Exhaust device of HVPE reactor

Abstract

The present invention relates to an exhaust device of an HVPE reactor, the exhaust device comprising: a suction unit connected to an HVPE reactor exhaust pipe; an exhaust unit through which residual gas introduced from the suction unit is exhausted; and a spray unit provided in the suction unit and sucking a fluid so as to spray the fluid in the direction in which the residual gas is exhausted.

Description

Exhaust system of HVPE reactor

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

[0002] Hydrogen vapor phase epitaxy (HVPE) is a method that uses ammonia, hydrogen, and various chloride gases as sources to form a compound layer with a relatively thick thickness (tens to hundreds of ㎛) on a substrate.

[0003] HVPE grows gallium nitride (GaN) at a faster rate than metalorganic chemical vapor deposition (MOCVD). It can also be used to grow gallium oxide and indium phosphide thin films.

[0004] Conventional HVPE reactors designed for GaN growth have the problem of parasitic deposition of substances (NH₄Cl, GaCl₃, etc.) near the process gas exhaust port and on the internal surfaces of the reactor near the exhaust port. Ammonia chloride emitted from the exhaust port precipitates at temperatures below approximately 300°C.

[0005] These parasitic deposits (solid compounds) drastically degrade the reactor's performance. To address this issue, a vacuum pump for pressure reduction is used, but clogging of the pump makes it difficult to use. To prevent clogging, a large condensing chamber can be installed upstream of the pump. However, this merely acts as a trap for residual gas and does not effectively address the main issue.

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

[0007] The background technology for the present invention is disclosed in Korean Patent Publication No. 10-2010-0100910 (published on September 15, 2010, title of invention: HVPE reactor device).

[0008] The present invention aims to provide an exhaust device for an HVPE reactor that prevents clogging of the reactor due to parasitic deposition, thereby enabling long-term operation of the reactor.

[0009] The purpose of the present invention is to provide an exhaust device for an HVPE reactor that is easy to control by controlling pressure, thereby easily controlling the exhaust amount and exhaust speed of residual gas.

[0010] An exhaust device of an HVPE reactor according to the present invention may include: a suction portion connected to an exhaust pipe of the HVPE reactor, an exhaust portion through which residual gas introduced from the suction portion is exhausted, and an injection portion provided in the suction portion and sucking a fluid and injecting the fluid in the direction of exhaust of the residual gas.

[0011] The above exhaust section may include a venturi tube.

[0012] The above 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 that is connected to the compressor and ejects the compressed fluid at high speed in the exhaust direction of the residual gas.

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

[0014] The exhaust amount and exhaust speed of the residual gas can be controlled by adjusting the gap between the ejector and the exhaust section.

[0015] The gap between the ejector and the exhaust section can be adjusted by a position adjustment section that changes the position of the ejector.

[0016] The above position adjustment unit may include a nut unit formed in the suction unit and a bolt unit formed in the ejector to be screw-connected to the nut unit.

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

[0018] The above ejector may be formed with a plurality of nozzles connected to the compressor, and may include an opening / closing valve that controls the flow of the fluid through the nozzles.

[0019] The above nozzle may include a main nozzle formed in the central portion of the ejector and a plurality of auxiliary nozzles provided in a radial direction of the main nozzle.

[0020] A bubbler may be provided at the rear end of the above exhaust section to prevent backflow of the residual gas.

[0021] A steel wire formed in a spiral groove is formed on the inner surface of the above exhaust section, so that the exhaust performance of residual gas and fluid can be improved.

[0022] According to the exhaust device of the HVPE reactor according to the present invention, clogging of the reactor due to parasitic deposition can be prevented, thereby enabling long-term operation of the reactor.

[0023] The present invention can easily control the exhaust amount and exhaust speed of residual gas by adjusting the compression ratio of the compressor or the gap between the ejector and the exhaust section, thereby enabling response according to the situation and providing convenience in use.

[0024] The present invention has a simple structure of an intake section, an injection section, and an exhaust section, so that manufacturing costs are low and weight reduction is possible.

[0025] FIG. 1 is a schematic diagram illustrating an HVPE reactor according to one embodiment of the present invention.

[0026] FIG. 2 is a drawing illustrating an exhaust device of an HVPE reactor according to one embodiment of the present invention.

[0027] FIG. 3 is a drawing for explaining an exhaust device injection unit of an HVPE reactor according to one embodiment of the present invention.

[0028] Figure 4 is a cross-sectional view taken along line AA of Figure 2.

[0029] FIG. 5 is a drawing for explaining a first modified example of an exhaust device of an HVPE reactor according to one embodiment of the present invention.

[0030] Figure 6 is a cross-sectional view taken along line AA of Figure 5.

[0031] FIG. 7 is a drawing for explaining a second modified example of an exhaust device of an HVPE reactor according to one embodiment of the present invention.

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

[0033] In this process, the thickness of lines and the sizes of components depicted in the drawings may be exaggerated for clarity and convenience. The terms described below are defined based on their functions in the present invention and may vary depending on the intent or custom of the user or operator. Therefore, the definitions of these terms should be based on the overall content of this specification.

[0034] In this specification, when it is said that a part is "connected (or connected)" to another part, this includes not only cases where it is "directly connected (or connected)" but also cases where it is "indirectly connected (or connected)" with another member in between. In this specification, when it is said that a part "includes (or comprises)" a certain component, this does not mean that other components are excluded, but rather that it may "include (or comprise)" other components, unless specifically stated otherwise.

[0035] Throughout this specification, the same reference numerals may refer to the same components. Even if the same or similar reference numerals are not mentioned or described in a specific drawing, they may be described based on other drawings. Even if a part is not indicated by a reference numeral in a specific drawing, that part may be described based on other drawings. The number, shape, size, and relative size differences of detailed components included in the drawings of this application are set for the convenience of understanding, and do not limit the embodiments and may be implemented in various forms.

[0036] FIG. 1 is a schematic drawing of an HVPE reactor according to one embodiment of the present invention, FIG. 2 is a drawing illustrating an exhaust device of an HVPE reactor according to one embodiment of the present invention, FIG. 3 is a drawing for explaining an exhaust device injection unit of an HVPE reactor according to one embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line AA of FIG. 3.

[0037] First, referring to Fig. 1, the HVPE reactor (1) can be divided into a reaction section (10) and an exhaust device (100). The reaction section (10) is divided into a source section (A) where gas is supplied and a growth section (B) where a subtractor (14) is located, and all internal components are composed of quartz tubes.

[0038] The source area (A) is formed in a tubular shape, and an HCI gas supply pipe (11) for supplying HCI gas is connected thereto, a source boat (12) is arranged, and gallium (Ga) metal, which is a precursor, is positioned in the source boat (12).

[0039] A carrier gas supply pipe (13) for introducing carrier gas is connected to the source area (A), and the discharge portion on the downstream side of the source area (A) that discharges GaCl gas is tapered.

[0040] The growth zone (B) is the zone where the actual reaction for growing gallium oxide occurs, and a substrate (14) equipped with a target substrate is located there. A substrate (e.g., sapphire, SiC) is used for homo-epitaxial growth.

[0041] The substrate is fixed to the load and connected to a motor so that it can be rotated during the process.

[0042] Doping gas is injected to control and transport carrier concentration during thin film growth.

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

[0044] 2HCl + 2Ga → 2GaCl + H₂

[0045] Gallium chloride formed in this way is transported from the source tube to the substrate section by carrier gas supplied from the carrier gas supply pipe (13).

[0046] When ammonia (NH₃) gas is supplied from an ammonia supply pipe (15) into the reaction section (10), the two gases are adsorbed on a substrate (e.g., sapphire, SiC) in a quartz tube heated to 900 to 1,100°C, thermally decompose, and combine 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 ammonia chloride (NH₄Cl) and gallium chloride (GaCl₃). This ammonia chloride and gallium chloride are discharged through the exhaust pipe (16) together with a carrier gas such as hydrogen or nitrogen.

[0049] That is, the chemical residual gases that did not participate in the formation of a thin film by thermal decomposition must be discharged to the outside, and at this time, since the residues due to this residual gas become parasitic around the exhaust pipe (16), they must be quickly discharged out of the reactor.

[0050] The exhaust device (100) of the HVPE reactor (1) according to one embodiment of the present invention can function as a configuration capable of quickly discharging residual gas as described above, thereby preventing clogging of the exhaust pipe (16).

[0051] Referring to FIGS. 1 to 4, an exhaust device (100) of 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 (130).

[0052] The suction part (110) is connected to the exhaust pipe (16) of the HVPE reactor (1). The suction part (110) can be directly connected to the end of the exhaust pipe (16).

[0053] As illustrated in Fig. 2, the exhaust section (120) is configured to exhaust residual gas introduced from the intake section (110), and can function as a passage configuration that discharges residual gas introduced into the intake section (110) to the outside.

[0054] This exhaust section (120) may be formed as a venturi tube (125). That is, it may be formed as a tube in which the thickness of the exhaust section (120) passage gradually narrows and then widens again, and due to this structural feature, the velocity of the residual gas passing through the exhaust section (120) and the fluid of the injection section (130) described later can be accurately measured.

[0055] As illustrated in Fig. 4, a spiral groove-shaped steel wire (127) is formed on the inner surface of the exhaust section (120), thereby improving the exhaust performance of residual gas and fluid. The residual gas and fluid exhausted through the exhaust section (120) by the steel wire (127) can form a vortex, thereby improving the exhaust performance.

[0056] The injection unit (130) is provided in the suction unit (110) and sucks in fluid and injects the fluid in the direction of exhaust of the residual gas. By injecting the fluid at a high speed to generate a pressure difference, the injection unit can function as a configuration that sucks in the residual gas in the exhaust pipe (16) into the suction unit (110) and discharges it smoothly.

[0057] For example, the injection unit (130) may include a fluid supply unit (132) that supplies 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 ejects the compressed fluid at high speed in the direction of exhausting residual gas.

[0058] The fluid supply unit (132) may be formed of a tank in which fluid is stored, and the fluid may include steam, water, or gas.

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

[0060] The ejector (135) is coupled to the suction part (110) and is positioned so that the fluid injection direction is directed toward the exhaust part (120), and the fluid delivered through the compressor (134) is injected at high speed.

[0061] When the fluid is injected at high speed through the ejector (135), the pressure at the outlet side of the ejector (135) is lowered, and due to this pressure difference, the residual gas discharged through the exhaust pipe (16) of the HVPE reactor (1) connected to the suction part (110) is sucked into the suction part (110).

[0062] The residual gas sucked in this way is mixed with the fluid within the suction portion (110), and the residual gas and fluid flow to the exhaust portion (120), whereby velocity energy is converted into pressure energy, thereby allowing the residual gas and 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 performance degradation of the reactor (1) can be prevented.

[0064] The exhaust device (100) of the HVPE reactor according to the present embodiment can control the exhaust amount and exhaust speed of the residual gas.

[0065] This allows the exhaust amount and exhaust speed of the residual gas to be controlled according to the compression ratio of the compressor (134). That is, by controlling the compression ratio of the compressor (134) to control the outlet pressure of the ejector (135), the exhaust amount and exhaust speed of the residual gas can be controlled.

[0066] As shown in Fig. 3, the exhaust amount and exhaust speed of the residual gas can be controlled by adjusting the gap between the ejector (135) and the exhaust part (120).

[0067] In more detail, the gap (d) between the ejector (135) and the exhaust portion (120) can be adjusted by a position adjustment portion (140) that varies the position of the ejector (135). For example, the position adjustment portion (140) may include a nut portion (142) formed on the suction portion (110) and a bolt portion (144) formed on the ejector (135) to be screw-connected to the nut portion (142).

[0068] The ejector (135) and the suction part (110) are screw-connected by the bolt part (144) and the nut part (142), so that the distance between the inlet side of the exhaust part (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 part (110) and the ejector (135), but it is not limited to this, and various design changes that can change the position of the ejector (135) are possible.

[0070] A bubbler (150) that prevents backflow of residual gas may be provided at the rear end of the exhaust section (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) may function as a configuration for exhausting residual gas in other situations where the exhaust device (100) is not used during the purification of the reactor (1).

[0072] Aqueous ammonia solutions and other wastes can be very harmful to the reactor (1) section, and the vapor backflow of these solutions during low process gas flow can adversely affect the growth process, which can be prevented by the bubbler (150).

[0073] Water may be used as the dissolution fluid in the tank (160). In this embodiment, water is used as the dissolution fluid, but the present invention is not limited thereto, and 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 more efficiently dissolved by some other alcohols than by water.

[0074] FIG. 5 is a drawing showing a first modified example of an exhaust device (100) of an HVPE reactor according to one embodiment of the present invention, and FIG. 6 is a drawing showing BB of FIG. 5.

[0075] Referring to FIGS. 5 and 6, the ejector (235) may be formed with a plurality of injection holes (236) connected to the compressor (134).

[0076] The nozzle (236) may include a main nozzle (237) formed in the center of the ejector (235) and a plurality of auxiliary nozzles (238) provided in a radial direction of the main nozzle (237).

[0077] At this time, 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 when injection is made through the main injection port (237), outside air may be introduced through the auxiliary injection port (238).

[0078] For example, the exhaust amount and exhaust speed of the residual gas may vary depending on the number of injection holes (236) formed in the ejector (235).

[0079] A plurality of nozzles (236) may be provided with an on-off valve (v) for controlling the flow of fluid. A plurality of on-off valves (v) may be provided to open and close each nozzle (136).

[0080] The amount and speed of exhaust of residual gas can be controlled by interrupting the fluid flow by these opening / closing valves (v).

[0081] The ejector (235) is slidably connected to the suction part (110), and the gap between the ejector (235) and the exhaust part (120) can be adjusted by a position adjustment part (140) that changes the position of the ejector (135).

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

[0083] The slide rail portion (242) extends to the upper portion of the suction portion (110) and is formed to face each other, and the slide member (244) is formed to protrude on both sides of the ejector (235) and is connected to the slide rail portion (242) so as to slide and move, and the locking portion (246) may include a screw thread (247) formed on the outer side of the slide rail portion (242) and a locking nut portion (248) screw-connected to the screw thread (247).

[0084] The locking member (246) can be changed into various forms that can fix the slide member (244) to a specific position, and this is nothing more than a simple design change.

[0085] FIG. 7 is a drawing for explaining a second modified example of an exhaust device (100) of an HVPE reactor according to one embodiment of the present invention.

[0086] Referring to Fig. 7, the suction part (110) and the exhaust part (120) are directly connected and extend in the same line. That is, the exhaust pipe (16), suction part (110), and exhaust part (120) of the reactor (1) extend in the same line, enabling smoother exhaust of residual gas.

[0087] The ejector (335) extends inwardly through the suction portion (110), and can be formed so that the spraying direction of the ejector (335) is bent toward the exhaust portion (120).

[0088] Accordingly, the injection port (336) of the ejector (135) is located at the center of the suction portion (110), and when the fluid delivered through the compressor (134) is injected at high speed, the pressure at the outlet side of the injection port (336) of the ejector (335) is lowered, so that the residual gas discharged through the exhaust pipe (16) is sucked into the suction portion (110) and smoothly exhausted through the exhaust portion (120).

[0089] The ejector (335) is slidably connected to the suction part (110), and the gap between the ejector (335) and the exhaust part (120) can be adjusted by a position adjustment part (240) that changes the position of the ejector (335).

[0090] The position adjustment unit (240) according to the second modified example can move the ejector (135) in a horizontal direction, and has the same structure as the first modified example, so a detailed description thereof will be replaced with the above. The amount and speed of the exhaust of the residual gas can also be controlled by adjusting the gap between the ejector (335) and the exhaust unit (120) using the position adjustment unit (240).

[0091] According to the present invention described above, the residual gas generated in the reactor can be smoothly discharged, thereby preventing clogging of the reactor due to parasitic deposition, thereby enabling long-term operation of the reactor. In addition, the exhaust amount and exhaust speed of the residual gas can be easily controlled by adjusting the compression ratio of the compressor or the gap between the ejector and the exhaust section, thereby enabling response according to the situation and providing convenience in use.

[0092] Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom.

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

Claims

1. Suction port connected to the HVPE reactor exhaust pipe; An exhaust section through which residual gas drawn in from the above suction section is exhausted; and An exhaust device for an HVPE reactor, characterized by including an injection unit provided in the suction unit and sucking in a fluid and injecting the fluid in the exhaust direction of the residual gas.

2. In paragraph 1, An exhaust device of an HVPE reactor, characterized in that the exhaust section includes a venturi tube.

3. In paragraph 1, The above injection unit includes a fluid supply unit that supplies the fluid; A compressor that compresses the fluid supplied from the fluid supply unit; and An exhaust device for an HVPE reactor, characterized by including an ejector connected to the compressor and ejecting the compressed fluid at high speed in the exhaust direction of the residual gas.

4. In paragraph 3, An exhaust device of an HVPE reactor, characterized in that the exhaust amount and exhaust speed of the residual gas are controlled according to the compression ratio of the compressor.

5. In paragraph 3, An exhaust device for an HVPE reactor, characterized in that the exhaust amount and exhaust speed of the residual gas are controlled by adjusting the gap between the ejector and the exhaust section.

6. In paragraph 3, An exhaust device for an HVPE reactor, characterized in that the gap between the ejector and the exhaust section is adjustable by a position adjustment section that changes the position of the ejector.

7. In paragraph 6, The above position adjustment part is a nut part formed in the suction part; and An exhaust device for an HVPE reactor, characterized in that it includes a bolt portion formed on the ejector so as to be screw-connected to the nut portion.

8. In paragraph 6, The above position adjustment part is a slide rail part formed in the suction part; A slide member formed on the ejector so as to be movably connected to the slide rail section; and An exhaust device for an HVPE reactor, characterized in that it includes a locking part that fixes the slide member to the slide rail part.

9. In paragraph 3, The above ejector is formed with a plurality of nozzles connected to the compressor, An exhaust device of an HVPE reactor, characterized in that it includes an on-off valve for controlling the flow of the fluid through the nozzle.

10. In paragraph 9, The above nozzle is a main nozzle formed in the central portion of the ejector; and An exhaust device of an HVPE reactor, characterized in that it includes a plurality of auxiliary injection ports provided in a radial direction of the main injection port.

11. In paragraph 1, An exhaust device for an HVPE reactor, characterized in that a bubbler is provided at the rear end of the exhaust section to prevent backflow of the residual gas.

12. In paragraph 1, An exhaust device for an HVPE reactor, characterized in that a steel wire formed in a spiral groove is formed on the inner surface of the exhaust section, thereby improving the exhaust performance of residual gas and fluid.

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