section 110 are screwed together by a bolt section 144 and a nut section 142, and the distance between the inlet side of the exhaust section 120 and the outlet side of the ejector 135 can be adjusted depending on the degree of screw tightening.

[0069] In this embodiment, the distance is adjusted by screwing the suction portion 110 and the ejector 135 together, but this is not limiting, and various design modifications are possible that allow the position of the ejector 135 to be changed.

[0070] A bubbler 150 for preventing backflow of residual gas may be provided at the rear end of the exhaust unit 120, and a tank 160 containing a dissolving fluid capable of dissolving residual gas may be provided at the rear end of the bubbler 150.

[0071] The bubbler 150 can serve as a configuration for venting residual gases during purging of the reactor 1 or in other situations where the exhaust system 100 is not used.

[0072] Aqueous ammonium chloride solutions and other waste products can be very harmful to parts of the reactor 1, and during low process gas flows, vapor backflow of these solutions can have a negative effect on the growth process, so this can be prevented via the bubbler 150.

[0073] The dissolving fluid in the tank 160 may be water, and although the present embodiment uses water as the dissolving fluid, any other suitable fluid or aqueous solution of a suitable reagent may be used instead of water. For example, HCl, ammonia gas, and ammonium chloride may be dissolved more efficiently by some other alcohols than by water.

[0074] FIG. 5 is a diagram showing a first modified example of the exhaust device 100 for the HVPE reactor according to one embodiment of the present invention, and FIG. 6 is a diagram showing the line BB in FIG.

[0075] 5 and 6, the ejector 235 may be formed with a plurality of jets 236 connected to the compressor 134.

[0076] The injection port 236 may include a main injection port 237 formed in the center of the ejector 235 and a plurality of auxiliary injection ports 238 provided in the radial direction of the main injection port 237 .

[0077] In this case, the main injection port 237 and the auxiliary injection port 238 may be connected to the compressor 134, and the main injection port 237 may be connected to the compressor 134, and the auxiliary injection port 238 may be connected to the outside, so that outside air can flow in through the auxiliary injection port 238 when injection is performed through the main injection port 237.

[0078] For example, the amount and speed of the residual gas discharged can be changed depending on the number of injection ports 236 formed in the ejector 235 .

[0079] An on-off valve v for turning on and off the flow of fluid may be provided to the multiple injection ports 236. A plurality of on-off valves v may be provided to open and close each injection port 136.

[0080] By turning on and off the flow of fluid using this on-off valve v, the amount and speed of exhaust of residual gas can be adjusted.

[0081] The ejector 235 is slidably coupled to the suction portion 110 , and the distance between the ejector 235 and the exhaust portion 120 can be adjusted by a position adjustment portion 140 that changes the position of the ejector 135 .

[0082] The position adjustment part 140 may include a slide rail part 242 formed in the suction part 110, a slide member 244 formed in the ejector 135 so as to be slidably connected to the slide rail part 242, and a locking part 246 that fixes the slide member 244 to the slide rail part 242.

[0083] The slide rail portions 242 extend from the upper portion of the suction portion 110 and are formed opposite each other, the slide members 244 are formed to protrude from both sides of the ejector 235 and are coupled to penetrate the slide rail portions 242 so as to slide, and the locking portion 246 may include a screw thread 247 formed on the outside of the slide rail portion 242 and a locking nut portion 248 that is screw-coupled to the screw thread 247.

[0084] The locking portion 246 can be modified into various shapes that can fix the slide member 244 in a specific position, and this is merely a matter of design modification.

[0085] FIG. 7 is a diagram illustrating a second modified example of the exhaust device 100 for the HVPE reactor according to one embodiment of the present invention.

[0086] 7, the inlet 110 and the exhaust 120 are directly connected and extend on the same line. That is, the exhaust pipe 16 of the reactor 1, the inlet 110, and the exhaust 120 extend on the same line, allowing for smoother exhaust of residual gases.

[0087] The ejector 335 may extend through the suction portion 110 and be bent so that the ejection direction of the ejector 335 is directed toward the exhaust portion 120 .

[0088] Therefore, the nozzle 336 of the ejector 135 is located at the center of the suction section 110, and when the fluid transmitted through the compressor 134 is injected at high speed, the pressure on the outlet side of the nozzle 336 of the ejector 335 decreases, and the residual gas discharged to the exhaust pipe 16 is sucked into the suction section 110, allowing the residual gas to be smoothly discharged through the exhaust section 120.

[0089] The ejector 335 is slidably coupled to the suction portion 110 , and the distance between the ejector 335 and the exhaust portion 120 can be adjusted by a position adjustment portion 240 that changes the position of the ejector 335 .

[0090] The position adjusting unit 240 according to the second modification can move the ejector 135 horizontally and has the same structure as the first modification, so detailed description thereof will be omitted. The position adjusting unit 240 can also adjust the amount and speed of exhaust of residual gas by adjusting the distance between the ejector 335 and the exhaust unit 120.

[0091] According to the present invention, residual gas generated in the reactor can be smoothly discharged, and clogging of the reactor due to parasitic deposition can be prevented, thereby enabling the reactor to operate for a long period of time. Furthermore, the discharge amount and discharge speed of residual gas can be easily adjusted by adjusting the compression ratio of the compressor or the distance between the ejector and the discharge part, so that it is possible to respond to various situations and provide convenience in use.

[0092] Although the present invention has been described with reference to the embodiments shown in the drawings, this is by way of example only, and those skilled in the art will recognize that various modifications and equivalent alternative embodiments are possible.

[0093] Therefore, the true technical scope of protection of the present invention should be determined by the following claims.

Claims

1. an intake section connected to the exhaust pipe of the HVPE reactor; an exhaust section through which residual gas flowing in from the intake section is exhausted; an injection unit provided in the intake unit to inhale a fluid and inject the fluid in an exhaust direction of the residual gas.

2. 2. The exhaust system of claim 1, wherein the exhaust section includes a Venturi tube.

3. The ejection unit includes a fluid supply unit that supplies the fluid; a compressor that compresses the fluid supplied from the fluid supply unit; 2. The exhaust system of claim 1, further comprising: an ejector connected to the compressor for ejecting the compressed fluid at high speed in the exhaust direction of the residual gas.

4. 4. The exhaust system for an HVPE reactor according to claim 3, wherein the exhaust amount and exhaust speed of the residual gas are adjusted according to the compression ratio of the compressor.

5. 4. The exhaust system for an HVPE reactor according to claim 3, wherein the amount and speed of the residual gas exhausted are adjusted by adjusting the distance between the ejector and the exhaust unit.

6. 4. The exhaust system for an HVPE reactor according to claim 3, wherein the distance between the ejector and the exhaust unit is adjustable by a position adjustment unit that changes the position of the ejector.

7. The position adjustment portion includes a nut portion formed on the suction portion; 7. The exhaust device for an HVPE reactor according to claim 6, further comprising: a bolt portion formed on the ejector to be threadedly coupled to the nut portion.

8. The position adjustment unit includes a slide rail portion formed in the suction unit; a slide member formed on the ejector so as to be slidably coupled to the slide rail portion; 7. The exhaust device for an HVPE reactor according to claim 6, further comprising: a locking portion for fixing the slide member to the slide rail portion.

9. The ejector has a plurality of injection ports connected to the compressor, 4. The exhaust system for an HVPE reactor according to claim 3, further comprising an on-off valve for interrupting the flow of said fluid through said injection port.

10. The injection port includes a main injection port formed in a central portion of the ejector; 10. The exhaust system for an HVPE reactor according to claim 9, further comprising a plurality of auxiliary injection ports provided in a radial direction of the main injection port.

11. 2. The exhaust system of claim 1, wherein a bubbler is provided at the rear end of the exhaust section to prevent the residual gas from flowing back.

12. 10. The exhaust device for an HVPE reactor according to claim 1, wherein a steel wire having a spiral groove is formed on the inner circumferential surface of the exhaust part, thereby improving the exhaust performance of residual gases and fluids.

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