JP4864057B2 - Vapor growth apparatus and vapor growth method - Google Patents

Description

  The present invention relates to a vapor phase growth comprising a shower plate disposed to face a substrate holding member for placing a substrate to be processed in a reaction furnace and provided to supply gas toward the substrate to be processed. The present invention relates to an apparatus and a vapor phase growth method.

Conventionally, in the manufacture of light emitting diodes and semiconductor lasers, organometallic gases such as trimethylgallium (TMG) or trimethylaluminum (TMA), and ammonia (NH ₃ ), phosphine (PH ₃ ), arsine (AsH ₃ ), etc. An MOCVD (Metal Organic Chemical Vapor Deposition) method and an MOCVD apparatus are used in which a hydrogen compound gas is introduced into a growth chamber as a source gas contributing to film formation to grow a compound semiconductor crystal.

  The MOCVD method is a method for growing a compound semiconductor crystal on a substrate to be processed by introducing the source gas together with an inert gas into a growth chamber and heating it to cause a gas phase reaction on the substrate to be processed. is there. In the production of compound semiconductor crystals using MOCVD, there is always a high demand for how to secure the maximum yield and production capacity while reducing costs while improving the quality of growing compound semiconductor crystals. Has been.

  FIG. 11 shows a schematic configuration of an example of a conventional vertical shower head type MOCVD apparatus used in the MOCVD method. In this MOCVD apparatus, a gas pipe 93 for introducing a reaction gas and an inert gas from a gas supply source 92 to a growth chamber inside the reaction furnace 91 is connected, and a growth chamber 81 inside the reaction furnace 91 is connected. A shower plate 90 having a plurality of gas discharge holes for introducing a reaction gas and an inert gas into the growth chamber is installed as a gas introduction part. In addition, a rotary shaft 82 that is rotatable by an actuator (not shown) is installed in the center of the growth chamber 81 of the reaction furnace 91, and a susceptor 98 is provided at the tip of the rotary shaft 82 so as to face the shower plate 90. A heater 99 for heating the susceptor 98 is attached to the lower part of the susceptor 98. A gas exhaust part 94 for exhausting the gas in the growth chamber 81 inside the reaction furnace 91 to the outside is installed at the lower part of the reaction furnace 91, and the gas exhaust part 94 is connected via a purge line 95. The exhaust gas treatment device 96 for detoxifying the exhausted gas is connected.

  In the vertical showerhead type MOCVD apparatus having the above-described configuration, the substrate 97 is placed on the susceptor 98 when the compound semiconductor crystal is grown, and then the susceptor 98 is rotated by the rotation of the rotating shaft 82. Then, the substrate 97 is heated to a predetermined temperature through the susceptor 98 by the heating of the heater 99, and the reaction gas and non-reactant gas are supplied from the plurality of gas discharge holes formed in the shower plate 90 to the growth chamber 81 inside the reaction furnace 91. An active gas is introduced.

  As a method of forming a thin film by supplying a plurality of reaction gases and reacting them on a substrate to be processed, conventionally, a plurality of gases are mixed in a shower head, and are covered from gas discharge ports provided in a large number on the shower plate. A method has been adopted in which a reactive gas is blown out onto a processing substrate. However, according to the above method, a gas phase reaction of the gas mixed in the shower head occurs, which causes a problem that the inside of the shower plate is contaminated or clogged.

  In order to solve this problem, Japanese Patent Laid-Open No. 5-144453 (Patent Document 1) provides a rectifying plate having many through holes at a gas introduction port, and separately passes a plurality of types of gases through these through holes. A method is shown in which source gases are separately blown downward from a current plate. Since the reaction gas is supplied in a separated state, no gas phase reaction occurs in the shower head.

  As another method, in Japanese Patent Laid-Open No. 5-152208 (Patent Document 2), a buffer area is provided for each of a plurality of supply gases, and each reaction gas is separated from the buffer area through a gas discharge hole of a shower plate. A method of supplying to the growth chamber in the state is shown. Since the reaction gas is supplied in a separated state, no gas phase reaction occurs in the shower head.

  When a desired thin film is formed on a substrate to be processed by the MOCVD method, it is known that the surface reaction caused on the surface of the substrate to be processed by the reactive source gas has an extremely complicated mechanism. That is, since a number of parameters such as the temperature of the substrate to be processed, the temperature of the source gas, the flow rate, the pressure, the type of active chemical species contained in the source gas, and the residual gas components in the reaction system contribute to the surface reaction, MOCVD It is extremely difficult to form a desired thin film by controlling these parameters by a method. The above prior art involves mixing the reaction gas far away from the substrate to be processed, reacting before the reaction gas reaches the substrate to be processed, making it difficult to control the surface reaction of the substrate to be processed, It may cause quality degradation.

  In order to solve this problem, Japanese Patent Application Laid-Open No. 8-91989 (Patent Document 3) supplies a plurality of reaction gases to a growth chamber in a state of being separated by individual shower plate conduits, and cools each shower plate conduit. A method is shown in which a cooling chamber is provided on the growth chamber side. Since the surface of the shower plate can be cooled by the cooling chamber, the distance between the shower head and the substrate to be processed can be reduced, and a gas phase reaction can occur at a position close to the heated substrate to be processed. Thus, the controllability of the surface reaction of the substrate to be processed and the raw material utilization efficiency can be improved.

  In JP 2006-216830 A (Patent Document 4), a gas introduction port and a gas distribution space are provided in the upper part of the gas supply part of the disc body, and a plurality of gas injection ports are provided in the entire area on the lower surface. A gas passage that communicates the distribution space and the gas outlet is provided in parallel with the axis Y of the substrate holder, a refrigerant jacket is formed on the outer periphery of the disc body, and a refrigerant collecting passage that extends in the radial direction from the center of the disc body is provided. The refrigerant passage communicating from the refrigerant jacket to the refrigerant collecting passage is arranged in the upper and lower stages and the gas passage is cooled from the four sides. Since the gas passage is cooled from the four sides by the refrigerant passage, the source gas and the carrier gas are sufficiently cooled. Various source gases ejected from the gas outlet are supplied onto the substrate holder, preventing the source gases from mixing with each other before reaching the substrate and preventing the formation of additional compounds, improving the efficiency of raw material utilization, Quality degradation can be prevented.

A first shower plate disposed to face a substrate holding member for placing the substrate to be processed in the reaction furnace and provided to supply the first gas toward the substrate to be processed; There is known a vapor phase growth apparatus including a second shower plate that is disposed on the opposite side of the substrate holding member with respect to the shower plate and is provided to supply the second gas toward the substrate to be processed ( Patent Document 5 and Patent Document 6).
Japanese Patent Laid-Open No. 5-144453 (published on June 11, 1993) Japanese Patent Laid-Open No. 5-152208 (published on June 18, 1993) Japanese Laid-Open Patent Publication No. 8-91989 (Patent No. 3444236) (published on April 9, 1996) Japanese Laid-Open Patent Publication No. 2006-216830 (released on August 17, 2006) JP 2000-144432 A (published May 26, 2000) JP 2004-158499 A (published June 3, 2004)

  In order to grow a thin film having a uniform film thickness distribution on a substrate to be processed with good reproducibility, it is necessary to cause a reaction gas to react in a gas phase with a uniform concentration distribution on the substrate. In addition, it is necessary to prevent source gases from being mixed with each other before reaching the substrate and to generate an additive compound, and to improve the controllability of the surface reaction of the substrate to be processed and the utilization efficiency of the raw material.

  If the reaction gas is supplied to the growth chamber in a state of being separated as in Patent Documents 1 and 2, a gas phase reaction will not occur in the shower head, but it involves mixing the reaction gas far away from the substrate to be processed. The reaction gas reacts before reaching the substrate to be processed, which makes it difficult to control the surface reaction of the substrate to be processed, resulting in a deterioration in the quality of the growth film.

  In Patent Document 3, since the surface of the shower plate can be cooled by the cooling chamber, the distance between the shower head and the substrate to be processed can be reduced, and at a position close to the heated substrate to be processed. A gas phase reaction can be caused, and the controllability of the substrate surface reaction and the raw material utilization efficiency can be improved. However, in the shower head structure of Patent Document 3, the outlet of each reactive gas is separated and mixed after being introduced into the growth chamber. As the distance between the head and the substrate to be processed becomes smaller, the mixed region is not sufficient, and the concentration distribution may occur in the source gas. Therefore, there are problems that a film thickness distribution and a composition distribution may occur in the growth film on the substrate to be processed, and that there is a limit to the improvement of raw material utilization efficiency.

  In Patent Document 4, since the gas passage is cooled from the four sides, the distance between the shower head and the substrate to be processed can be reduced, and a gas phase reaction is caused at a position close to the heated substrate to be processed. It is possible to improve the controllability of the substrate surface reaction and the raw material utilization efficiency. However, in the shower head structure of Patent Document 4, the carrier gas can be supplied in a shower shape over almost the entire surface, but each source gas and dopant gas are supplied linearly from the spacer block in the radial direction. Will do. There is a limit to the mixing property of each gas. In particular, as the distance between the shower head and the substrate to be processed becomes smaller, the mixing region is not sufficient, and the concentration distribution may occur in the source gas. Therefore, there are problems that a film thickness distribution and a composition distribution may occur in the growth film on the substrate to be processed, and that there is a limit to the improvement of raw material utilization efficiency.

  In the configurations described in Patent Document 5 and Patent Document 6, in order to adjust the volume of the mixing chamber formed by the tip of the gas conduit and the gas flow path and in which the first gas and the second gas are mixed, There is a need to re-manufacture each main body of the second shower plate provided with the conduit, and there is a problem that the work is complicated and the cost increases.

  In the configuration described in Patent Document 5, it is necessary to attach and detach the gas conduit from the opposite side of the growth chamber. However, if the gas conduit is attached and detached from the opposite side of the growth chamber, there is a problem that maintenance becomes difficult. The growth chamber may be opened by normal maintenance, but the gas distribution space on the opposite side basically has no opportunity to open, so it is necessary to open the gas conduit from the gas distribution space side. This causes a problem that the operating rate is lowered. In addition, when attempting to attach or detach the gas conduit from the gas distribution space side, a problem arises in that turbulence occurs because the nozzle protrudes into the gas supply chamber.

  In view of the above circumstances, the object of the present invention is to prevent the addition compound from being generated before reaching the substrate, improve the mixing property of the reaction gas supplied from the shower plate to the growth chamber, and improve the gas on the substrate surface to be processed. It is possible to make the concentration distribution uniform, improve the controllability of the surface reaction of the substrate to be processed, that is, improve the film thickness and composition ratio, and improve the raw material utilization efficiency and the vapor phase growth apparatus and gas It is to provide a phase growth method.

  A vapor phase growth apparatus according to the present invention includes a first shower plate that is disposed to face a substrate holding member on which a substrate to be processed in a reaction furnace is placed and supplies a first gas toward the substrate to be processed. A vapor phase growth apparatus comprising: a second shower plate disposed on an opposite side of the substrate holding member with respect to the first shower plate and supplying a second gas toward the substrate to be processed; A gas flow path through which the first gas flows toward the substrate to be processed is formed in one shower plate, and the second shower plate protrudes from the second shower plate and enters the gas flow path. A gas conduit that is inserted and flows the second gas toward the substrate to be processed is provided, and the gas conduit is detachably provided on the second shower plate.

  With this feature, since the gas conduit is detachably provided on the second shower plate, the gas conduit can be detached from the second shower plate, and the size of the mixing chamber can be increased by changing the length of the gas conduit. It is possible to change. Since the gas conduit can be removed, it is possible to adjust the size of the mixing chamber only by changing the gas conduit that becomes the flow path of the second gas without having to remanufacture the main body. The apparatus can cope with the film formation.

  In the vapor phase growth apparatus according to the present invention, it is preferable that a plurality of holes are formed at the outlet of the gas conduit.

  According to the above configuration, by providing a plurality of holes at the outlet of the gas conduit serving as the flow path for the second gas, it is possible to further expand the ejection of the second gas. Therefore, the mixing of the first gas and the second gas is improved, the gas concentration distribution on the surface of the substrate to be processed can be made uniform, and the surface reaction of the substrate to be processed can be controlled. In other words, the film forming thickness and composition ratio can be improved, and the raw material utilization efficiency can be improved.

  In the vapor phase growth apparatus according to the present invention, a first gas distribution space for supplying the first gas to the gas flow path is formed between the first shower plate and the second shower plate, and the second shower The plate is preferably detachably provided from the first shower plate so that the first gas distribution space is exposed.

  According to the above configuration, since the first gas distribution space can be exposed, the maintainability is improved, especially when an additive compound is generated inside the shower plate or when foreign matter is mixed. The cleanability is greatly improved, and internal contamination can be completely removed (according to the conventional structure, it is impossible to completely clean the inside because it is joined by brazing or the like. The hole is small (φ0. 6 mm), since the cleaning liquid is difficult to flow sufficiently and stagnation can occur, there is a high possibility that foreign matter will accumulate.

  In the vapor phase growth apparatus according to the present invention, the second shower plate includes a base and a cover plate, a second gas distribution space is formed between the base and the cover plate, and the cover plate includes: It is preferable that the second gas distribution space is provided so as to be removable from the base so that the second gas distribution space is exposed.

  According to the above configuration, since the second gas distribution space can be exposed, maintenance is improved, especially when an additive compound is generated inside the shower plate or when foreign matter is mixed. Cleanability is dramatically improved and internal contamination can be completely removed.

  In the vapor phase growth apparatus according to the present invention, it is preferable that a refrigerant flow path for flowing a refrigerant for adjusting the temperature of the gas conduit is formed in the second shower plate.

  According to the above configuration, the refrigerant flow path for adjusting the temperature of the second gas flow path is configured, so that the temperature of the second gas flow path can be varied and the second gas temperature can be controlled. It becomes. That is, the temperature of the first gas and the second gas can be individually adjusted. Thereby, the controllability of the surface reaction of the substrate to be processed can be improved, that is, the film formation thickness and the composition ratio can be improved, and the raw material utilization efficiency can be improved.

  In the vapor phase growth apparatus according to the present invention, it is preferable that the first gas includes a group III gas and the second gas includes a group V gas.

  According to the above configuration, the outlet of the gas conduit serving as the flow path for the second gas has a structure in which the temperature rises more easily than the first gas flow path that directly receives heat from the heater and is temperature-controlled by the refrigerant flow path. is there. An organic gas is used as the group V gas, and unless the temperature is raised, molecules are decomposed and are not doped into the growth film, or are doped as molecules to form holes, leading to deterioration of film quality and growth rate. Therefore, by setting the gas conduit serving as the flow path of the second gas to be a group V gas, the substrate temperature is heated in advance outside the reaction chamber and the activated gas is supplied to the reaction chamber, whereby the substrate temperature is increased to the group III system. The gas phase reaction can be allowed to proceed while maintaining a temperature at which the gas is not thermally decomposed.

  In the vapor phase growth apparatus according to the present invention, it is preferable to provide an elevating mechanism for moving the gas conduit and the gas flow path relatively up and down along the longitudinal direction of the gas conduit.

  According to the above configuration, the size of the mixing chamber of the first gas and the second gas can be varied, the raw material gas mixing property is improved, and the gas concentration distribution on the surface of the substrate to be processed is made uniform. Thus, the controllability of the surface reaction of the substrate to be processed can be improved, that is, the film formation thickness and the composition ratio can be improved, and the raw material utilization efficiency can be improved. In addition, the size of the mixing chamber can be varied during film formation, and even when growing a plurality of films in which the reaction gas flow rate and the substrate temperature to be processed are grown in one film formation, Since the optimum size of the mixing chamber can be set, an optimum single film can be laminated, and a high-quality multilayer film can be formed.

  Furthermore, the degree of protrusion of the gas conduit from the flow path, the distance from the tip of the gas conduit to the substrate to be processed, and the distance from the first flow path outlet can be changed by moving the relative position, so the film quality and growth rate can be changed. It becomes.

  In the vapor phase growth apparatus according to the present invention, it is preferable that the lifting mechanism relatively lifts and lowers the first shower plate and the second shower plate along the longitudinal direction of the gas conduit.

  According to the above configuration, the size of the mixing chamber of the first gas and the second gas can be varied with a simple configuration.

  In the vapor phase growth apparatus according to the present invention, it is preferable that the lifting mechanism relatively lifts and lowers the gas conduit and the second shower plate along the longitudinal direction of the gas conduit.

  According to the above configuration, the size of the mixing chamber of the first gas and the second gas can be varied with a simple configuration.

  In the vapor phase growth apparatus according to the present invention, the gas conduit has a flange fitted to the second shower plate, and the outer diameter of the flange of the gas conduit is smaller than the inner diameter of the gas flow path. Is preferred.

  According to the above configuration, the gas conduit can be exchanged from the reaction furnace side.

  In the vapor phase growth apparatus according to the present invention, it is preferable that a groove or a protrusion to be fitted to the exchange jig of the gas conduit is formed at the tip of the gas conduit.

  According to the above configuration, the gas conduit can be easily rotated and replaced.

  In the vapor phase growth apparatus according to the present invention, the first shower plate is formed by an inner wall of the gas flow path in front of the tip of the gas conduit and mixes the first gas and the second gas. It is preferable to have.

  According to the above configuration, the mixing chamber improves the raw material gas mixing property, makes it possible to make the gas concentration distribution on the surface of the substrate to be processed uniform, and improves the controllability of the surface reaction of the substrate to be processed. While improving a film thickness and a composition ratio, raw material utilization efficiency can be improved.

  The vapor phase growth method according to the present invention is a first shower plate disposed facing a substrate holding member on which a substrate to be processed in a reaction furnace is placed, and the first gas is directed toward the substrate to be processed. A first shower plate formed with a flowing gas flow path supplies a first gas toward the substrate to be processed, and a second shower disposed on the opposite side of the substrate holding member with respect to the first shower plate. A second shower plate having a gas conduit that protrudes from the second shower plate and is inserted into the gas flow path to flow the second gas toward the substrate to be processed; In the vapor phase growth method of supplying the second gas toward the second gas, the gas conduit is detachably provided on the second shower plate.

  With this feature, since the gas conduit is detachably provided on the second shower plate, the gas conduit can be detached from the second shower plate, and the size of the mixing chamber can be increased by changing the length of the gas conduit. It is possible to change. Since the gas conduit can be removed, it is possible to adjust the size of the mixing chamber only by changing the gas conduit that becomes the flow path of the second gas without having to remanufacture the main body. It can be a method corresponding to the film formation.

  In the vapor phase growth apparatus according to the present invention, as described above, since the gas conduit is detachably provided on the second shower plate, it becomes a flow path for the second gas without the need to remanufacture the main body. It is possible to adjust the size of the mixing chamber only by changing the gas conduit, and there is an effect that the apparatus can be adapted to film formation under various conditions.

  In the vapor phase growth method according to the present invention, as described above, since the gas conduit is detachably provided on the second shower plate, there is no need to remanufacture the main body and it becomes a flow path for the second gas. It is possible to adjust the size of the mixing chamber only by changing the gas conduit, and there is an effect that the apparatus can be adapted to film formation under various conditions.

  An embodiment of the present invention will be described below with reference to FIGS.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing a configuration of a vapor phase growth apparatus 1 according to the first embodiment. The vapor phase growth apparatus 1 is constituted by a vertical shower head type MOCVD apparatus. The vapor phase growth apparatus 1 includes a reaction furnace 14. In the reaction furnace 14, a disk-shaped substrate holding member 16 on which the substrate to be processed 15 is placed is provided. A shaft-like rotation transmission member 20 is coupled to the lower side of the substrate holding member 16, and the substrate is held so as to be rotatable around the rotation transmission member 20 perpendicular to the surface of the substrate to be processed 15 by a drive mechanism (not shown). A member 16 is provided. A heater 17 that heats the substrate holding member 16 is further provided below the substrate holding member 16.

  A gas supply portion 18 having a substantially cylindrical shape is provided on the upper side of the reaction furnace 14. The gas supply unit 18 includes a shower plate 2 and a shower plate 3. The shower plate 2 is disposed to face the substrate holding member 16 on which the substrate 15 to be processed in the reaction furnace 14 is placed, and is provided to supply the first gas toward the substrate 15 to be processed. The shower plate 3 is disposed on the opposite side of the substrate holding member 16 with respect to the shower plate 2 and is provided to supply the second gas toward the substrate 15 to be processed.

  FIG. 2 is a cross-sectional view showing a detailed structure of the gas supply unit 18 provided in the vapor phase growth apparatus 1, and FIG. 3 is an enlarged cross-sectional view of a part A shown in FIG. FIG. 4 is a plan view of the gas supply unit 18 provided in the vapor phase growth apparatus 1 as viewed from the substrate to be processed 15 side.

  In the shower plate 2, a plurality of gas flow paths 4 a through which the first gas flows toward the substrate to be processed 15 are formed at predetermined intervals. The shower plate 2 has a wall surface 26 that faces the substrate holding member 16, and a channel outlet 25 of each gas channel 4 a is formed on the wall surface 26. A reaction chamber 19 is formed by the wall surface 26 and the inner wall of the reaction furnace 14. A gas discharge port 21 is formed at a position lower than the substrate holding member 16 on the side wall of the reaction furnace 14. An O-ring 22 a for sealing the reaction chamber 19 is provided between the reaction furnace 14 and the shower plate 2.

  A gas distribution space 9 is formed between the shower plate 2 and the shower plate 3 in order to supply the first gas to the gas flow path 4a. The shower plate 3 is detachable from the shower plate 2 so that the gas distribution space 9 is exposed. Between the shower plate 2 and the shower plate 3, an O-ring 22b for sealing the gas distribution space 9 is provided. A plurality of gas inlets 23 for supplying the first gas to the gas distribution space 9 are provided at the periphery of the shower plate 2.

  The shower plate 3 has a plurality of gas conduits 5 provided to flow the second gas toward the substrate 15 to be processed, protruding from the shower plate 3 and inserted into the gas flow paths 4a. A gas flow path 4 b through which the second gas flows is formed in the gas conduit 5.

  The shower plate 3 has a base 7 and an upper plate 8. A gas distribution space 10 is formed between the base 7 and the upper plate 8. The upper plate 8 is detachably provided from the base 7 so that the gas distribution space 10 is exposed. An O-ring 22 c for sealing the gas distribution space 10 is provided between the base 7 and the upper plate 8. The upper plate 8 is formed with a second gas introduction port 24 for supplying the second gas to the gas distribution space 10.

  In the shower plate 2, a refrigerant flow path 11 for flowing a refrigerant for adjusting the temperature of the gas conduit 5 is formed around the gas flow path 4a.

  In the shower plate 2, a mixing chamber 12 in which the first gas and the second gas are mixed is formed by the inner wall of the gas flow path 4 a in front of the tip of the gas conduit 5.

  The shower plate 2 includes a lower plate 29 provided facing the substrate holding member 16, an upper plate 28 provided on the opposite side of the substrate holding member 16 at a predetermined interval from the lower plate 29, and a lower plate 29. And a gas conduit 30 provided through the upper plate 28 to form the gas flow path 4a.

  The shower plate 2 is provided with a flange portion 32 in which a first gas introduction port 23 for introducing the first gas and an introduction path 31 for guiding the first gas to the gas distribution space 9 are formed. The base 7 and the upper plate 8 are fixed to the flange portion 32 with fixing screws 39 at the periphery.

  The refrigerant flow path 11 is provided with a refrigerant adjustment ring 33 for evenly supplying the refrigerant around each gas flow path 4a. The gas distribution space 9 is provided with a first gas adjustment ring 36 for uniformly supplying the first gas to the gas flow paths 4a. The gas distribution space 10 is provided with a second gas adjusting ring 35 for enabling the second gas to be supplied uniformly to the gas conduits 5.

  As described above, in the vapor phase growth apparatus 1, the inside of the vapor deposition apparatus 1 is isolated from the atmosphere side, the reaction furnace 14 that maintains an airtight state, the substrate holding member 16 that places the substrate 15 to be processed, and the substrate 15 to be processed are heated. The reaction chamber includes a substrate heater 17 that performs the above operation and a gas supply unit 18 that is provided at a position facing the substrate holding member 16 and has a plurality of gas flow path outlets that supply a plurality of source gases toward the substrate 15 to be processed. 19 is constituted.

  The substrate holding member 16 is provided at one end of the rotation transmission member 20, and the rotation transmission member 20 can be rotated by a rotation mechanism (not shown).

  When forming a thin film on the main surface of the substrate 15 to be processed, a source gas (hereinafter simply referred to as a gas) is introduced from the gas supply unit 18 into the reaction chamber 19. At this time, the processing substrate 15 is heated by the heater 17 through the substrate holding member 16, and a film forming chemical reaction on the processing substrate 15 is promoted, whereby a thin film is formed on the processing substrate 15. The The gas that has passed over the substrate to be processed 15 is discharged from the gas discharge port 21.

  Next, the structure of the gas supply unit 18 will be described more specifically. In FIG. 1, the gas supply unit 18 is sealed so as to maintain an airtight state by a reaction furnace 14 and an O-ring 22a, and the gas supply unit 18 and the reaction furnace 14 are configured to be removable. Yes.

  The gas supply unit 18 is provided with a first gas introduction port 23 and a second gas introduction port 24, and different source gases are supplied to the gas supply unit 18.

  The first gas and the second gas are separated, and a plurality of shower plate-shaped gas flow paths (first gas flow path 4a, second gas flow) for independently discharging each gas into the gas distribution space 9 and the gas distribution space 10. Gas passage 4b), the second gas passage 4b is disposed (concentrically) in each first gas passage 4a, and the first gas passage outlet 25 is connected to the reactor. The second gas flow path outlet 27 formed on the wall surface 26 is configured and arranged on the gas supply source side (that is, the side farther from the substrate 15 to be processed) than the first gas flow path outlet 25. The refrigerant flow path 11 that constitutes the mixing chamber 12 of each first gas and the second gas, and adjusts the temperature of the first gas flow path 4a between the first gas flow path 4a and the reaction furnace wall surface 26 is provided. Composed.

  The upper plate 28 of the first gas flow path and the lower plate 29 of the first gas flow path are formed with a number of through-holes and arranged at a distance A, and the gas conduit 30 serving as the gas flow path 4a. However, it is joined to the through hole by vacuum brazing, electron beam welding, TIG welding, diffusion bonding or the like so as to keep hermeticity. FIG. 3 shows a shape in which both ends of the gas conduit 30 are joined to the upper plate 28 of the first gas flow path and the lower plate 29 of the first gas flow path, respectively, but the present invention is limited to this. Not. The gas conduit 30 may be formed directly on the upper plate 28 or the lower plate 29 by cutting or the like.

  By comprising as mentioned above, the refrigerant | coolant flow path 11 which can adjust the temperature of the gas flow path 4a is formed.

  Furthermore, the flange part of the 1st gas flow path which formed the 1st gas introduction flow path 31 and the refrigerant | coolant flow path 11 in the member comprised by the upper plate 28, the lower plate 29, and the gas conduit 30 of the 1st gas flow path. 32 are joined. Although the flange portion 32 is a separate body here, the flange portion 32 may be formed on either or both of the upper plate 28 and the lower plate 29. As a joining method, any method such as vacuum brazing, electron beam welding, TIG welding, and diffusion joining may be used.

  In addition, a refrigerant adjustment ring 33 is provided in the refrigerant flow path 11 so that the refrigerant can be supplied uniformly. A plurality of holes are formed in the refrigerant adjustment ring 33 so that the refrigerant can be supplied uniformly. The diameter of each hole is appropriately adjusted so that the refrigerant can be supplied uniformly. The shape may be circular, rectangular, or polygonal.

  The member configured as described above is referred to as a shower plate 2.

  The lower plate (base 7) of the second gas flow path is provided with a number of through holes, and the plurality of gas conduits 5 are maintained by vacuum brazing, electron beam welding, TIG welding, diffusion bonding, etc. so as to keep airtightness. It is joined. FIG. 3 shows a shape in which the gas conduit 5 is joined to the second gas flow path lower plate (base 7), but the present invention is not limited to this. The gas conduit 5 may be formed directly on the second gas flow path lower plate (base 7) by cutting or the like.

  The lower plate 29 (base 7) and the upper plate 8 are arranged at a distance B, and are sealed with a fixing screw 39 in an detachable state by an O-ring 22c. By configuring as described above, the gas distribution space 10 is formed. In addition, an adjustment ring 35 is disposed in the gas distribution space 10, and the adjustment ring 35 has a plurality of holes for enabling the second gas to be supplied uniformly. The diameter of each hole is appropriately adjusted so that the second gas can be supplied uniformly. The shape may be circular, rectangular, or polygonal.

  The member configured as described above is called a shower plate 3.

  A shower plate 3 is installed on the shower plate 2 to form a gas distribution space 9 having a distance c. The shower plate 2 and the shower plate 3 are fixed by an O-ring 22c so as to be kept airtight.

  An adjustment ring 36 is disposed in the gas distribution space 9, and the adjustment ring 36 has a plurality of holes for allowing the first gas to be supplied uniformly. The diameter of each hole is appropriately adjusted so that the first gas can be supplied uniformly. The shape may be circular, rectangular, or polygonal.

  The gas flow path outlet 27 of the gas flow path 4b concentrically enclosed in the gas flow path 4a is formed at a distance L from the gas flow path outlet 25. By comprising in this way, the mixing chamber 12 of 1st gas and 2nd gas is formed in the gas flow path 4a.

  By configuring as described above, the mixing property of the reaction gas is improved, the gas concentration distribution on the surface of the substrate to be processed can be made uniform, and the controllability of the surface reaction of the substrate to be processed is improved. While improving a film thickness and a composition ratio, raw material utilization efficiency can be improved.

  In addition, since the coolant channel 11 is configured, it is possible to prevent the addition compound from being generated before reaching the substrate to be processed.

  In the present embodiment, the shower plate 3 is sealed by the O-ring 22b and can be removed, so that the first gas distribution space 9 can be exposed. With the above configuration, maintainability is improved. In particular, even when an additive compound is generated inside the gas shower plate 2 or when foreign substances are mixed in, the cleaning property is dramatically improved and internal contamination is completely removed. it can. According to the structure described in the conventional patent document 3, since it is joined by brazing or the like, it is impossible to completely clean the inside. Since the hole is small (φ0.6 mm), the cleaning liquid cannot flow sufficiently, and stagnation can occur, there is a high possibility that foreign matter will accumulate.

  In the present embodiment, the configuration example in which the shower plate 3 is sealed by the O-ring 22b and is removable is shown, but the present invention is not limited to this. The shower plate 3 may be configured to be removable from the shower plate 2 by other mechanisms.

  As another configuration, the shower plate 3 can be configured to be removable from the shower plate 2 by a “knife edge type metal seal flange” (also referred to as an ICF flange or a conflat flange). Generally, it can be configured to be removable by a vacuum sealable flange type.

  "Knife edge type metal seal flange" was developed by Varian as a flange for ultra-high vacuum and used like a standard flange for ultra-high vacuum. In Japan, the Japan Vacuum Association uses JVIS003 "Vacuum flange shape and dimensions for vacuum equipment" as the name of "Knife-edge type metal seal flange" and the dimensional drawing is described as a reference drawing. On the other hand, the ISO standard is currently being established, and the ISO / CD3669 baked flange is being studied at the draft stage.

  The bakable flange that is going to be standardized by ISO includes other types of seal mechanisms such as knife-edge type, hollow metal “O” ring type, metal “C” ring, etc. We are trying to standardize dimensions.

  The knife-edge type metal seal flange is a joint made of all metal with a pointed edge on the inside and usually sealed by plastic deformation with a copper gasket interposed therebetween. The configuration of such a knife edge type metal seal flange is disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-294146.

  Further, the upper plate 8 of the shower plate 3 is sealed by an O-ring 22c and can be removed, so that the gas distribution space 10 can be exposed. According to the above configuration, since the gas distribution space 10 can be exposed, the maintainability is improved. In particular, when an additive compound is generated in the gas distribution space 10 and the gas flow path 4b, foreign substances are mixed in. Even in such a case, the detergency is greatly improved and internal contamination can be completely removed.

  In the present embodiment, the upper plate 8 of the shower plate 3 is sealed by the O-ring 22c and can be removed. However, the present invention is not limited to this. The upper plate 8 may be configured to be removable from the base 7 by another mechanism. For example, the upper plate 8 can be configured to be removable from the base 7 by the above-described “knife edge type metal seal flange”.

  Moreover, in this Embodiment, although the gas distribution space 9 and 10 showed the structure provided in the upper side of the reaction chamber 19, this invention is not limited to this. Conversely, the apparatus may be configured upside down so that the reaction chamber is on the upper side and the shower is blown up from the gas distribution space side on the lower side. The same applies to other embodiments described later.

  Moreover, in this Embodiment, the front-end | tip of the gas conduit 5 is inserted in the middle of the gas flow path 4a, and the mixing chamber 12 is formed by the inner wall of the gas flow path 4a ahead of the front-end | tip of the gas conduit 5. However, the present invention is not limited to this. The tip of the gas conduit 5 and the wall surface 26 may be configured to be on the same plane, or the tip of the gas conduit 5 may be configured to protrude from the wall surface 26 toward the substrate 15 to be processed. In these cases, the mixing chamber 12 is not formed. The same applies to other embodiments described later.

(Embodiment 2)
FIG. 5 is a cross-sectional view showing the configuration of the vapor phase growth apparatus 1a according to the second embodiment. The same components as those described above are denoted by the same reference numerals. Therefore, detailed description of these components is omitted.

  The difference from the vapor phase growth apparatus 1 of the first embodiment described above is that an elevating mechanism 13 is provided between the shower plate 2 and the shower plate 3. The elevating mechanism 13 is constituted by a bellows. “Bellows” refers to a tube made of metal with pleats to provide stretchability, airtightness, and springiness. In other words, it can be said that the “bellows” is a “expandable tube”.

  The elevating mechanism 13 is formed in the longitudinal direction of the gas conduit 5 in order to adjust the volume of the mixing chamber 12 formed by the tip of the gas conduit 5 and the gas flow path 4a and in which the first gas and the second gas are mixed. It is comprised so that the gas conduit 5 and the gas flow path 4a may be raised-lowered along. Although FIG. 5 shows an example in which the elevating mechanism 13 moves the shower plate 2 and the shower plate 3 relatively up and down along the longitudinal direction of the gas conduit 5, the present invention is not limited to this. The elevating mechanism 13 may be configured to move the gas conduit 5 and the shower plate 3 relatively up and down along the longitudinal direction of the gas conduit 5.

  Thus, the shower plate 2 and the shower plate 3 can be joined via the lifting mechanism 13. According to the above configuration, the position of the shower plate 3 can be changed using the bending of the bellows of the lifting mechanism 13. It is also possible to drive automatically by a drive mechanism (not shown).

  According to the above configuration, the size of the mixing chamber 12 can be changed, the raw material gas mixing property can be improved, and the gas concentration distribution on the surface of the substrate to be processed 15 can be made uniform. The controllability of 15 surface reactions can be improved. That is, the film forming thickness and the composition ratio can be improved, and the raw material utilization efficiency can be improved. In addition, the size of the mixing chamber 12 can be varied during film formation. For this reason, even when growing a plurality of films in which the reaction gas flow rate and the temperature of the substrate 15 to be processed are grown in a single film formation, the optimum size of the mixing chamber 12 can be set for each condition. As a result, an optimal single film can be laminated, and a high-quality multilayer film can be formed.

  Furthermore, by the relative position movement of the gas conduit 5 and the gas flow path 4a, the degree of protrusion of the gas conduit 5 from the gas flow path 4a, the distance from the tip of the gas conduit 5 to the substrate 15 to be processed, the gas flow path 4a Since the distance from the exit can be changed, the film quality and growth rate can be changed.

  By installing a bellows (elevating mechanism 13) by welding or flange connection between the top surface of the shower plate 2 and the bottom surface of the shower plate 3, the gas distribution space 9 is isolated from the outside (atmosphere), and the interior Can be kept airtight, and the height position of the shower plate 3 can be adjusted using the bending of the bellows (elevating mechanism 13). The height position of the shower plate 3 can be driven by various methods such as a ball screw, an air cylinder, and a height adjustment bolt.

(Embodiment 3)
FIG. 6 is an enlarged cross-sectional view illustrating a configuration of a gas supply unit provided in the vapor phase growth apparatus according to the third embodiment. The outer periphery of the gas conduit 5a opposite to the flow path outlet 27a is provided with a male thread. A flange 40 is formed on the side of the flow outlet 27a of the male screw formed in the gas conduit 5a.

  The through hole 41 formed in the lower plate 34 a is subjected to female thread processing corresponding to the male thread of the gas conduit 5 a, and the counterbore hole 42 is formed so as to correspond to the flange 40. Thus, the gas conduit 5a can be fixed to the lower plate 34a by the screw structure. Furthermore, by providing the flange 40, it is possible to accurately define the protruding length D of the gas conduit 5a (without the flange 40, the protruding length D changes according to the tightening condition of the screw. End up). Further, by inserting the flange 40 into the counterbore hole 42 of the lower plate 34a, no extra protrusion is generated in the gas distribution space 9, and the flow in the gas distribution space 9 is not disturbed. Further, since there is a possibility that the first gas and the second gas are diffused and mixed through the screw portion, a graphite sheet can be sandwiched between the screw portion and a sealing structure can be taken. In addition to the graphite sheet, a metal thin film sheet having corrosion resistance against a raw material gas such as a platinum thin film sheet can also be used.

  However, if the height of the flange 40 is a protrusion that does not disturb the flow in the gas distribution space 9, it is not essential to provide the counterbore 42.

  According to the above configuration, the gas conduit 5a is configured to be removable (detachable) from the lower plate 34a, and the size of the mixing chamber 12 can be changed by changing the protruding length D of the gas conduit 5a. Is possible. The position of the gas conduit 5a can be changed also by the method described in the second embodiment. However, since the size of the gas distribution space 9 is variable, depending on the conditions, the reaction gas can be supplied from a uniform shower plate. May not be possible (when the gas distribution space 9 is extremely narrow). In such a case, since the gas conduit 5a can be removed, it is not necessary to remanufacture the main body, and adjustment can be made only by changing the gas conduit 5a. Device.

  Moreover, according to the said structure, the change of the diameter of the 2nd gas flow path exit 27a becomes easy. For example, when the film thickness of the substrate to be processed 15 on the outer peripheral side among the plurality of substrates to be processed 15 installed on the substrate holding member 16 is different from that in the central portion, the temperature on the substrate holding member 16 is usually set. By changing the distribution (increasing or decreasing the temperature of the substrate 15 to be processed arranged on the outer peripheral side) and changing the temperature of the gas phase, a uniform film is formed. However, when the temperature is changed, the film forming composition is also changed. Therefore, it is conceivable to adjust the flow rate of the reaction gas supplied to the substrate 15 to be processed. However, in the case of the shower plate method, changing the flow rate changes the overall flow rate. For each flow rate adjustment, it was necessary to recreate the shower plate with different hole diameters.

  However, the gas flow path 4b having various hole diameters can be easily formed by removing and replacing the gas conduit 5a. In addition, by changing the outer diameter of the gas flow path outlet 27a, that is, the outer diameter of the gas conduit 5a, the cross-sectional area of the gas flow path 4a can be changed, and fine flow rate adjustment can be performed for each area. is there. From the above, it is possible to provide a vapor phase growth apparatus that supports film formation under various conditions.

  In addition, even when an additional compound is generated in a part of the gas flow path 4b, and the additional compound adheres to the wall surface in the gas flow path 4b and the flow path outlet 27a is clogged, the whole is clogged without washing. It is possible to exchange only the gas flow path 4b (gas conduit 5a) at the location. Therefore, the maintenance time of the apparatus can be greatly shortened, and the operating rate of the apparatus can be improved.

In the present embodiment, an example in which a screw is formed on the gas conduit 5a so as to be removable (detachable) from the lower plate 34a has been shown. However, the present invention is not limited to this. The gas conduit 5a may be detachable (detachable) from the lower plate 34a by another mechanism.
As another mechanism, as shown in FIGS. 7 (a) and 7 (b), a flange 40 is provided on the upper part of the gas introduction pipe 5a, and “fitting” such as clearance fit, intermediate fit, tight fit, etc. ] Can be configured to be removable (detachable). However, clearance fit and intermediate fit are preferred because they are easy to remove. The interference fit is preferable in that there is no possibility of unexpected disengagement or displacement due to gas pressure or the like.
Further, assuming that the diameter of the first gas flow path 4a is d1 and the diameter of the flange 40 is d2, the relationship is d1> d2. When d1 <d2, it is impossible to exchange the gas conduit 5a unless the shower plate 2 and the shower plate 3 are separated. However, since d1> d2, the shower plate 2 and the shower plate 3, from the reaction chamber 19 side, the gas conduit 5a can be removed through the first gas flow path outlet 25, removed, and fastened again.
With the above configuration, it is not necessary to remove a vacuum sealing portion such as an O-ring, and the maintainability is improved. Also, if the vacuum seal is removed, there is an increased risk of leakage, and it is necessary to perform a leak check without failing to reduce the operating rate, but there is no need to worry about this.
Further, the outer diameter of the gas conduit 5a may be larger or smaller than the threaded portion, and can be freely set as long as it is equal to or smaller than the diameter d1 of the first gas flow path 4a. The growth conditions such as the above are widened, and the growth conditions with high growth rate and efficiency and high film thickness uniformity are possible.
As shown in FIG. 7 (a), a recess 51 is formed at the distal end (reaction chamber 19 side) of the gas conduit 5a. Further, as shown in FIG. 7B, a convex portion 52 may be formed. In this way, by forming the concave portion 51 and the convex portion 52, a jig can be inserted from the reaction chamber 19 side and the rotation of the gas conduit 5a can be restricted. Therefore, the gas conduit 5a can be easily replaced. It becomes.
FIG. 8B shows an exchange jig 53 for the gas conduit 5a. The exchange jig 53 is provided with a cylindrical jig insertion portion 54 to be inserted into the gas flow path 4b of the gas conduit 5a, and is fitted to the concave portion 51 at the tip (reaction chamber 19 side) of the gas conduit 5a. A jig projection 55 is installed at the base of the jig insertion portion 54. According to the above configuration, when the gas conduit 5a is replaced, there is no possibility that the gas conduit 5a falls due to the jig insertion portion 54 inserted into the gas flow path 4b of the gas conduit 5a. Further, when the concave portion 51 and the jig projection 55 are fitted, rotation restraint can be performed and the screw portion can be rotated. In addition, by setting the outer diameter d3 of the replacement jig 53 to be substantially equal to the diameter of the first gas flow path 4a, it is easy to insert the replacement jig 53 in parallel with the gas conduit 5a. It can be removed without applying force (the gas conduit 5a is so thin that bending may occur. In addition, if stress is applied to the threaded portion, it will cause galling and it will be difficult to remove. The reason for this is that the vacuum parts are the parts where the reaction gas flows, so that oil (grease) cannot be used and is cleaned very cleanly in order to prevent contamination by impurities. ).
Further, the concave-convex relationship between the concave portion 51 and the jig convex portion 55 may be reversed, and may be one, two, or more as long as rotation restraint can be achieved.

  If the gas conduit 5a is to be attached / detached from the gas distribution space 10, the maintenance becomes difficult. Although the reaction chamber 19 may be opened by normal maintenance, the gas distribution space 10 basically has no opportunity to be opened. Therefore, when the gas conduit 5a is to be attached or detached from the gas distribution space 10 side, it is purposely opened. It is necessary and the utilization rate decreases.

  If the gas conduit 5a is to be attached / detached from the gas distribution space 10 side, the nozzle diameter of the gas conduit 5a is also limited to the screw diameter of the gas conduit 5a, so that the growth conditions such as the flow rate and flow rate are limited, and the growth rate and efficiency This makes it difficult to optimize growth conditions with high film thickness uniformity. Further, when the gas conduit 5a is to be attached / detached from the gas distribution space 10 side, a problem arises in that turbulence is generated because the nozzle protrudes into the gas supply chamber.

  When the gas conduit 5a can be detached from the reaction chamber side, it is not necessary to remove the O-ring or other vacuum sealing part, and the maintainability is improved. (When the vacuum sealing part is removed, a leak check must be performed. (This causes a reduction in operating rate and increases the risk of leakage.)

  When the outer diameter of the gas conduit 5a is limited to a screw diameter or less, the gas flow path 4a can be limited. Therefore, growth conditions such as flow rate and flow rate are limited, and it becomes difficult to optimize growth conditions with high growth rate, efficiency, and film thickness uniformity.

  If the gas conduit 5a can be replaced and changed, it is possible to adjust the state of the gas reaching the substrate 15 by simply replacing the gas conduit 5a regardless of whether or not the mixing chamber 12 is formed. become. The state of the gas that can be adjusted includes the gas mixing ratio, the degree of gas mixing, the degree of gas reaction, the gas reaction rate, the gas amount, the main gas flow direction, and the presence / absence of turbulent flow in the vicinity of the substrate 15 to be processed.

Further, when the mixing chamber 12 is formed, not only the size of the mixing chamber 12 can be adjusted, but also the following adjustment is possible. For example, if the gas conduit 5a has the same length, the size of the space (mixing chamber 12) in front of the tip is the same, but a gas cylinder type gas conduit (gas conduit 5a) having an open front end as shown in FIG. Even so, according to the difference in the inner diameter, the state in which the gas is mixed (the degree of mixing, the speed of flowing out from the outlet, the outflow direction, etc.) can be variously adjusted. Further, in the type having an opening in the closed surface of the tip as shown in FIG. 9A, the gas is mixed (the degree of mixing, the speed at which the gas flows out from the outlet) according to the arrangement, size and number of the openings. , Outflow direction, etc.) can be adjusted in various ways. Also, depending on whether the direction of gas pipe ejection is from the end face as shown in FIG. 9 (a) or from the side face as shown in FIG. 9 (b), The state in which the gas is mixed (the degree of mixing, the speed at which the gas flows out from the outlet, the outflow direction, etc.) can be variously adjusted. Furthermore, the gas conduit of the type shown in FIG. 9 (a) in which an opening is formed on the closed surface of the distal end depends on whether it opens perpendicularly or obliquely with respect to the closed surface of the distal end. The state in which the gas is mixed (the degree of mixing, the speed at which the gas flows out from the outlet, the flow direction, etc.) can be variously adjusted.
FIG. 9A is a perspective view showing the configuration of the gas conduit 5a provided in the gas supply section of the vapor phase growth apparatus, and FIG. 9B is a perspective view showing the configuration of another gas conduit 5b. According to the configuration shown in FIG. 9A, it is possible to further widen the ejection of the second gas by forming a plurality of holes 6 at the outlet of the gas conduit 5a (in the case of a pipe shape, a straight line). The second gas outflow velocity from each hole 6 is increased as compared with the conventional case, and fine injection with a narrow pitch can be realized. For this reason, the turbulence of the second gas that flows out increases, and the miscibility with the first gas is further improved. Further, the gas concentration distribution on the surface of the substrate to be processed can be made uniform, and the controllability of the surface reaction of the substrate to be processed can be improved. be able to.

  According to the configuration of FIG. 9B, a plurality of holes 6 are formed in the side surface of the gas conduit 5b, thereby ejecting the second gas into the first gas flow path in the side surface direction. Since the second gas outflow rate from each hole 6 is increased as compared with the prior art and is ejected to the first gas flow path, the mixing property of the outflowed second gas and the first gas is further improved.

(Embodiment 4)
FIG. 10 is a cross-sectional view showing the configuration of the vapor phase growth apparatus 1b according to the fourth embodiment. The vapor phase growth apparatus 1b is a vertical showerhead type MOCVD apparatus which is a fourth embodiment of the MOCVD apparatus.

  A large number of through holes are formed in the intermediate plate 43 and the lower plate 34 of the shower plate 3. The intermediate plate 43 and the lower plate 34 are disposed at a distance E, and the gas conduit 5 serving as the gas flow path 4b is placed in each through-hole so as to maintain airtightness, such as vacuum brazing or electron beam. Joined by welding, TIG welding, diffusion bonding, or the like. Further, the gas conduit 5 may be formed directly on the intermediate plate 43 or the lower plate 34 by cutting or the like.

  By comprising as mentioned above, the refrigerant | coolant flow path 44 which can adjust the temperature of the gas flow path 4b is formed.

  With the above configuration, the temperature can be adjusted to a desired temperature regardless of the temperature rise of the gas flow path outlet 27 due to heating from the heater 17 (FIG. 1).

  Further, in the case of the above configuration, since the gas flow path outlet 27 and the refrigerant flow path 44 are separated from each other, in order to improve the temperature controllability of the gas flow path 4b, a gas conduit with a high thermal conductivity is used. 5 is desirable.

  For example, SUS304 (thermal conductivity 16 W / (m · K)), SUS316L, or the like is usually used, but molybdenum (thermal conductivity 138 W / (m · K)), tungsten (thermal conductivity 178 W / (m · K)). K)), platinum (thermal conductivity 71.4 W / (m · K)), nickel (thermal conductivity 90.5 W / (m · K)), and the like can be used.

  In the present invention, it is needless to say that the shapes of the reaction furnace, shower plate and other members constituting the MOCVD apparatus are not limited to the shapes shown in FIG.

  In the above-described first to fourth embodiments, the first gas may be a group III gas, and the second gas may be a group V gas.

  In the present invention, examples of the group III element include Ga (gallium), Al (aluminum), and In (indium). Examples of the group III gas containing the group III element include trimethylgallium (TMG). ) Or one or more organic metal gases such as trimethylaluminum (TMA) can be used.

Examples of the group V element include N (nitrogen), P (phosphorus), and As (arsenic). Examples of the group V gas containing the group V element include ammonia (NH ₃ ), phosphine (PH ₃ ). ) Or one or more hydrogen compound gases such as arsine (AsH ₃ ) can be used.

  According to the above configuration, the second gas flow path outlet 27 directly receives heat from the heater, and has a structure in which the temperature rises more easily than the first gas flow path 4 a whose temperature is adjusted by the refrigerant flow path 11. An organic gas is used as the group V gas. Unless the temperature is increased, molecules are decomposed and are not doped into the growth film, or are doped as molecules to form holes, leading to deterioration in film quality and growth rate. Therefore, by setting the second gas flow path 4b to be a group V gas, the temperature of the substrate to be processed 15 is increased by supplying the activated gas to the reaction furnace 14 in advance by heating it outside the reaction furnace 14. It is possible to proceed the gas phase reaction while maintaining a temperature at which the Group III gas is not thermally decomposed.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  The present invention relates to a vapor phase growth comprising a shower plate disposed to face a substrate holding member for placing a substrate to be processed in a reaction furnace and provided to supply gas toward the substrate to be processed. The present invention can be applied to an apparatus and a vapor deposition method.

1 is a cross-sectional view showing a configuration of a vapor phase growth apparatus according to a first embodiment. It is sectional drawing which shows the detailed structure of the said gas supply part. It is an expanded sectional view of the A section shown in FIG. It is the top view which looked at the gas supply part provided in the said vapor phase growth apparatus from the to-be-processed substrate side. FIG. 3 is a cross-sectional view showing a configuration of a vapor phase growth apparatus according to a second embodiment. FIG. 6 is an enlarged cross-sectional view illustrating a configuration of a gas supply unit of a vapor phase growth apparatus according to a third embodiment. (A) is a perspective view which shows the structure of the other gas conduit provided in the gas supply part of the said vapor phase growth apparatus, (b) is a perspective view which shows the structure of another gas conduit. (A) And (b) is a perspective view for demonstrating the structure of the exchange jig of the said gas conduit | pipe. (A) is a perspective view which shows the structure of the gas conduit | pipe provided in the gas supply part of the said vapor phase growth apparatus, (b) is a perspective view which shows the structure of another gas conduit | pipe. FIG. 6 is a cross-sectional view showing a configuration of a vapor phase growth apparatus according to a fourth embodiment. It is sectional drawing which shows the structure of the conventional vapor phase growth apparatus typically.

Explanation of symbols

1 Vapor growth equipment 2 Shower plate (first shower plate)
3 Shower plate (second shower plate)
4a, 4b Gas flow path 5 Gas conduit 6 Hole 7 Base 8 Upper plate (cover plate)
9 Gas distribution space (first gas distribution space)
10 Gas distribution space (second gas distribution space)
DESCRIPTION OF SYMBOLS 11 Refrigerant flow path 12 Mixing chamber 13 Elevating mechanism 14 Reaction furnace 15 Substrate 16 Substrate holding member 51 Concave part 52 Convex part 53 Replacement jig 54 Jig insertion part 55 Jig protrusion part

Claims (12)

A first shower plate that is disposed to face a substrate holding member on which a substrate to be processed in the reaction furnace is placed and supplies a first gas toward the substrate to be processed;
A vapor phase growth apparatus comprising: a second shower plate disposed on an opposite side of the substrate holding member to the first shower plate and supplying a second gas toward the substrate to be processed;
The first shower plate has a gas flow path through which the first gas flows toward the substrate to be processed.
The second shower plate has a gas conduit that protrudes from the second shower plate and is inserted into the gas flow path to flow the second gas toward the substrate to be processed.
The gas conduit is detachably attached to the second shower plate ,
A vapor phase growth apparatus characterized in that a plurality of holes are formed at the outlet of the gas conduit . A first gas distribution space for supplying the first gas to the gas flow path is formed between the first shower plate and the second shower plate;
2. The vapor phase growth apparatus according to claim 1, wherein the second shower plate is detachably provided from the first shower plate so that the first gas distribution space is exposed. The second shower plate has a base and a cover plate,
A second gas distribution space is formed between the base and the cover plate;
The vapor phase growth apparatus according to claim 1, wherein the cover plate is detachably provided from the base so that the second gas distribution space is exposed. The vapor phase growth apparatus according to claim 1, wherein a refrigerant flow path for flowing a refrigerant for adjusting the temperature of the gas conduit is formed in the second shower plate. The first gas includes a group III gas,
The vapor phase growth apparatus according to claim 1, wherein the second gas includes a group V gas. The vapor phase growth apparatus according to claim 1, further comprising an elevating mechanism for moving the gas conduit and the gas flow path relatively up and down along a longitudinal direction of the gas conduit. The vapor deposition apparatus according to claim 6, wherein the lifting mechanism relatively lifts and lowers the first shower plate and the second shower plate along a longitudinal direction of the gas conduit. The vapor phase growth apparatus according to claim 6, wherein the elevating mechanism moves the gas conduit and the second shower plate relatively up and down along the longitudinal direction of the gas conduit. The gas conduit has a flange mating with the second shower plate;
The vapor phase growth apparatus according to claim 1, wherein an outer diameter of the flange of the gas conduit is smaller than an inner diameter of the gas flow path. The vapor phase growth apparatus according to claim 1, wherein a groove or a protrusion that fits with an exchange jig of the gas conduit is formed at a tip of the gas conduit. The said 1st shower plate has the mixing chamber which is formed by the inner wall of the said gas flow path ahead of the front-end | tip of the said gas conduit, and mixes the said 1st gas and the said 2nd gas. Vapor growth equipment. A first shower plate disposed opposite to a substrate holding member on which a substrate to be processed in a reaction furnace is placed, wherein a gas flow path through which a first gas flows toward the substrate to be processed is formed. The first gas is supplied toward the substrate by the shower plate,
A second shower plate disposed on the opposite side of the substrate holding member with respect to the first shower plate, protruding from the second shower plate and inserted into the gas flow path toward the substrate to be processed. A vapor phase growth method for supplying the second gas toward the substrate to be processed by a second shower plate having a gas conduit for flowing a second gas.
The gas conduit is detachably attached to the second shower plate,
A gas phase growth method, wherein a plurality of holes are formed at an outlet of the gas conduit.

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