CN216514255U

CN216514255U - Air supply conveying device and silicon carbide epitaxial growth equipment

Info

Publication number: CN216514255U
Application number: CN202123238211.3U
Authority: CN
Inventors: 吕立平
Original assignee: Hico Semiconductor Technology Suzhou Co ltd
Current assignee: Hico Semiconductor Technology Suzhou Co ltd
Priority date: 2021-12-21
Filing date: 2021-12-21
Publication date: 2022-05-13
Anticipated expiration: 2031-12-21

Abstract

The utility model discloses an air source conveying device, which comprises a partition plate and a guide plate, wherein the partition plate is provided with at least three ventilating units, each ventilating unit comprises at least one air hole, each air hole comprises a first opening arranged on the upper surface of the partition plate, a second opening arranged on the lower surface of the partition plate and a channel for communicating the first opening with the second opening, and the area of the second opening is larger than that of the first opening; the guide plate is provided with a plurality of guide holes, the lower surface of the partition plate is in butt joint with the guide plate, and the second opening of each air hole in the partition plate is communicated with the guide holes. The utility model also discloses silicon carbide epitaxial growth equipment. The utility model can realize the uniformity of airflow distribution, thereby improving the growth uniformity of products and improving the consistency of silicon carbide epitaxial growth.

Description

Air supply conveying device and silicon carbide epitaxial growth equipment

Technical Field

The utility model relates to the technical field of semiconductor manufacturing equipment, in particular to a gas source conveying device and silicon carbide epitaxial growth equipment.

Background

A Chemical Vapor Deposition (CVD) process is a method for preparing an epitaxial film by reacting different gases with each other at a high temperature. The flow rate of the gas in the reaction chamber affects the quality of the epitaxial film.

Most of the mainstream commercial semiconductor equipment in the current market adopts a vertical reaction cavity design, source gas required by deposition is conveyed into the reaction cavity through a spray head above the reaction cavity, a very thin detention layer is formed on the surface of a base after vertical airflow reaches a graphite base, reactants in the detention layer exceed the detention layer to be diffused to the surface of the substrate through diffusion, and nucleation and film growth are carried out on the surface of the substrate.

Silicon carbide (SiC) material is a third generation wide bandgap semiconductor material following the first generation semiconductor material silicon (Si) and the second generation semiconductor (gallium arsenide GaAs). At present, silicon carbide epitaxial materials are generally prepared by chemical CVD, and the depletion of growth gas in the diameter direction of an epitaxial layer in the growth process causes the growth rate of local points on the epitaxial layer and the variation of doping concentration along with the mixing uniformity of an air source and the flow rate and position of the air source, so that the non-uniformity of the silicon carbide epitaxial thickness and the doping concentration is caused. Therefore, the airflow is not uniform in the growth process of the silicon carbide epitaxial material, so that the amount of the gas flowing through the surface of the product is different, the difference is generated on each part of the grown product, the quality fluctuates, and the growth consistency of the product is influenced.

SUMMERY OF THE UTILITY MODEL

The technical problem to be solved by the embodiments of the present invention is to provide an air supply conveying device and silicon carbide epitaxial growth equipment, which can improve the growth uniformity of products and the uniformity of silicon carbide epitaxial growth.

In a first aspect of the present invention, there is provided an air source conveying device, including a partition plate and a flow guide plate, where the partition plate is provided with at least three air vent units, each air vent unit includes at least one air hole, each air hole includes a first opening disposed on an upper surface of the partition plate, a second opening disposed on a lower surface of the partition plate, and a channel communicating the first opening and the second opening, and an area of the second opening is larger than an area of the first opening; the baffle is provided with a plurality of flow guide holes, the lower surface of the baffle is in butt joint with the baffle, and the second opening of each air hole in the baffle is communicated with the flow guide holes.

In a possible implementation manner, when the first opening is an air inlet end of the air source conveying device, the flow guide hole is an air outlet end of the air source conveying device; when the first opening is the air outlet end of the air source conveying device, the flow guide hole is the air inlet end of the air source conveying device.

In a possible implementation manner, the air holes belonging to the same ventilation unit are distributed on the partition plate in a ring shape, and the corresponding ring shapes of the ventilation units have the same center.

In a possible implementation manner, the air holes belonging to the same ventilation unit are distributed on the partition plate in a circular shape, the corresponding circles of the ventilation units have the same center, and the center is coincident with the center of the partition plate.

In one possible implementation manner, the air holes belonging to the same ventilation unit are uniformly arranged on the partition board at intervals.

In a feasible implementation manner, the flow guide plate comprises a substrate and a base, wherein a first through hole is formed in the substrate, a second through hole is formed in the base, and the first through hole is communicated with the second through hole to form the flow guide hole; the substrate is arranged between the partition plate and the base, and the second opening of each air hole is communicated with the plurality of first through holes.

In a feasible implementation manner, a buffer channel is further arranged on the lower surface of the partition board, the buffer channel surrounds the ventilation unit on the outermost side of the partition board, and a side hole is formed in the side surface of the partition board and communicated with the buffer channel.

In one possible implementation, the gas source delivery device further comprises a temperature measuring hole penetrating through the partition plate and the base plate; the base of the guide plate is also provided with a supporting rib plate, and the supporting rib plate is arranged along the circumferential direction of the base.

In a feasible implementation manner, the gas source delivery device further includes a bushing, the bushing is sleeved outside the base, and the base and the bushing are made of quartz.

In a second aspect of the present invention, there is also provided silicon carbide epitaxial growth equipment, including the gas source delivery device of the first aspect.

The implementation of the utility model has the following beneficial effects:

the utility model designs an air source conveying device comprising a partition plate and a guide plate, wherein a plurality of groups of ventilation units are arranged on the partition plate, each group of ventilation units comprises at least one air hole, and a plurality of guide holes are arranged on the guide plate. At first, the air source is input through the air holes of different ventilation units on the partition plate, and then is more uniformly distributed through the flow guide holes on the flow guide plate, so that the output air flow is more uniformly distributed, the growth uniformity of the product can be improved, and the consistency of the epitaxial growth of the silicon carbide is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application and are not to be construed as limiting the application.

FIG. 1 is a schematic cross-sectional view of a gas delivery device according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a separator according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a substrate according to an embodiment of the utility model.

Fig. 4 is a schematic structural diagram of a base according to an embodiment of the present invention.

Reference numerals in the drawings: 1-partition plate, 10-ventilation unit, 101-first ventilation unit, 102-second ventilation unit, 103-third ventilation unit, 100-air hole, 11-first opening, 12-second opening, 13-buffer channel, 14-side hole, 15-temperature measurement hole, 2-flow guide plate, 20-flow guide hole, 201-first flow guide hole, 202-second flow guide hole, 203-third flow guide hole, 204-fourth flow guide hole, 21-substrate, 210-first through hole, 22-base, 220-second through hole, 221-support rib plate and 3-lining.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Silicon carbide epitaxial materials are generally prepared by a chemical CVD method, most of commercial semiconductor CVD equipment in the market at present adopts a vertical reaction cavity design, source gas required for deposition is conveyed into the reaction cavity through a spray head above the reaction cavity, a very thin detention layer is formed on the surface of a graphite base after vertical airflow reaches the graphite base, reactants in the detention layer cross the detention layer through diffusion and diffuse to the surface of a substrate, and nucleation and film growth are carried out on the surface of the substrate. However, the gas flow is not uniform in the growth process of the silicon carbide epitaxial wafer, so that the gas amount flowing through the surface of the product is different, the difference is generated on each part of the grown product, the quality fluctuates, and the growth consistency of the product is influenced.

Therefore, in order to solve the above-mentioned problem that the uniformity of the growth of the product is affected by the difference of the parts of the product grown due to the non-uniform air flow in the growth process of the silicon carbide epitaxial wafer, the present invention designs an air supply conveying device, as shown in fig. 1, the air supply conveying device includes a partition plate 1 and a flow guide plate 2, at least three ventilating units 10 are disposed on the partition plate 1, each ventilating unit 10 includes at least one air hole 100, each air hole 100 includes a first opening 11 disposed on the upper surface of the partition plate 1, a second opening 12 disposed on the lower surface of the partition plate 1 and a channel communicating the first opening 11 with the second opening 12, and the area of the second opening 12 is larger than the area of the first opening 11; the guide plate 2 is provided with a plurality of guide holes 20, the lower surface of the partition plate 1 is butted with the guide plate 2, and the second opening 12 of each air hole 100 on the partition plate 1 is communicated with the plurality of guide holes 20.

As shown in fig. 1 and 2, the air holes 100 belonging to the same aeration unit 10 are distributed in a ring shape on the partition plate 1, and the corresponding rings of the aeration units 10 have the same center. Further, the air holes 100 belonging to the same aeration unit 10 may be distributed in a circle on the separator 1, and the corresponding circles of the aeration units 10 have the same center, and the center coincides with the center O of the separator. The air holes 100 belonging to the same ventilating unit 10 are uniformly spaced on the partition plate 1. The lower surface of the partition board 1 is also provided with a buffer channel 13, the buffer channel 13 surrounds the ventilation unit 10 on the outermost side of the partition board 1, the side surface of the partition board 1 is provided with a side hole 14, and the side hole 14 is communicated with the buffer channel 13. In a possible implementation mode, the partition board 1 can be further provided with a temperature measuring hole 15, and the temperature measuring hole 15 is used for detecting the temperature in the equipment cavity outside the silicon carbide epitaxial wafer growth equipment, so that the temperature required by the growth of the silicon carbide epitaxial wafer can be adjusted timely.

In a possible implementation manner, as shown in fig. 1 and fig. 3, the baffle 2 may include a substrate 21 and a pedestal 22, the substrate 21 is provided with a first through hole 210, the pedestal 22 is provided with a second through hole 220, and the first through hole 210 is communicated with the second through hole 220 to form a baffle hole 20; the substrate 21 is disposed between the partition board 1 and the base 22, and the second opening 12 of each air hole 100 communicates with the plurality of first through holes 210. The base 22 is further provided with a support rib plate 221, and the support rib plate 221 is arranged along the circumferential direction of the base 22. The base plate 21 is also provided with a temperature measuring hole 15, and the temperature measuring hole 15 penetrates through the partition plate 1 and the base plate 21.

As shown in FIG. 1, the gas source delivering device further includes a liner 3, the liner 3 is sleeved outside the susceptor 22, and the susceptor 22 and the liner 3 are made of quartz. The reason is that the susceptor 22 and the liner 3 are used as the gas outlet end of the gas source conveying device and are directly connected with the inner part of the chamber of the growth equipment, and the reaction chamber of the CVD equipment can generate higher reaction temperature, so the quartz material of the susceptor 22 and the liner 3 can play the roles of heat insulation and protection for the whole gas source conveying device.

In one possible implementation manner, as shown in fig. 2, three ventilation units 10 are disposed on the partition plate 1, corresponding rings of the three ventilation units 10 have the same center O, that is, the three ventilation units 10 are respectively located on concentric circles using the center O of the partition plate 1 as a center, and the concentric circles where the three ventilation units 10 are located are, from inside to outside, the first ventilation unit 101, the second ventilation unit 102 and the third ventilation unit 103 in sequence using the center O of the partition plate 1 as a base point. The three aeration units 10 can respectively deliver different gas sources as different reaction gases, but of course, the three aeration units 10 can also respectively deliver the same reaction gas, or the three aeration units 10 can deliver the same reaction gas at intervals. That is, the first aeration unit 101 can deliver gas a, the second aeration unit 102 can deliver gas B, and the third aeration unit 103 can deliver gas C (wherein gas a, gas B, and gas C can represent different gas species, respectively); the first aeration unit 101, the second aeration unit 102, and the third aeration unit 103 may all deliver gas a, gas B, or gas C at the same time; the first aeration unit 101 and the third aeration unit 103 may deliver gas a, and the second aeration unit 102 may deliver gas B, and the like. Of course. In other possible implementations, four aeration units 10 or five aeration units 10 or more aeration units 10 are provided on the partition board 1. Namely, the aeration unit 10 of the gas source conveying device can be added to convey more kinds of reaction gas sources or more proportion and more amount of reaction gas according to the needs of the working reaction.

The vent of the vent unit may also have the following features: the air holes 100 belonging to the same aeration unit 10 are distributed annularly on the partition plate 1, and preferably, the air holes 100 belonging to the same aeration unit 10 are distributed circularly on the partition plate 1 and the air holes 100 belonging to the same aeration unit 10 are uniformly spaced on the partition plate 1. The number of the air holes 100 belonging to the same ventilation unit 10 is not less than 1, and when the center of the air hole 100 coincides with the center O of the partition plate, the number of the air holes 100 of the ventilation unit 10 in the group can be 1; when the centers of the air holes 100 do not coincide with the center O of the partition plate, that is, the circle corresponding to the ventilating unit 10 is a concentric circle with the center O of the partition plate as the center, then the air holes 100 belonging to the ventilating unit 10 are uniformly arranged on the partition plate 1 at intervals, that is, the number of the air holes 100 of the group of ventilating units 10 is greater than 1; as shown in fig. 2, the center of the air hole 100 of the first ventilation unit 101 coincides with the center O of the separator 1, and in this case, the first ventilation unit 101 includes 1 air hole 100, that is, in this case, the first ventilation unit 101 is configured by 1 air hole 100 at the center; and the air holes 100 of the second ventilation unit 102 and the third ventilation unit 103 are uniformly arranged on a concentric circle with the center O of the partition board 1 as a circle center at intervals, as shown in fig. 2, the number of the air holes 100 of the second ventilation unit 102 is 2, and the air holes 100 are respectively arranged on a concentric circle with the center O of the partition board 1 as a circle center at intervals of 180 °, that is, the second ventilation unit 102 is formed by the center 2 air holes 100. The number of the air holes 100 of the third air passing unit 103 is 4, and the air holes are respectively arranged on a concentric circle with the center O of the partition plate 1 as the center at intervals of 90 °, that is, the third air passing unit 103 is formed by the center 4 air holes 100. Of course, the number of the air holes 100 of the second ventilation unit 102 may also be 3, and the air holes are respectively arranged on a concentric circle with the center O of the partition board 1 as the center of the circle at intervals of 120 °; the number of the air holes 100 of the third ventilation unit 103 is 5, and the air holes are respectively arranged on a concentric circle with the center O of the partition board 1 as the center of the circle at intervals of 72 degrees; by analogy with … …, the number of gas holes 100 of each aeration unit 10 can be arranged reasonably according to the actual needs of the reaction gas.

Further, each air hole 100 includes a first opening 11 provided on the upper surface of the separator 1, a second opening 12 provided on the lower surface of the separator 1, and a passage communicating the first opening 11 and the second opening 12, the area of the second opening 12 being larger than the area of the first opening 11; first opening 11 is the inlet end of air supply conveyor, and the purpose that the area of second opening 12 is greater than the area of first opening 11 is in order to make the air supply cushion in the passageway of intercommunication first opening 11 and second opening 12 after the air supply is imported through first opening 11, and then carries out more even reposition of redundant personnel in getting into subsequent water conservancy diversion hole 20 with comparatively even velocity of flow again. As shown in fig. 1, when the structure of the air hole 100 is a stepped hole, it is satisfied that the area of the second opening 12 is larger than the area of the first opening 11; of course, various holes such as a trapezoidal hole and a tapered hole which satisfy that the area of the second opening 12 is larger than that of the first opening 11 can be provided, and the purpose of buffering after the air source enters the channel communicating the first opening 11 and the second opening 12 can be achieved.

In addition, as shown in fig. 1 and 2, a buffer channel 13 is provided on the lower surface of the separator 1, the buffer channel 13 surrounds the outermost aeration unit 10 on the separator 1, and a side surface of the separator 1 is provided with a side hole 14, the side hole 14 communicating with the buffer channel 13. I.e., the buffer channel 13 of the side hole 14 is circumferentially arranged along the circumference of the separator 1 and surrounds the respective air holes of the vent unit. The purpose of forming the side holes 14 and the buffer channels 13 is to inject purge gas, such as inert gas like argon, into the reaction cavity of the growth device before and after the reaction, so as to clean the residual reaction gas in the chamber, thereby ensuring the normal reaction of the working gas in the chamber.

The guide plate 2 comprises a substrate 21 and a base 22, wherein a first through hole 210 is formed in the substrate 21, a second through hole 220 is formed in the base 22, and the first through hole 210 is communicated with the second through hole 220 to form a guide hole 20; the substrate 21 is disposed between the partition board 1 and the base 22, and the second opening 12 of each air hole 100 communicates with the plurality of first through holes 210. As shown in fig. 3 and 4, the substrate 21 and the base 22 are respectively provided with first through holes 210 and second through holes 220 which are uniformly distributed, and the first through holes 210 and the second through holes 220 are communicated to form the diversion holes 20. As shown in fig. 3, since the air holes 100 of the first, second, and third

air vent units

101, 102, and 103 are respectively disposed on a concentric circle with the center O of the partition board 1 as the center, the air holes 20 corresponding to the first, second, and third

air vent units

101, 102, and 103 are also respectively formed in an annular band with the center O of the substrate 21 as the center, that is, the plurality of air vent holes 20 corresponding to the first air vent unit 101 on the substrate 21 are the first group of air vent holes 201, the plurality of air vent holes 20 corresponding to the second air vent unit 102 are the second group of air vent holes 202, and the plurality of air vent holes 20 corresponding to the third air vent unit 103 are the third group of air vent holes 203. A first group of flow guide holes 201 are communicated with a second opening of the air hole 100 of the first ventilation unit 101; a second group of guide holes 202 are communicated with a second opening of the air hole 100 of the second ventilation unit 102, and the second group of guide holes 202 form an annular belt surrounding the first group of guide holes 201; communicating with the second openings of the air holes 100 of the third ventilating unit 103 are third guide holes 203, and the third guide holes 203 are formed as an annular band surrounding the second guide holes 202. The plurality of guide holes 20 corresponding to the buffer channel 13 of the side hole 14 are a fourth group of guide holes 204, and the fourth group of guide holes 204 are formed to surround an annular band of the third group of guide holes 203. Each group of guiding holes 20 is uniformly arranged on the base plate 21 and the base 22 in a certain rule.

In a possible implementation manner, a support rib 221 may be further disposed on the base 22, and the support rib 221 is disposed along a circumferential direction of the base 22. The base plate 21 is also provided with a temperature measuring hole 15, and the temperature measuring hole 15 penetrates through the partition plate 1 and the base plate 21.

The embodiment of the present invention further provides a silicon carbide epitaxial growth apparatus with a gas source delivery device, and for the specific structure of the gas source delivery device, reference is made to the above embodiments, which are not described herein again. In a possible implementation manner, when the gas source conveying device of this embodiment is used for conveying gas into the silicon carbide epitaxial wafer growth apparatus (i.e., when gas is fed), the first opening 11 is a gas inlet end of the gas source conveying device, and the flow guide hole 20 is a gas outlet end of the gas source conveying device; when the gas source conveying device provided by the utility model is used as silicon carbide epitaxial wafer growth equipment to convey gas to the outside (namely, during air extraction), the first opening 11 is the air outlet end of the gas source conveying device, and the flow guide hole 20 is the air inlet end of the gas source conveying device. When the gas source conveying device is used for conveying gas into the silicon carbide epitaxial wafer growth equipment (namely, during gas inlet), different or same types of gas can be input through the gas holes 100 of the different ventilation units 10, and then flow guide holes 20 formed in the base plate 21 and the base 22 are used for conducting more uniform flow distribution, so that the flow rate of the gas is more uniform, and finally the gas enters the chamber of the growth equipment at a uniform flow rate to react, so that the silicon carbide epitaxial wafer with better product growth consistency is obtained. Similarly, when the gas source conveying device of this embodiment is used as the silicon carbide epitaxial wafer growth equipment and is used for conveying gas to the outside (i.e. during pumping), when the reaction is finished and the reaction gas is pumped out, the gas is pumped out from the chamber through the flow guide holes 20 formed in the substrate 21 and the base 22 at a more uniform flow rate, so that the gas quantity on the surface of the product is more uniform, and the silicon carbide epitaxial wafer with better uniformity in product growth is obtained.

By the gas source conveying device and the silicon carbide epitaxial growth equipment, gas sources can uniformly enter and be pumped out of the cavity of the equipment, and further reaction gas can be uniformly diffused to the surface of the substrate through diffusion, nucleates on the surface of the substrate and grows a film. The uniformity of airflow in the growth process of the silicon carbide epitaxial wafer is ensured, so that the amount of the gas flowing through the surface of the product is more uniform, the difference of each part of the grown product is reduced, and the uniformity of the growth of the product is more facilitated.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An air source conveying device is characterized by comprising a baffle plate and a flow guide plate,

the partition plate is provided with at least three ventilation units, each ventilation unit comprises at least one air hole, each air hole comprises a first opening arranged on the upper surface of the partition plate, a second opening arranged on the lower surface of the partition plate and a channel communicated with the first opening and the second opening, and the area of the second opening is larger than that of the first opening;

the baffle is provided with a plurality of flow guide holes, the lower surface of the baffle is in butt joint with the baffle, and the second opening of each air hole in the baffle is communicated with the flow guide holes.

2. The air supply delivery device of claim 1, wherein when the first opening is an air inlet end of the air supply delivery device, the diversion hole is an air outlet end of the air supply delivery device; when the first opening is the air outlet end of the air source conveying device, the flow guide hole is the air inlet end of the air source conveying device.

3. The air supply conveying device according to claim 1, wherein the air holes belonging to the same ventilating unit are distributed on the partition plate in a ring shape, and the corresponding ring shapes of the ventilating units have the same center.

4. The air supply conveying device according to claim 3, wherein the air holes belonging to the same ventilating unit are distributed on the partition in a circular shape, the corresponding circular shape of each ventilating unit has the same center, and the center coincides with the center of the partition.

5. The air supply conveying device according to claim 3 or 4, wherein the air holes belonging to the same ventilation unit are uniformly arranged on the partition plate at intervals.

6. The air supply delivery device of claim 1, wherein the baffle plate comprises a base plate and a base, the base plate is provided with a first through hole, the base is provided with a second through hole, and the first through hole and the second through hole are communicated to form the baffle hole; the substrate is arranged between the partition plate and the base, and the second opening of each air hole is communicated with the plurality of first through holes.

7. The air supply delivery device according to claim 1, wherein a buffer channel is further disposed on a lower surface of the partition, the buffer channel surrounds the outermost ventilation unit on the partition, and a side hole is disposed on a side surface of the partition, and the side hole is communicated with the buffer channel.

8. The gas source delivery device according to claim 6, further comprising a temperature sensing hole extending through the baffle plate and the base plate;

the base of the guide plate is also provided with a supporting rib plate, and the supporting rib plate is arranged along the circumferential direction of the base.

9. The gas source delivery device according to claim 6, further comprising a liner, wherein the liner is disposed outside the susceptor, and the susceptor and the liner are made of quartz.

10. An apparatus for epitaxial growth of silicon carbide, comprising the gas supply device according to any one of claims 1 to 9.