Rotating-speed-adjustable carrying disc rotating system and method and epitaxial furnace

Abstract

The invention relates to the technical field of epitaxial growth, and particularly provides a rotating-speed-adjustable carrying disc rotating system and method and an epitaxial furnace, and the system comprises an upper half-moon graphite cavity, a lower half-moon graphite cavity, an upper half-moon graphite cavity and a lower half-moon graphite cavity, a cavity and a rotary air passage are arranged in the lower half-moon graphite cavity; a tray; the axis of the transmission paddle shaft is staggered with the air inlet channel of the rotating air channel; a plurality of transmission paddles; a plurality of speed measurement blades; a rotating gas supply assembly; a rotating speed measuring assembly; the controller is used for controlling the rotating gas supply assembly to supply rotating gas into the rotating gas channel during epitaxial growth, and adjusting the flow of the rotating gas supplied into the rotating gas channel by the rotating gas supply assembly according to the rotating speed information of the carrying disc and a preset rotating speed until the rotating speed information of the carrying disc is the same as the preset rotating speed; the system can solve the problems that the cleanliness of a reaction cavity is reduced and the defects of an epitaxial layer growing on an epitaxial wafer are increased due to the fact that graphite dust generated when air flotation gas etches a graphite cavity in the next half month enters the reaction cavity, and the rotating speed of a loading disc is accurately controlled.

Description

Technical Field

[0001] The present application relates to the technical field of epitaxial growth, and in particular to a carrier rotation system and method with adjustable speed, and an epitaxial furnace. Background Art

[0002] In order to make the epitaxial layer grow uniformly on the epitaxial wafer, the related technology needs to set a flotation gas path connected to the reaction chamber in the lower half of the graphite cavity, and drive the carrier carrying the epitaxial wafer to float and rotate by directly supplying flotation gas into the reaction chamber through the flotation gas path. During the epitaxial growth process, the temperature in the reaction chamber can reach 1600°C, and the flotation gas will etch the lower half of the graphite cavity at high temperature, and the graphite dust generated by the etching will enter the reaction chamber. Therefore, the related technology has the problem that the graphite dust generated when the flotation gas etches the lower half of the graphite cavity enters the reaction chamber, resulting in a decrease in the cleanliness of the reaction chamber, and the graphite dust entering the reaction chamber adheres to the surface of the epitaxial wafer, resulting in an increase in the defects of the epitaxial layer grown on the epitaxial wafer, thereby resulting in a decrease in the yield of epitaxial growth. In addition, the related technology also has the problem that the rotation speed of the carrier cannot be accurately controlled because the flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the cavity.

[0003] There is no effective technical solution to the above problems. It should be noted that the above information disclosed in this section is only used to understand the background of the present invention, and therefore may contain information that does not constitute prior art. Summary of the invention

[0004] The purpose of the present application is to provide a carrier rotation system, method and epitaxial furnace with adjustable speed, which can effectively solve the problem of graphite dust generated when flotation gas etches the lower half of the graphite cavity into the reaction chamber, resulting in a decrease in the cleanliness of the reaction chamber and an increase in defects in the epitaxial layer grown on the epitaxial wafer, and can accurately control the speed of the carrier.

[0005] In a first aspect, the present application provides a carrier plate rotation system with adjustable speed, comprising: Upper half of the graphite cavity; The lower half-moon graphite cavity forms a reaction cavity with the upper half-moon graphite cavity. A cavity and a rotating airway are arranged in the lower half-moon graphite cavity. A velocity measuring hole is arranged on the lower half-moon graphite cavity. The cavity is located below the reaction cavity, and the rotating airway is located between the cavity and the reaction cavity. A carrier plate, located in the reaction chamber, for carrying the epitaxial wafer; The transmission propeller shaft is rotatably mounted on the lower half-moon graphite cavity, its axis is staggered from the air inlet of the rotating airway, and its top surface is in contact with the carrier plate limit position; A plurality of transmission blades are located in the rotating airway and are arranged in a circumferential array on the transmission blade shaft; A plurality of speed measuring blades are located in the cavity and are arranged in a circumferential array on the propeller shaft; A rotating gas supply assembly, connected to the air inlet end of the rotating airway, for supplying rotating gas into the rotating airway; The rotation speed measuring component is arranged outside the lower half of the graphite cavity and is used to measure the rotation speed of the speed measuring blade to obtain the rotation speed information of the carrier plate; The controller is used to control the rotating gas supply component to supply rotating gas into the rotating airway during epitaxial growth, so as to drive the transmission paddle shaft and the carrier to rotate through the transmission paddle blades, and adjust the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating airway according to the carrier rotation speed information and the preset rotation speed until the carrier rotation speed information is the same as the preset rotation speed.

[0006] The present application provides a carrier rotation system with adjustable speed, which can drive the transmission blades, the transmission blade shaft and the carrier to rotate synchronously by supplying rotating gas into the rotating airway using a rotating gas supply component. Since the present application does not need to drive the carrier to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity, the present application can effectively solve the problem that the cleanliness of the reaction chamber is reduced due to the graphite dust generated when the flotation gas etches the lower half of the graphite cavity and enters the reaction chamber, and the defects of the epitaxial layer grown on the epitaxial wafer increase due to the graphite dust entering the reaction chamber adhering to the surface of the epitaxial wafer, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating airway according to the carrier speed information and the preset speed, the present application can also effectively solve the problem that the rotation speed of the carrier cannot be accurately controlled because the air flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the cavity.

[0007] Optionally, the transmission paddle shaft and the carrier plate are limited and abutted against each other through a polygonal sleeve structure.

[0008] This technical solution is equivalent to avoiding the situation where the carrier plate slips under the action of inertia when the rotation speed changes due to the transmission paddle shaft and the carrier plate not being fixedly connected by means of a limited interference between the transmission paddle shaft and the carrier plate through a polygonal sleeve structure, thereby effectively improving the consistency of the rotation speeds of the transmission paddle shaft and the carrier plate, and further effectively improving the accuracy of adjusting the rotation speed of the carrier plate.

[0009] Optionally, the polygonal socket structure includes a regular hexagonal groove, which is arranged on the bottom surface of the carrier plate, and the shape of the top of the transmission paddle shaft matches the shape of the regular hexagonal groove. The top of the transmission paddle shaft is located in the regular hexagonal groove and is gap-connected with the regular hexagonal groove.

[0010] Optionally, a first groove is provided on the lower half-moon graphite cavity, the top of the transmission propeller shaft is located in the first groove and there is a gap between its side and the side of the first groove, and the supporting surface of the transmission propeller shaft is the surface of the transmission propeller shaft that contacts the inner bottom wall of the rotating airway.

[0011] Since the top of the transmission paddle shaft of the technical solution is located in the first groove and there is a gap between its side and the side of the first groove, that is, the top of the transmission paddle shaft of the technical solution does not contact the lower half-moon graphite cavity, that is, the technical solution can effectively avoid the situation in which the lower half-moon graphite cavity in contact with the top of the transmission paddle shaft is worn and graphite dust is generated during the rotation of the transmission paddle shaft due to the contact between the top of the transmission paddle shaft and the lower half-moon graphite cavity, and since the supporting surface of the transmission paddle shaft of the technical solution is the surface in contact with the inner bottom wall of the rotating airway in the transmission paddle shaft, that is, the supporting surface of the transmission paddle shaft is located in the rotating airway, the graphite dust generated by the rotation of the supporting surface of the transmission paddle shaft relative to the lower half-moon graphite cavity will flow out of the reaction chamber at the outlet end of the rotating airway under the action of the rotating gas, thereby effectively avoiding the situation in which the graphite dust generated by the rotation of the supporting surface of the transmission paddle shaft relative to the lower half-moon graphite cavity enters the reaction chamber, resulting in a decrease in the cleanliness of the reaction chamber and an increase in the defects of the epitaxial layer grown on the epitaxial wafer.

[0012] Optionally, a second groove is provided on the lower half-moon graphite cavity, and the carrier plate is located in the second groove and there is a gap between the carrier plate and the second groove.

[0013] Since the lower half-moon graphite cavity of the technical solution is provided with a second groove, the carrier plate is located in the second groove and there is a gap between the carrier plate and the second groove, that is, the carrier plate of the technical solution is not in direct contact with the lower half-moon graphite cavity, the technical solution can effectively avoid the situation in which the carrier plate and the lower half-moon graphite cavity in contact with the carrier plate are worn and graphite dust is generated during the rotation of the carrier plate due to direct contact between the carrier plate and the lower half-moon graphite cavity.

[0014] Optionally, the rotating disk carrier system with adjustable speed further comprises a process gas supply assembly, and the process gas supply assembly is used to supply process gas into the reaction chamber during epitaxial growth.

[0015] Optionally, the speed-adjustable carrier rotation system also includes an insulation component, which covers the outer sides of the upper and lower graphite cavities, and is provided with a speed measuring hole, a process gas inlet, a process gas outlet, a rotating gas inlet and a rotating gas outlet.

[0016] Optionally, the process of adjusting the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating gas channel according to the carrier rotation speed information and the preset rotation speed includes: Based on PID control, the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating gas channel is adjusted according to the carrier rotation speed information and the preset rotation speed.

[0017] In a second aspect, the present application further provides a method for rotating a carrier plate with an adjustable speed, which is applied to a carrier plate rotating system with an adjustable speed provided in the first aspect above, and the method for rotating a carrier plate with an adjustable speed comprises the following steps: S1. During epitaxial growth, the rotating gas supply assembly is controlled to supply rotating gas into the rotating airway, so as to drive the transmission paddle shaft and the carrier to rotate through the transmission paddles, and the flow rate of the rotating gas supplied by the rotating gas supply assembly into the rotating airway is adjusted according to the carrier rotation speed information and the preset rotation speed, until the carrier rotation speed information is the same as the preset rotation speed.

[0018] The present application provides a method for rotating a carrier with adjustable speed, which can drive the transmission blades, the transmission blade shaft and the carrier to rotate synchronously by supplying rotating gas into a rotating airway using a rotating gas supply component. Since the present application does not need to drive the carrier to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity, the present application can effectively solve the problem that the cleanliness of the reaction chamber is reduced due to the graphite dust generated when the flotation gas etches the lower half of the graphite cavity and enters the reaction chamber, and the defects of the epitaxial layer grown on the epitaxial wafer increase due to the graphite dust entering the reaction chamber adhering to the surface of the epitaxial wafer, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating airway according to the carrier speed information and the preset speed, the present application can also effectively solve the problem that the rotation speed of the carrier cannot be accurately controlled because the air flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the cavity.

[0019] In a third aspect, the present application further provides an epitaxial furnace, which includes a carrier rotation system with adjustable speed provided in the first aspect above.

[0020] The present application provides an epitaxial furnace, which can drive the transmission blades, the transmission blade shaft and the carrier to rotate synchronously by supplying rotating gas into the rotating airway through a rotating gas supply assembly. Since the present application does not need to drive the carrier to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity, the present application can effectively solve the problem that the cleanliness of the reaction chamber is reduced due to the graphite dust generated when the flotation gas etches the lower half of the graphite cavity and enters the reaction chamber, and the defects of the epitaxial layer grown on the epitaxial wafer increase due to the graphite dust entering the reaction chamber adhering to the surface of the epitaxial wafer, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier by adjusting the flow rate of the rotating gas supplied by the rotating gas supply assembly into the rotating airway according to the carrier rotation speed information and the preset rotation speed, the present application can also effectively solve the problem that the rotation speed of the carrier cannot be accurately controlled because the air flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the chamber.

[0021] As can be seen from the above, the present application provides a carrier rotation system, method and epitaxial furnace with adjustable speed, which can drive the transmission blades, transmission paddle shaft and carrier to rotate synchronously by utilizing a rotating gas supply component to supply rotating gas into a rotating airway. Since the present application does not need to drive the carrier to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity, the present application can effectively solve the problem that the cleanliness of the reaction chamber is reduced due to the graphite dust generated when the flotation gas etches the lower half of the graphite cavity and enters the reaction chamber, and the graphite dust entering the reaction chamber adheres to the surface of the epitaxial wafer, resulting in an increase in the defects of the epitaxial layer grown on the epitaxial wafer, thereby effectively improving the yield of epitaxial growth. Since the present application can accurately control the speed of the carrier by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating airway according to the carrier speed information and the preset speed, the present application can also effectively solve the problem that the speed of the carrier cannot be accurately controlled due to the fact that the air flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of a carrier plate rotating system with adjustable speed provided in an embodiment of the present application.

[0023] Figure 2 A schematic structural diagram of a rotating disk carrier system with adjustable speed provided in an embodiment of the present application, which does not include a speed measurement component.

[0024] Figure 3 For along Figure 2 Schematic diagram of the cross-sectional structure of the AA section line.

[0025] Figure 4For along Figure 2 Schematic diagram of the cross-sectional structure of the BB section line.

[0026] Figure 5 A schematic diagram of the structure of the carrier plate and the transmission propeller shaft provided in an embodiment of the present application.

[0027] Figure 6 A control relationship diagram of a carrier rotation system with adjustable speed provided in an embodiment of the present application.

[0028] Figure numerals: 1, lower half of the graphite cavity; 2, cavity; 3, rotating airway; 4, upper half of the graphite cavity; 5, reaction chamber; 6, carrier plate; 7, transmission paddle shaft; 8, transmission blade; 9, speed measuring blade; 10, rotating gas supply assembly; 11, speed measurement assembly; 12, controller; 13, regular hexagonal groove; 14, process gas supply assembly; 15, insulation assembly. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0030] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0031] First, as Figure 1-Figure 6 As shown, the present application provides a carrier plate rotating system with adjustable speed, which comprises: Upper half moon graphite cavity 4; The lower half-moon graphite cavity 1 and the upper half-moon graphite cavity 4 form a reaction cavity 5. The lower half-moon graphite cavity 1 is provided with a cavity 2 and a rotating airway 3. The lower half-moon graphite cavity 1 is provided with a velocity measuring hole. The cavity 2 is located below the reaction cavity 5, and the rotating airway 3 is located between the cavity 2 and the reaction cavity 5. A carrier plate 6 is located in the reaction chamber 5 and is used to carry the epitaxial wafer; The transmission propeller shaft 7 is rotatably mounted on the lower half-moon graphite cavity 1, its axis is staggered from the air inlet of the rotating airway 3, and its top surface is in contact with the carrier plate 6; A plurality of transmission blades 8 are located in the rotating airway 3 and are arranged in a circular array on the transmission blade shaft 7; A plurality of speed measuring blades 9 are located in the cavity 2 and arranged in a circular array on the transmission propeller shaft 7; A rotating gas supply assembly 10, connected to the air inlet end of the rotating airway 3, for supplying rotating gas into the rotating airway 3; The rotation speed measuring component 11 is arranged outside the lower half-moon graphite cavity 1 and is used to measure the rotation speed of the speed measuring blade 9 to obtain the rotation speed information of the carrier plate; The controller 12 is used to control the rotating gas supply component 10 to supply rotating gas into the rotating gas channel 3 during epitaxial growth, so as to drive the transmission paddle shaft 7 and the carrier 6 to rotate through the transmission paddle blades 8, and adjust the flow rate of the rotating gas supplied by the rotating gas supply component 10 into the rotating gas channel 3 according to the carrier rotation speed information and the preset rotation speed until the carrier rotation speed information is the same as the preset rotation speed.

[0032] The material of the lower half-moon graphite cavity 1 and the upper half-moon graphite cavity 4 of this embodiment is preferably high-purity graphite. The lower half-moon graphite cavity 1 and the upper half-moon graphite cavity 4 of this embodiment are both arranged in a reaction chamber, and the lower half-moon graphite cavity 1 is provided with a cavity 2 and a rotating airway 3. The upper half-moon graphite cavity 4 of this embodiment can be an existing upper half-moon graphite cavity 4, and the upper half-moon graphite cavity 4 is located above the lower half-moon graphite cavity 1. The upper half-moon graphite cavity 4 is preferably connected to the lower half-moon graphite cavity 1 through a side support, and the upper half-moon graphite cavity 4 and the lower half-moon graphite cavity 1 form a reaction chamber 5. The carrier plate 6 of this embodiment can be an existing carrier plate 6, and the carrier plate 6 is used to carry the epitaxial wafer that needs to be epitaxially grown, and the carrier plate 6 is located in the reaction chamber 5. The transmission paddle shaft 7 of this embodiment is rotatably mounted on the lower half-moon graphite cavity 1, that is, the transmission paddle shaft 7 can rotate relative to the lower half-moon graphite cavity 1, and the top surface of the transmission paddle shaft 7 is limitedly in conflict with the carrier plate 6. The number of transmission blades 8 of this embodiment is multiple, and the number of transmission blades 8 of this embodiment is preferably 6, and the multiple transmission blades 8 are all located in the rotating airway 3 and are circumferentially arrayed on the transmission paddle shaft 7. The number of speed measuring blades 9 of this embodiment is multiple, and the number of speed measuring blades 9 of this embodiment is preferably 2, and the multiple speed measuring blades 9 are all located in the cavity 2 and are circumferentially arrayed on the transmission paddle shaft 7.The rotating gas supply assembly 10 of this embodiment preferably includes a rotating gas storage assembly (which can be replaced by a rotating gas generating assembly), a mass flow controller and a gas pipeline. The rotating gas storage assembly is connected to the air inlet end of the rotating airway 3 through the gas pipeline. The mass flow controller is arranged on the gas pipeline. This embodiment can supply rotating gas to the rotating airway 3 by opening the mass flow controller. This embodiment can also use the mass flow controller to adjust the flow rate of the rotating gas supplied to the rotating airway 3. The rotating gas of this embodiment preferably includes an inert gas (such as argon) and / or a carrier gas. Even in a high temperature environment, the rotating gas of this embodiment will not cause etching to the lower half of the graphite cavity 1. It should be understood that since the axis of the transmission propeller shaft 7 is staggered with the air inlet of the rotating airway 3, when the rotating gas supply assembly 10 supplies rotating gas to the rotating airway 3, the transmission blades on both sides of the transmission propeller shaft 7 8 is subjected to uneven force, so when the rotating gas supply component 10 supplies rotating gas into the rotating airway 3, the transmission blade 8 and the transmission blade shaft 7 will rotate relative to the lower semi-lunar graphite cavity 1, and because the top surface of the transmission blade shaft 7 is in limit conflict with the carrier plate 6, when the transmission blade shaft 7 rotates relative to the lower semi-lunar graphite cavity 1, the carrier plate 6 will rotate with the transmission blade shaft 7, that is, this embodiment can drive the transmission blade shaft 7 and the carrier plate 6 to rotate by the transmission blade 8 by utilizing the rotating gas supply component 10 to supply rotating gas into the rotating airway 3, and because the magnitude of the driving force exerted on the transmission blade 8 is positively correlated with the flow rate of the rotating gas supplied by the rotating gas supply component 10 into the rotating airway 3, and the magnitude of the driving force exerted on the transmission blade shaft 7 is positively correlated with the rotation speed of the transmission blade shaft 7, therefore, this embodiment can adjust the rotation speed of the carrier plate 6 by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component 10 into the rotating airway 3. The speed measuring component 11 of this embodiment is preferably a through-beam photoelectric sensor. The speed measuring component 11 is arranged outside the reaction chamber. The speed measuring component 11 is used to measure the speed of the speed measuring blade 9 through the speed measuring hole. Since the speed measuring blades 9 of this embodiment are arranged in a circular array on the transmission paddle shaft 7, the speed measuring blade 9 of this embodiment rotates synchronously with the transmission paddle shaft 7 and the transmission paddle shaft 7, and the carrier 6, that is, the speed of the speed measuring blade 9 can reflect the speed of the carrier 6. Therefore, this embodiment can obtain the speed information of the carrier by measuring the speed of the speed measuring blade 9 by using the speed measuring component 11. Taking the speed measuring component 11 as a through-beam photoelectric sensor as an example, the principle of the speed measuring component 11 of this embodiment measuring the speed of the speed measuring blade 9 is as follows: since the rotation period of the speed measuring blade 9 is related to the speed of the speed measuring blade 9, and when the speed measuring blade 9 rotates, the speed measuring blade 9 will periodically block the photoelectric signal emitted by the through-beam photoelectric sensor, therefore, this embodiment can calculate the speed period of the speed measuring blade 9 according to the blocking period of the photoelectric signal, and calculate the speed of the speed measuring blade 9 according to the speed period of the speed measuring blade 9.It should also be understood that, since the material of the lower half-moon graphite cavity 1 of this embodiment is high-purity graphite, and high-purity graphite has good self-lubricating properties, the transmission propeller shaft 7 of this embodiment does not need to be installed on the lower half-moon graphite cavity 1 through a bearing.

[0033] The controller 12 of this embodiment is electrically connected to the rotating gas supply component 10 and the speed measuring component 11. The controller 12 of this embodiment can control the rotating gas supply component 10 to supply rotating gas into the rotating gas channel 3 during epitaxial growth, so as to drive the transmission blade 8 to drive the transmission blade shaft 7 and the carrier 6 to rotate, and adjust the flow rate of the rotating gas supplied by the rotating gas supply component 10 to the rotating gas channel 3 according to the carrier speed information and the preset speed until the carrier speed information is the same as the preset speed. The preset speed of this embodiment is a value preset by those skilled in the art according to actual needs.

[0034] The present application provides a carrier rotation system with adjustable speed, which can drive the transmission blade 8, the transmission blade shaft 7 and the carrier 6 to rotate synchronously by supplying rotating gas into the rotating airway 3 by the rotating gas supply component 10. Since the present application does not need to drive the carrier 6 to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity 1, the present application can effectively solve the problem that the cleanliness of the reaction chamber 5 is reduced due to the graphite dust generated when the flotation gas etches the lower half of the graphite cavity 1 and enters the reaction chamber 5, and the defects of the epitaxial layer grown on the epitaxial wafer increase due to the graphite dust entering the reaction chamber 5 adhering to the surface of the epitaxial wafer, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier 6 by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component 10 to the rotating airway 3 according to the carrier speed information and the preset speed, the present application can also effectively solve the problem that the rotation speed of the carrier 6 cannot be accurately controlled due to the fact that the air flotation rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the cavity. In addition, the prior art can drive the carrier 6 to rotate by fixing the carrier 6 on the rotating shaft and driving the rotating shaft to rotate by a contact transmission structure (such as a transmission gear set, a chain drive or a synchronous belt drive). However, since the temperature in the reaction chamber can reach 1600° C. during the epitaxial growth process, and the contact transmission structure will fail at this temperature, the prior art has the problem that the carrier 6 cannot be driven to rotate due to the failure of the contact transmission structure during the epitaxial growth process. However, since the present application drives the carrier 6 by supplying rotating gas to the rotating gas channel 3 using the rotating gas supply assembly 10, the carrier 6 can be driven to rotate by the rotating gas supply assembly 10. The disk 6 rotates, that is, the present application is equivalent to using a non-contact transmission structure to drive the carrier 6 to rotate. Therefore, the present application can effectively solve the problem that the carrier 6 cannot be driven to rotate due to the failure of the contact transmission structure in the epitaxial growth process. Moreover, since the present application does not need to drive the carrier 6 to float and rotate by directly supplying flotation gas to the reaction chamber 5 through the flotation gas path, the present application can also effectively avoid the flotation gas used to drive the carrier 6 to float and rotate entering the reaction chamber 5, causing the flotation gas atmosphere in the reaction chamber 5 to be disturbed, thereby affecting the growth of the epitaxial layer.

[0035] In some preferred embodiments, the transmission paddle shaft 7 and the carrier plate 6 are limitedly in conflict through a polygonal sleeve structure. Specifically, the polygonal sleeve structure of this embodiment can be a polygonal protrusion (such as a triangular protrusion or a rectangular protrusion) arranged on the bottom surface of the carrier plate 6 and a polygonal groove arranged on the top of the transmission paddle shaft 7 and matching the polygonal protrusion, the polygonal protrusion is located in the polygonal groove, when there is a difference between the rotation speed of the transmission paddle shaft 7 and the rotation speed of the carrier plate 6, the polygonal protrusion conflicts with the polygonal groove, and after the polygonal protrusion conflicts with the polygonal groove, the rotation speed of the transmission paddle shaft 7 is the same as the rotation speed of the carrier plate 6, that is, this embodiment is equivalent to avoiding the situation that the carrier plate 6 slips under the action of inertia when the rotation speed changes due to the fact that the transmission paddle shaft 7 and the carrier plate 6 are not fixedly connected by making the transmission paddle shaft 7 and the carrier plate 6 limitedly in conflict through the polygonal sleeve structure, thereby effectively improving the consistency of the rotation speeds of the transmission paddle shaft 7 and the carrier plate 6, and then effectively improving the accuracy of adjusting the rotation speed of the carrier plate 6.

[0036] In some preferred embodiments, the polygonal sleeve structure includes a regular hexagonal groove 13, which is arranged on the bottom surface of the carrier 6, and the shape of the top of the transmission paddle shaft 7 matches the shape of the regular hexagonal groove 13, and the top of the transmission paddle shaft 7 is located in the regular hexagonal groove 13 and is gap-connected with the regular hexagonal groove 13. This embodiment is equivalent to making the transmission paddle shaft 7 and the carrier 6 contact each other through the regular hexagonal sleeve structure, and since the regular hexagonal sleeve structure can withstand a large torque, this embodiment can further improve the consistency of the rotation speed of the transmission paddle shaft 7 and the carrier 6.

[0037] In some preferred embodiments, a first groove is provided on the lower semi-lunar graphite cavity 1, the top of the transmission paddle shaft 7 is located in the first groove and there is a gap between its side and the side of the first groove, and the supporting surface of the transmission paddle shaft 7 is the surface of the transmission paddle shaft 7 that contacts the inner bottom wall of the rotating airway 3. Since the top of the transmission paddle shaft 7 of this embodiment is located in the first groove and there is a gap between its side and the side of the first groove, that is, the top of the transmission paddle shaft 7 of this embodiment does not contact the lower half-moon graphite cavity 1, that is, this embodiment can effectively avoid the situation that the lower half-moon graphite cavity 1 in contact with the top of the transmission paddle shaft 7 is worn and graphite dust is generated during the rotation of the transmission paddle shaft 7 due to the contact between the top of the transmission paddle shaft 7 and the lower half-moon graphite cavity 1, and since the supporting surface of the transmission paddle shaft 7 of this embodiment is the surface in contact with the inner bottom wall of the rotating airway 3 in the transmission paddle shaft 7, that is, the supporting surface of the transmission paddle shaft 7 is located in the rotating airway 3, the graphite dust generated by the supporting surface of the transmission paddle shaft 7 when the lower half-moon graphite cavity 1 rotates will flow out of the reaction chamber at the outlet end of the rotating airway 3 under the action of the rotating gas, thereby effectively avoiding the situation that the graphite dust generated by the rotation of the supporting surface of the transmission paddle shaft 7 relative to the lower half-moon graphite cavity 1 enters the reaction chamber 5, resulting in a decrease in the cleanliness of the reaction chamber 5 and an increase in the defects of the epitaxial layer grown on the epitaxial wafer.

[0038] In some preferred embodiments, a second groove is provided on the lower half-moon graphite cavity 1, and the carrier plate 6 is located in the second groove and there is a gap between the carrier plate 6 and the second groove. Since the carrier plate 6 of this embodiment is located in the second groove and there is a gap between the carrier plate 6 and the second groove, that is, the carrier plate 6 of this embodiment is not in direct contact with the lower half-moon graphite cavity 1, this embodiment can effectively avoid the situation that the carrier plate 6 and the lower half-moon graphite cavity 1 in contact with the carrier plate 6 are worn and graphite dust is generated during the rotation of the carrier plate 6 due to the direct contact between the carrier plate 6 and the lower half-moon graphite cavity 1.

[0039] In some preferred embodiments, the rotating disk system with adjustable speed further includes a process gas supply assembly 14, which is used to supply process gas into the reaction chamber 5 during epitaxial growth. The process gas supply assembly 14 of this embodiment may be an existing process gas supply assembly 14, which is used to supply process gas into the reaction chamber 5 during epitaxial growth, and the process gas can chemically react on the surface of the epitaxial wafer to form an epitaxial layer on the epitaxial wafer.

[0040] In some preferred embodiments, the rotating system of the carrier with adjustable speed further includes a heat preservation component 15, which covers the outer sides of the upper half-moon graphite cavity 4 and the lower half-moon graphite cavity 1, and is provided with a speed measuring hole, a process gas inlet, a process gas outlet, a rotating gas inlet, and a rotating gas outlet. The heat preservation component 15 of this embodiment covers the outer sides of the upper half-moon graphite cavity 4 and the lower half-moon graphite cavity 1, and the heat preservation component 15 can reduce the heat loss of the upper half-moon graphite cavity 4 and the lower half-moon graphite cavity 1, so this embodiment can effectively improve the temperature stability in the reaction chamber 5 and reduce the heat that needs to be generated by the reaction chamber in the epitaxial growth process.

[0041] In some preferred embodiments, the process of adjusting the flow rate of the rotating gas supplied by the rotating gas supply assembly 10 to the rotating gas channel 3 according to the carrier rotation speed information and the preset rotation speed includes: The flow rate of the rotating gas supplied by the rotating gas supply assembly 10 into the rotating gas channel 3 is adjusted based on the PID control according to the carrier rotation speed information and the preset rotation speed.

[0042] This embodiment is equivalent to adjusting the rotation speed of the carrier plate 6 based on PID control. Since PID control has the advantages of good robustness and high adjustment accuracy, this embodiment can effectively improve the accuracy of adjusting the rotation speed of the carrier plate 6.

[0043] As can be seen from the above, the present application provides a carrier rotation system with adjustable speed, which can drive the transmission blade 8, the transmission blade shaft 7 and the carrier 6 to rotate synchronously by using the rotating gas supply component 10 to supply rotating gas into the rotating airway 3. Since the present application does not need to drive the carrier 6 to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity 1, the present application can effectively solve the problem of graphite dust generated by the flotation gas etching the lower half of the graphite cavity 1 entering the reaction chamber 5, resulting in a decrease in the cleanliness of the reaction chamber 5, and the problem of the following problems: The problem that graphite dust entering the reaction chamber 5 adheres to the surface of the epitaxial wafer and causes an increase in defects in the epitaxial layer grown on the epitaxial wafer is solved, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier 6 by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component 10 to the rotating airway 3 according to the carrier rotation speed information and the preset speed, the present application can also effectively solve the problem that the rotation speed of the carrier 6 cannot be accurately controlled because the air floating rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the chamber.

[0044] In a second aspect, the present application further provides a method for rotating a carrier plate with an adjustable speed, which is applied to a carrier plate rotating system with an adjustable speed provided in the first aspect above, and the method for rotating a carrier plate with an adjustable speed comprises the following steps: S1. During epitaxial growth, the rotating gas supply component 10 is controlled to supply rotating gas into the rotating gas channel 3 to drive the transmission paddle shaft 7 and the carrier 6 to rotate through the transmission paddle blades 8, and the flow rate of the rotating gas supplied by the rotating gas supply component 10 into the rotating gas channel 3 is adjusted according to the carrier rotation speed information and the preset rotation speed until the carrier rotation speed information is the same as the preset rotation speed.

[0045] An embodiment of the present application provides a method for rotating a carrier plate with an adjustable speed. The method for rotating a carrier plate with an adjustable speed provided by the embodiment is applied to a system for rotating a carrier plate with an adjustable speed provided by the first aspect. The principle of the method for rotating a carrier plate with an adjustable speed provided by the embodiment is the same as the principle of the system for rotating a carrier plate with an adjustable speed provided by the first aspect, and will not be discussed in detail here.

[0046] In a third aspect, the present application further provides an epitaxial furnace, which includes a carrier rotation system with adjustable speed provided in the first aspect above.

[0047] The present application provides an embodiment of an epitaxial furnace, which includes a carrier rotation system with adjustable speed provided by the first aspect. The principle of the epitaxial furnace provided by the embodiment is the same as the principle of the carrier rotation system with adjustable speed provided by the first aspect, and will not be discussed in detail here.

[0048] As can be seen from the above, the present application provides a carrier rotation system, method and epitaxial furnace with adjustable speed, which can drive the transmission blade 8, the transmission blade shaft 7 and the carrier 6 to rotate synchronously by using the rotating gas supply component 10 to supply rotating gas into the rotating airway 3. Since the present application does not need to drive the carrier 6 to rotate by air flotation rotation, and the rotating gas will not cause etching to the lower half of the graphite cavity 1, the present application can effectively solve the problem that the graphite dust generated when the flotation gas etches the lower half of the graphite cavity 1 enters the reaction chamber 5, resulting in a decrease in the cleanliness of the reaction chamber 5. And the problem of increased defects in the epitaxial layer grown on the epitaxial wafer due to the adhesion of graphite dust entering the reaction chamber 5 to the surface of the epitaxial wafer can be solved, thereby effectively improving the yield rate of epitaxial growth. Since the present application can accurately control the rotation speed of the carrier 6 by adjusting the flow rate of the rotating gas supplied by the rotating gas supply component 10 to the rotating airway 3 according to the carrier rotation speed information and the preset speed, the present application can also effectively solve the problem that the rotation speed of the carrier 6 cannot be accurately controlled because the air floating rotation is greatly affected by factors such as the air pressure, air flow rate and temperature in the chamber.

[0049] In the embodiments provided in the present application, it should be understood that, herein, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0050] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A rotating disc system with adjustable speed, characterized in that: The rotating disc system with adjustable speed includes: Upper half of the graphite cavity; The lower half-moon graphite cavity forms a reaction cavity with the upper half-moon graphite cavity, a cavity and a rotating airway are arranged in the lower half-moon graphite cavity, a velocity measuring hole is arranged on the lower half-moon graphite cavity, the cavity is located below the reaction cavity, and the rotating airway is located between the cavity and the reaction cavity; A carrier plate, located in the reaction chamber, for carrying the epitaxial wafer; A transmission propeller shaft is rotatably mounted on the lower half-moon graphite cavity, the axis of which is staggered from the air inlet of the rotating airway, and the top surface of which is in contact with the carrier plate; A plurality of transmission blades, located in the rotating airway and arranged in a circumferential array on the transmission blade shaft; A plurality of speed measuring blades, located in the cavity and arranged in a circumferential array on the propeller shaft; A rotating gas supply assembly, connected to the air inlet end of the rotating airway, for supplying rotating gas into the rotating airway; A rotation speed measuring component, arranged outside the lower half-moon graphite cavity, is used to measure the rotation speed of the speed measuring blade to obtain the rotation speed information of the carrier plate; A controller is used to control the rotating gas supply assembly to supply rotating gas into the rotating airway during epitaxial growth, so as to drive the transmission paddle shaft and the carrier to rotate through the transmission paddle blades, and to adjust the flow rate of the rotating gas supplied by the rotating gas supply assembly into the rotating airway according to the carrier rotation speed information and the preset rotation speed until the carrier rotation speed information is the same as the preset rotation speed.

2. The rotating disc system with adjustable speed according to claim 1, characterized in that: The transmission paddle shaft and the carrier plate are in limited contact with each other through a polygonal sleeve structure.

3. The rotating disc system with adjustable speed according to claim 2, characterized in that: The polygonal socket structure includes a regular hexagonal groove, which is arranged on the bottom surface of the carrier plate. The shape of the top of the transmission paddle shaft matches the shape of the regular hexagonal groove. The top of the transmission paddle shaft is located in the regular hexagonal groove and is gap-connected with the regular hexagonal groove.

4. The rotating disc system with adjustable speed according to claim 1, characterized in that: A first groove is provided on the lower half-moon graphite cavity, the top of the transmission propeller shaft is located in the first groove and there is a gap between its side and the side of the first groove, and the supporting surface of the transmission propeller shaft is the surface of the transmission propeller shaft that contacts the inner bottom wall of the rotating airway.

5. The rotating disc system with adjustable speed according to claim 1, characterized in that: A second groove is provided on the lower half-moon graphite cavity, and the carrier plate is located in the second groove and there is a gap between the carrier plate and the second groove.

6. The rotating disc system with adjustable speed according to claim 1, characterized in that: The rotating disk carrier system with adjustable speed further comprises a process gas supply assembly, and the process gas supply assembly is used to supply process gas into the reaction chamber during epitaxial growth.

7. The rotating disc system with adjustable speed according to claim 1, characterized in that: The speed-adjustable carrier rotation system also includes a heat preservation component, which covers the outer sides of the upper half-moon graphite cavity and the lower half-moon graphite cavity, and is provided with a speed measuring hole, a process gas inlet, a process gas outlet, a rotating gas inlet and a rotating gas outlet.

8. The rotating disc system with adjustable speed according to claim 1, characterized in that: The process of adjusting the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating gas channel according to the carrier rotation speed information and the preset rotation speed includes: Based on PID control, the flow rate of the rotating gas supplied by the rotating gas supply component to the rotating gas channel is adjusted according to the carrier rotation speed information and the preset rotation speed.

9. A method for rotating a carrier plate with adjustable speed, characterized in that: Applied in the rotating disk system with adjustable speed as claimed in any one of claims 1 to 8, the rotating disk method with adjustable speed comprises the following steps: S1. During epitaxial growth, the rotating gas supply assembly is controlled to supply rotating gas into the rotating airway, so as to drive the transmission paddle shaft and the carrier to rotate through the transmission paddle blades, and the flow rate of the rotating gas supplied by the rotating gas supply assembly into the rotating airway is adjusted according to the carrier rotation speed information and the preset rotation speed, until the carrier rotation speed information is the same as the preset rotation speed.

10. An epitaxial furnace, characterized in that: The epitaxial furnace comprises a carrier rotating system with adjustable speed as described in any one of claims 1-8.

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