Vertical MOCVD (Metal Organic Chemical Vapor Deposition) gas homogenizing device

Abstract

The invention discloses a vertical MOCVD (Metal Organic Chemical Vapor Deposition) gas uniformizing device, which comprises a sealing cover flange, a gas uniformizing device and a gas uniformizing device, an overflowing gap is formed between the inner pipe and the hole wall of the center hole, and the inner pipe correspondingly provides an inner flow channel; the inner pipe is sleeved with the sleeve, and an outer flow channel communicated with the overflowing gap is formed between the sleeve and the inner pipe; an MO source pipe joint connected to the inner pipe; the first process gas pipe joint is connected to the central hole; the middle disc is connected to the lower side of the upper disc, an upper air uniformizing cavity is formed between the middle disc and the upper disc, and seat holes are distributed in the middle disc; the air distribution pipe is mounted in the seat hole; a lower air uniformizing cavity communicated with the inner flow channel is formed between the lower disc and the middle disc; the lower disc is a porous disc, and part of holes in the lower disc serve as via holes for air distribution pipes to penetrate through. According to the gas uniformizing device disclosed by the invention, the pre-reaction of the MO source and the process gas can be effectively reduced under the condition that the gas uniformizing effect is relatively good.

Description

Technical Field

[0001] The present invention relates to a vertical MOCVD gas homogenizing device, wherein MOCVD is the abbreviation of Metal-organic Chemical Vapor Deposition, i.e. metal organic compound chemical vapor deposition. The vertical type is also called vertical type. Background Art

[0002] The MOCVD process is used to grow compound semiconductor materials such as III-V gallium nitride and gallium arsenide, and is currently widely used in optoelectronic product industries such as LEDs. Currently, the MOCVD equipment widely used by production companies is the products of two brands, AXITRON of Germany and VEECO of the United States. The MOCVD equipment produced by the above two companies is a way to separate the two types of process gases into the reaction chamber to ensure the normal gas transmission process.

[0003] The vertical MOCVD equipment includes a vertically arranged reaction chamber, and the reaction chamber, for example, has an air inlet on the upper cover plate for the entry of process sources and process gases. The reaction chamber, for example, has a central hole on the lower cover plate, and an axis inserted into the reaction chamber is provided through the central hole. The upper end of the axis is equipped with, for example, a graphite carrier or a quartz carrier, etc., on which a substrate is carried, and the carrier is generally aligned with the center of the air inlet. The air inlet is generally equipped with a central sleeve structure, that is, a nested pipeline is generally used for gas delivery, wherein the central tube generally passes through the process source, and the sub-outer channel generally passes through a process gas, and finally a nozzle is arranged at the end of the sleeve structure for uniform gas. A guide cone is provided in the nozzle nozzle corresponding to the central tube to disperse the process source outward. Similarly, the pipeline nested outside has an outward-floating cone at the lower end to disperse the corresponding gas outward.

[0004] Since the cross-sectional area of ​​the nozzle itself is relatively small, and the table area of ​​the wafer stage used for wafer loading is relatively large, the ejected gas needs to have a certain degree of dispersion before reaching the substrate to cover the substrate on the wafer stage. In this process, when a III-V group nitride semiconductor material with a high aluminum component such as a UV component is grown, the Al source (such as trimethylaluminum, such a source is called MO source in the art, i.e. Metal Organic Source) and NH3 have contacted before reaching the reaction area, and thus a strong pre-reaction will occur, which makes it difficult for Al atoms and N atoms to migrate in the epitaxial layer above the substrate.

[0005] In view of this, in some implementations, the stage is rotated and the nozzles are arrayed to achieve gas uniformity, but the distance between the nozzles and the stage is still relatively far, and it is still unable to overcome the problem of strong pre-reaction between the Al source and NH3 before reaching the reaction area.

[0006] It should also be noted that the reaction chamber needs to maintain a predetermined process temperature, and the temperature of the gas introduced into the reaction chamber from the top is usually much lower than the process temperature. Based on thermal convection, it can be seen that the descending gas will be supported by the hot gas below, that is, the so-called thermal buoyancy phenomenon will be generated. In view of this, there is currently a way to push the wafer stage upward to the vicinity of the upper cover plate, and reduce the axial size of the reaction chamber to overcome the thermal buoyancy phenomenon. It should be known that for cover plates such as upper cover plates, it is necessary to avoid excessively high temperatures on the outer surface. The upper cover plate is generally configured as a water-cooled flange, that is, the upper cover plate is often relatively low in temperature. If the upper cover plate is too close to the wafer stage, it will inevitably increase energy consumption, and because the cooling flange is too close to the wafer stage, it may cause the temperature field in the reaction zone to be unstable. Summary of the invention

[0007] The object of the present invention is to provide a vertical MOCVD gas homogenizing device which can effectively reduce the pre-reaction between the MO source and the process gas while ensuring a relatively good gas homogenizing effect.

[0008] According to an embodiment of the present invention, a vertical MOCVD gas homogenizing device is provided, comprising: A cover flange is provided with a central hole and has an inner cover surface and an outer cover surface based on the cover; An inner tube passes through the central hole, wherein at least the outer diameter of the inner tube that matches the central hole is smaller than the diameter of the central hole, so as to form a flow gap between the inner tube and the wall of the central hole, and the inner tube provides an inner flow channel accordingly; A sleeve is sealed and connected to the inner cover surface of the sealing flange and sleeved outside the inner tube to form an outer flow channel communicating with the flow gap between the sleeve and the inner tube, and the overhanging end of the sleeve has an upper plate; An MO source pipe joint connected to the inner pipe to provide an MO source to the inner flow channel; a first process gas pipe joint connected to the central hole to provide a first process gas to the outer flow channel; The middle plate is connected to the lower side of the upper plate, and an upper uniform air cavity communicating with the outer flow channel is formed between the middle plate and the upper plate, and seat holes are distributed on the middle plate; Air distribution pipes are installed in the seat holes in a one-to-one correspondence and extend downward; and The lower plate is connected to the lower side of the middle plate, and a lower air-distributing cavity connected to the inner flow channel is formed between the lower plate and the middle plate; the lower plate is a porous plate, and some holes on the lower plate are used as through holes for the air distribution pipe to pass through.

[0009] Optionally, the length of the sleeve extending downward from the sealing flange is 0.72 to 0.80 times the diameter of the reaction chamber.

[0010] Optionally, the upper plate, the lower plate and the middle plate are connected by flanges; Correspondingly, the upper plate has an upper flange extending downward to form an upper air-distributing cavity side wall, and the lower plate has a lower flange extending upward to form a lower air-distributing cavity side wall.

[0011] Optionally, the air distribution duct head passes downward from the lower plate to expose the air distribution head, and the length of the air distribution head is 4 to 6 times the inner diameter of the air distribution duct.

[0012] Optionally, the diameter of the air-distributing holes on the lower plate for air distribution is 0.5 to 0.7 times the diameter of the inner hole of the air distribution pipe; The air holes are arranged around the air distribution duct.

[0013] Optionally, the upper end of the sleeve has a connecting flange to be connected to the inner cover surface of the cover flange through the flange connection; The axis of the connecting flange is collinear with the axis of the central hole; An outer barrel sleeved on the inner tube is connected to the outer end of the central hole, a gas supply cavity is formed between the outer barrel and the inner tube, and one side of the outer barrel is connected to the first process gas pipe joint; The bottom of the outer barrel is correspondingly used for sealing the upper end of the outer barrel body.

[0014] Optionally, the inner tube comprises a first inner tube section and a second inner tube section connected to each other, wherein the first inner tube section is used to access the reaction chamber from the outside and is partially located in the sleeve; Most of the second inner tube section is located in the sleeve, and the end exposed downward relative to the sleeve is used for connecting the inner flow channel with the lower uniform air cavity.

[0015] Optionally, the second inner pipe section is connected to the sleeve by a plurality of radial connecting plates for heat exchange; Correspondingly, the outer surface of the sleeve section that is used to cooperate with the second inner pipe section is provided with heat exchange fins.

[0016] Optionally, the sealing flange is further connected to a second process gas pipe joint to introduce a second process gas; Correspondingly, an air outlet is provided on the inner cover surface of the sealing flange.

[0017] Optionally, a sealing gas homogenizing cavity is formed in the sealing flange for homogenizing the second process gas; Correspondingly, the air outlets are distributed on the inner cover surface corresponding to the sealing air uniforming cavity; The second process gas pipe joint is connected to the sealing gas uniforming cavity.

[0018] In an embodiment of the present invention, the vertical MOCVD gas homogenizing device provided includes a sealing flange for installing the vertical MOCVD gas homogenizing device at the upper opening of the reaction chamber and for sealing the upper opening of the reaction chamber. Then, a nested inner tube and a sleeve (hereinafter referred to as a nested tube) are used to overhang the gas homogenizing portion used for gas homogenization into the reaction chamber, and a gas homogenizing portion is constructed at the lower end of the nested tube. Since the MO source is isolated from the first process gas before it reaches the gas homogenizing portion, no pre-reaction will occur regardless of whether the temperature of the nested tube has reached the reaction temperature between the MO source and the first process gas. At the same time, since the gas homogenizing portion is far away from the sealing flange, it is less affected by the cooling of the sealing flange. Similarly, the reaction zone in the reaction chamber is relatively far away from the sealing flange based on the overhang of the nested tube, and is also less affected by the cooling of the water-cooled flange. In addition, since the MO source and the first process gas are transported through the nested tube, the gas transport is relatively less affected by thermal buoyancy. It can be seen that the vertical MOCVD provided in the embodiment of the present invention can effectively reduce the pre-reaction of the MO source and the process gas under the condition of ensuring a relatively good gas homogenizing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the main cross-sectional structure of a vertical MOCVD gas homogenizing device in one embodiment.

[0020] Figure 2 for Figure 1 Enlarged view of part I.

[0021] Figure 3 It is a schematic diagram of the structure of the nested tube part with heat exchange function in one embodiment.

[0022] In the figure: 1. gas uniformity part, 2. casing, 3. outer flow channel, 4. inner tube, 5. gas outlet, 6. water cooling flange, 7. first process gas pipe joint, 8. MO source pipe joint, 9. second process gas pipe joint.

[0023] 11. Screws, 12. Upper air-distributing cavity, 13. Middle flange, 14. Screws, 15. Lower flange, 16. Wind shield, 17. Inner pipe head, 18. Lower air-distributing cavity, 19. Air distribution duct.

[0024] 21. Upper flange, 22. Heat exchange fins, 23. Connecting plate.

[0025] 41. Internal flow channel. DETAILED DESCRIPTION

[0026] It should be known that for the vertical MOCVD gas homogenizing device, it is applied to the vertical MOCVD equipment and is installed on the upper part of the vertical MOCVD equipment, and is generally directly used for sealing the upper end of the reaction chamber of the vertical MOCVD equipment. Figure 1The water-cooling flange 6 shown in the figure has a certain inner flange surface and an outer flange surface. Since it is used for sealing the upper end of the reaction chamber, it can be called a sealing flange.

[0027] exist Figure 1 In the illustrated structure, the sealing flange adopts a water-cooled flange 6 as shown in the figure, mainly because the process temperature in the reaction chamber is generally high, and the existence of the water-cooled flange 6 is mainly used to avoid the occurrence of injuries such as scalding.

[0028] In addition, in some embodiments, the inner surface of the water-cooling flange 6 may be provided with, for example, a heat-insulating layer to reduce heat loss in the reaction chamber.

[0029] It should be known that the MO source is a metal organic compound diluted in a carrier gas. Nitrogen or hydrogen is generally used as a carrier gas in the MOCVD process. In other words, the MO source is to deliver MO into the reaction chamber in a gas transport manner. This is common knowledge in the art and will not be elaborated here.

[0030] In an embodiment of the present invention, a nested tube consisting of a sleeve 2 and an inner tube 4 is mainly used to position the gas homogenizing section 1 deeper into the reaction chamber, so that a graphite carrier for carrying a substrate, for example, is relatively close to the gas homogenizing section 1. Specifically, the gas homogenizing section 1 is placed in the reaction zone, which can avoid a pre-reaction between the MO source and, for example, the first process gas outside the reaction zone while ensuring better gas homogenizing capability.

[0031] More specifically, the gas homogenizing section 1 is located at the upper part of the reaction zone, so that a certain gas homogenizing distance is left between the gas homogenizing section 1 and the wafer stage, thereby ensuring a relatively good gas homogenizing effect.

[0032] exist Figure 1 In the structure of the illustrated vertical MOCVD gas homogenizing device, the water-cooling flange 6 used as a sealing flange has a central hole to introduce the reaction gas into the reaction chamber from the outside.

[0033] Obviously, based on Figure 1 The structure and properties of the vertical MOCVD device are shown in the example. The upper surface of the water-cooling flange 6 is its outer surface, and the lower surface is its inner surface. In order to distinguish them, the outer surface of the water-cooling flange 6 is called the outer cover surface, and the inner surface is called the inner cover surface.

[0034] The center hole is mainly used as a via for the insertion of related pipelines. Figure 1 In the illustrated structure, the pipeline part used to construct the outer flow channel 3 is split, that is, the sleeve 2 in the figure is split. For the convenience of description, the two split parts of the sleeve 2 are distinguished as an upper sleeve and a lower sleeve in terms of positional relationship.

[0035] Among them, the upper sleeve is a barrel-type structure, which is fixed to the outer end of the center hole by welding, for example, and the lower sleeve is a pipe body with upper and lower flanges, and is fixed to the inner cover surface of the water-cooling flange 6 through the upper flange by flange connection.

[0036] And it is obvious that the inner hole diameter of the lower casing is greater than or equal to the center hole diameter, and the inner hole of the lower casing and the center hole should maintain relatively good coaxiality. Ideally, the axis of the lower casing is collinear with the axis of the center hole.

[0037] The inner tube 4 passes through the central hole, and the axis of the inner tube 4 and the axis of the central hole are collinear under ideal conditions and maintain relatively good coaxiality as much as possible.

[0038] At the same time, the outer diameter of the inner tube 4 is smaller than the diameter of the center hole. Under this condition, a flow gap will be left between the inner tube 4 and the wall of the center hole. Based on the matching form of the aforementioned sleeve 2, the flow gap constitutes a part of the outer flow channel 3.

[0039] Furthermore, the lumen of the inner tube 4 forms an inner flow channel 41, and the inner flow channel 41 is used for flowing the MO source, and the outer flow channel 3 is used for flowing the first process gas.

[0040] As an external structure of the nested tube, a sealing connection is adopted between the sleeve 2 and the wall of the central hole or the corresponding part defining the central hole, such as the water cooling flange 6.

[0041] Since the sealing connection is a static connection, the corresponding sealing form is a static seal, and the expected sealing is easy to achieve.

[0042] In particular, as described above, the sleeve 2 is a component, the upper sleeve can be welded to the upper end of the center hole, and the sealing requirement between the lower sleeve and the water-cooling flange 6 is relatively low, and can be directly connected by flange connection without the need for additional sealing members. However, in a preferred embodiment, a sealing ring, such as a rubber O-ring, can be provided between the upper flange of the sleeve 2 and the inner cover surface of the water-cooling flange 6.

[0043] exist Figure 1 In the illustrated structure, the outer end of the center hole has a countersink, and the center hole can also be a threaded hole, and is threadedly connected to the upper sleeve. If the countersink is used, the upper sleeve and the countersink can be connected by welding.

[0044] As mentioned above, the sleeve 2 has an upper flange and a lower flange, wherein in order to describe the overall Figure 1 In the gas-distributing part 1 shown in FIG, the lower flange of the casing 2 is called the upper plate. Figure 2 In the illustrated structure, the upper plate constitutes a flange and is referred to as an upper flange plate 21 .

[0045] Obviously, for example, the upper flange 21 must be the main mounting base for the other components of the gas homogenizing section 1. Figure 2 In the middle, the middle flange 13 constituting the middle plate is connected to the lower side of the upper flange 21 , and an upper uniform air cavity 12 communicating with the outer flow channel 3 is formed between the middle flange 13 and the upper flange 21 .

[0046] Obviously, the upper air-uniform cavity 12 is isolated from the inner tube 4 at least in the middle and upper part of the air-uniform portion 1. Therefore, the inner tube 4 extends further downward relative to the sleeve 2 and passes through the upper air-uniform cavity 12 to isolate the upper air-uniform cavity 12 from the inner tube 4 in the middle and upper part of the air-uniform portion 1.

[0047] The upper uniform air cavity 12 is uniformly aired downwardly Figure 2 In order to achieve uniform air flow in the upper air cavity 12, seat holes are distributed on the middle flange 13 for installing the air distribution pipe 19 shown in the figure.

[0048] Furthermore, the air distribution duct 19 corresponding to the seat hole one by one is installed on the seat hole and extends downward. Obviously, the downward extension length should be sufficient to expose or flush the lower end of the air distribution duct 19 from the lower surface of the lower flange 15 shown in the figure to avoid being blocked by the lower flange 15.

[0049] exist Figure 2 In the embodiment, the seat hole has a countersunk hole, and the air distribution pipe 19 has, for example, a cylindrical pipe head, which is accommodated in the countersunk hole to form positioning and limiting.

[0050] The lower flange 15 used as the lower plate is connected to the lower side of the middle flange 13, and a lower air-distributing cavity 18 communicating with the inner flow channel 41 is formed between the lower flange 15 and the middle flange 13. The lower flange 15 is a porous plate, and some of the holes distributed on the lower flange 15 are used as through holes for the air distribution pipe 19 to pass through, and some of the holes constitute air-distributing holes for the lower air-distributing cavity 18 to distribute air downward.

[0051] In this way, the air distribution pipe 19 is used for the uniformity of the first process gas, and the uniformity hole is used for the uniformity of the MO source. The uniformity portion is obviously located at the end of the nested tube, that is, the lower end, which is necessarily far away from the water-cooled flange 6, so that it is less affected by the cooling of the water-cooled flange 6.

[0052] In addition, the nested tubes will be gradually heated during the gas delivery process, which is beneficial for the process gas to reach the reaction zone before reaching the reaction zone. The temperature step required by the reaction zone is reduced, which is beneficial for the rapid reaction. In addition, the process gas in the delivery pipeline is less affected by thermal buoyancy, so that the reaction gas can be more smoothly delivered to the reaction zone, rather than being accumulated at the top of the reaction chamber under the influence of thermal buoyancy, thereby providing a variety of raw material gas utilization rates including MO source.

[0053] The outer flow channel 3 is then matched with a first process gas pipe joint 7. Since the flow gap between the center hole and the inner tube 4 constitutes a part of the outer flow channel 3, the first process gas pipe joint 7 can be directly matched with the center hole. In some other embodiments, the first process gas pipe joint 7 is connected to the upper casing.

[0054] The first process gas pipe joint 7 is used to provide the first process gas to the outer flow channel 3. It should be known that various process gases are generally supplied by gas cylinders in the art. This is common knowledge in the art and will not be elaborated here.

[0055] Correspondingly, the portion of the inner tube 4 where the sealing flange is exposed is provided with a pipe joint connected to the MO source system pipeline, namely the MO source pipe joint 8 shown in the figure.

[0056] The aforementioned technical effect of the nested tubes cantilevering deep into the reaction chamber is reflected in, for example, the effect of the cooling of the cooling flange 6 on the temperature field of the reaction zone. The depth of the nested tube cantilevering should not be too large, otherwise the reaction chamber will be correspondingly enlarged to meet the requirements of the nested tube cantilevering.

[0057] Furthermore, the length of the sleeve 2 in the reaction chamber determines the insertion depth of the gas uniforming portion 1. Therefore, the insertion depth of the gas uniforming portion 1 is determined by the length of the sleeve 2 in the reaction chamber, that is, the length of the lower sleeve. Specifically, the length of the lower sleeve is the length extending downward from the sealing flange. The length is positively correlated with the diameter of the reaction chamber and is expressed as 0.72 to 0.80 times the diameter of the reaction chamber, preferably 0.758 times. Under the condition that the reaction chamber is relatively compact, the influence of the cooling flange 6 on the reaction zone can be effectively reduced.

[0058] Based on the above description, it can be known that the upper plate, the lower plate and the middle plate are connected by flanges, and the corresponding structures are as follows: Figure 2 The upper flange 21, the middle flange 13 and the lower flange 15 shown in the figure have relatively low requirements for sealing between the upper uniform air cavity 12 and the lower uniform air cavity 18, and can purely rely on the surface matching to achieve mechanical contact sealing, which is suitable for the sealing requirements under relatively high process temperatures.

[0059] Correspondingly, the upper plate has an upper flange extending downward to form an upper air-distributing cavity side wall, and the lower plate has a lower flange extending upward to form a lower air-distributing cavity side wall.

[0060] In addition, based on the flange connection, Figure 2 In the illustrated structure, the flange connection uses screws 11 and screws 14 shown in the figure as fasteners, which are convenient for disassembly and assembly as needed.

[0061] As mentioned above, the outer flow channel 3 is used to connect the first process gas, and the inner flow channel 41 is used to introduce the MO source. Regarding the gas homogenization, the two adopt slightly different gas homogenization methods, or they can adopt the same gas homogenization method. Figure 2 In the illustrated structure, the pipe head of the air distribution pipe 19 passes downward from the lower plate to expose the air distribution head, and the length of the air distribution head is 4 to 6 times the inner diameter of the air distribution pipe. Under this condition, the first process gas is mixed with the MO source in a roughly surrounded form.

[0062] Furthermore, the diameter of the gas-uniform holes on the lower plate for uniform gas is 0.5 to 0.7 times the diameter of the inner hole of the air distribution pipe; and the gas-uniform holes are arranged around the air distribution pipe, which is conducive to relatively sufficient mixing of the MO source and the first process gas.

[0063] Regarding the sleeve 2, the portion located outside the reaction chamber is the upper sleeve mentioned above. Figure 1 The illustrated structure is a barrel-type structure, that is, a cylinder with one end sealed with a barrel bottom.

[0064] The bottom of the barrel is provided with a through hole for airtight connection with the inner tube 4, and the through hole and the inner tube 4 may be welded or threaded. The threaded connection may be sealed using, for example, a sealant.

[0065] After the upper sleeve is sleeved on the inner tube 4, an air supply cavity is defined between the upper sleeve, the inner tube 4 and the outer cover surface of the water-cooling flange 6. Figure 1 As shown, the first process gas pipe connection 7 is connected to the gas supply chamber from one side.

[0066] from Figure 1 As can be seen, the inner tube 4 also has two tube sections, and has a first inner tube section and a second inner tube section connected to each other by a tube connection, wherein the first inner tube section is used to connect to the reaction chamber from the outside, has a relatively small tube diameter, and Figure 1 As can be seen in the figure, the first inner pipe section is partially located in the casing 2, specifically in the lower casing 2.

[0067] Most of the second inner pipe section is located in the sleeve 2 , and the end exposed downward relative to the lower end of the sleeve 2 is used for connecting the inner flow channel with the lower uniform air chamber 18 .

[0068] The above structure, on the one hand, slows down the flow rate of the MO source gas flow by changing the diameter of the first inner tube section and the second inner tube section, forming primary homogenization, which is beneficial to overall homogenization. On the other hand, the two-stage structure is conducive to configuring different tube sections according to different needs.

[0069] Furthermore, in some embodiments, Figure 3 As shown, the second inner pipe section is connected to the sleeve through four radially arranged connecting plates 23 for heat exchange.

[0070] Furthermore, correspondingly, the outer surface of the casing section of the casing 2 that cooperates with the second inner pipe section is provided with heat exchange fins 22, so that the process gas is gradually heated during its downward flow, so that the expected process temperature of the reaction zone can be reached in a relatively short time during gas homogenization.

[0071] contrast Figure 1 The tube section of the sleeve 2 having the heat exchange fins 22 is mainly located below the connection between the first inner tube section and the second inner tube section in the inner tube 4 .

[0072] In a more preferred embodiment, the sealing flange is further connected with a second process gas pipe joint 9 to introduce the second process gas; accordingly, the inner cover surface of the sealing flange is provided with a gas outlet 5. The second process gas is mainly an inert gas such as nitrogen, which does not participate in the reaction and mainly serves to form compressed gas, which directly penetrates from, for example, a water-cooled flange 6 to avoid the gas participating in the reaction from concentrating upward and suppress the influence of thermal buoyancy.

[0073] In addition, the length of the nested tubes makes the gas homogenizing part 1 at a suitable depth in the reaction chamber, and the inert gas such as nitrogen used as the compressed gas can more effectively make the state of the reaction gas in the reaction zone relatively stable. In particular, nitrogen has a relatively small density and is easier to be configured as a compressed gas.

[0074] Furthermore, a sealing gas homogenizing cavity is formed in the sealing flange for homogenizing the second process gas; Correspondingly, the air outlets 5 are distributed on the inner cover surface corresponding to the sealing air uniforming cavity; The second process gas pipe joint 9 is connected to the sealing gas uniforming cavity.

Claims

1. A vertical MOCVD gas homogenizing device, characterized in that: include: A cover flange is provided with a central hole and has an inner cover surface and an outer cover surface based on the cover; An inner tube passes through the central hole, wherein at least the outer diameter of the inner tube that matches the central hole is smaller than the diameter of the central hole, so as to form a flow gap between the inner tube and the wall of the central hole, and the inner tube provides an inner flow channel accordingly; A sleeve is sealed and connected to the inner cover surface of the sealing flange and sleeved outside the inner tube to form an outer flow channel communicating with the flow gap between the sleeve and the inner tube, and the overhanging end of the sleeve has an upper plate; An MO source pipe joint connected to the inner pipe to provide an MO source to the inner flow channel; a first process gas pipe joint connected to the central hole to provide a first process gas to the outer flow channel; The middle plate is connected to the lower side of the upper plate, and an upper uniform air cavity communicating with the outer flow channel is formed between the middle plate and the upper plate, and seat holes are distributed on the middle plate; The air distribution pipes are installed in the seat holes in a one-to-one correspondence and extend downward; as well as The lower plate is connected to the lower side of the middle plate, and a lower air-distributing cavity connected to the inner flow channel is formed between the lower plate and the middle plate; the lower plate is a porous plate, and some holes on the lower plate are used as through holes for the air distribution pipe to pass through.

2. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The length of the sleeve extending downward from the sealing flange is 0.72 to 0.80 times the diameter of the reaction chamber.

3. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The upper plate, the lower plate and the middle plate are connected by flanges; Correspondingly, the upper plate has an upper flange extending downward to form an upper air-distributing cavity side wall, and the lower plate has a lower flange extending upward to form a lower air-distributing cavity side wall.

4. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The air distribution duct head passes downward from the lower plate to expose the air distribution head, and the length of the air distribution head is 4 to 6 times the inner diameter of the air distribution duct.

5. The vertical MOCVD gas homogenizing device according to claim 1 or 4, characterized in that: The diameter of the air-distributing holes on the lower plate for air distribution is 0.5 to 0.7 times the diameter of the inner hole of the air distribution pipe; The air holes are arranged around the air distribution duct.

6. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The upper end of the sleeve is provided with a connecting flange, so as to be connected to the inner cover surface of the sealing flange through the flange connection; The axis of the connecting flange is collinear with the axis of the central hole; An outer barrel sleeved on the inner tube is connected to the outer end of the central hole, a gas supply cavity is formed between the outer barrel and the inner tube, and one side of the outer barrel is connected to the first process gas pipe joint; The bottom of the outer barrel is correspondingly used for sealing the upper end of the outer barrel body.

7. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The inner tube comprises a first inner tube section and a second inner tube section connected to each other, wherein the first inner tube section is used to connect to the reaction chamber from the outside and is partially located in the sleeve; Most of the second inner tube section is located in the sleeve, and the end exposed downward relative to the sleeve is used for connecting the inner flow channel with the lower uniform air cavity.

8. The vertical MOCVD gas homogenizing device according to claim 7, characterized in that: The second inner pipe section is connected to the casing through a plurality of radial connecting plates for heat exchange; Correspondingly, the outer surface of the sleeve section that is used to cooperate with the second inner pipe section is provided with heat exchange fins.

9. The vertical MOCVD gas homogenizing device according to claim 1, characterized in that: The sealing flange is also connected to a second process gas pipe joint for introducing the second process gas; Correspondingly, an air outlet is provided on the inner cover surface of the sealing flange.

10. The vertical MOCVD gas homogenizing device according to claim 9, characterized in that: A sealing gas homogenizing cavity is formed in the sealing flange for homogenizing the second process gas; Correspondingly, the air outlets are distributed on the inner cover surface corresponding to the sealing air uniforming cavity; The second process gas pipe joint is connected to the sealing gas uniforming cavity.

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