MOCVD reaction chamber and control method thereof

Abstract

The invention provides an MOCVD (Metal Organic Chemical Vapor Deposition) reaction chamber and a control method thereof. The reaction chamber comprises a vacuum cavity shell, a spraying head, a substrate bearing assembly, a heating assembly, a rotating assembly and a tail gas collecting and discharging device, the rotating assembly comprises a rotating assembly base, and the rotating assembly base achieves suspension supporting through the gas-magnetism combined effect and is driven by gas injection to rotate. The rotating component base is connected with the substrate bearing component through mutually matched conical surfaces to drive the substrate bearing component to synchronously rotate; the substrate bearing assembly comprises a substrate bearing disc used for bearing a substrate, and the edge of the substrate bearing disc is of a streamline structure. The tail gas collecting and discharging device is integrated on the vacuum cavity shell in an annular structure and located between the substrate carrying disc and the rotating assembly. The substrate bearing assembly is driven to suspend in the reaction chamber through the gas-magnetism combined effect, non-contact high-speed stable rotation is achieved through driving gas, meanwhile, tail gas can be guided to be extracted in the circumferential direction, the flow field stability is further improved, and the film growth uniformity is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor material growth, and more specifically to an MOCVD reaction chamber and its control method. Background Technology

[0002] Metal-organic chemical vapor deposition (MOCVD) is a key epitaxial technique for preparing III-V and II-VI compound semiconductors and nitride optoelectronic materials.

[0003] With the rapid development of display technology, higher requirements have been placed on the growth quality and uniformity of epitaxial materials. In high-end display applications, even slight variations in the thickness or composition of epitaxial wafers can cause device performance to deviate significantly from design specifications, thereby seriously affecting product yield and manufacturing costs.

[0004] Studies have shown that epitaxial uniformity (within and between furnace cycles) is affected by a variety of factors, with the structural design of the MOCVD reaction chamber playing a crucial role in addition to process parameters. The core mechanism lies in the fact that the reaction chamber structure directly influences the uniformity of the epitaxial film by controlling the vapor-deposited reaction boundary layer on the substrate surface. A sufficiently thin and highly uniform boundary layer is an important prerequisite for achieving high-quality, highly consistent epitaxial films.

[0005] Further research revealed that using a high-speed rotating carrier disk effectively enhances forced convection within the reaction chamber and generates a pumping effect, thereby improving the mixing uniformity of the reactant gases and smoothing local temperature and concentration gradients. This rotational motion also breaks up eddy structures in stagnant regions, suppressing natural convection driven by thermal buoyancy, resulting in more uniform and stable transport of reactant gases to the substrate surface. By combining the coordinated control of rotational speed, pressure, and gas flow rate, the stability of the gas flow and the uniformity of the substrate temperature field can be further improved, ultimately forming a thin and uniform reaction boundary layer, ensuring high-quality epitaxial growth.

[0006] Therefore, there is an urgent need for an MOCVD reaction chamber that can achieve high-speed and high-stability rotation of the substrate, effectively maintaining the uniformity of the gas flow field and temperature field during the rotation process, thereby ensuring the consistency of the epitaxial film in terms of thickness and composition, and meeting the stringent requirements for material uniformity in high-end display and other fields. Summary of the Invention

[0007] The purpose of this application is to provide an MOCVD reaction chamber and its control method, which can achieve high-speed and high-stability rotation of the substrate and effectively maintain the uniformity of the gas flow field and temperature field during the rotation process, thereby improving the uniformity of the epitaxial film in terms of thickness and composition and the overall quality.

[0008] In a first aspect, the present invention provides an MOCVD reaction chamber, comprising a vacuum chamber shell, a spray head, a substrate support assembly, a heating assembly, a rotating assembly, and a tail gas collection and exhaust device; The rotating component includes a rotating component base, which achieves levitation support through a combination of gas and magnetism and is driven to rotate by gas injection; the rotating component base and the substrate support component are connected by mutually cooperating conical surfaces, driving the substrate support component to rotate synchronously; The substrate carrier assembly includes a substrate carrier disk for supporting the substrate, and the edges of the substrate carrier disk have a streamlined structure; The exhaust gas collection and discharge device is integrated into the vacuum chamber housing in a ring structure and is located between the substrate carrier and the rotating assembly.

[0009] The MOCVD reaction chamber provided in this application utilizes a combined gas-magnetic effect to controllably suspend the substrate support assembly within the reaction chamber via a rotating component base. Furthermore, contactless, high-speed, and stable rotation is achieved through the injection of driving gas, which is beneficial for the growth of high-quality, highly uniform epitaxial films. Simultaneously, the streamlined edge design of the substrate carrier and the annular arrangement of the exhaust gas collection and discharge device between the substrate carrier and the rotating component guide the exhaust gas from epitaxial growth and the driving gas to be uniformly and smoothly extracted along the circumferential direction. This effectively avoids disturbances to the flow field within the reaction chamber caused by uneven exhaust, further enhancing flow field stability and improving film growth uniformity.

[0010] In some embodiments, the rotating assembly further includes a radial jetting device and a gas-magnetic combined support device integrated on the vacuum chamber housing, forming a groove. The rotating assembly base is housed in the groove and located above the gas-magnetic combined support device. The radial jetting device and the gas-magnetic combined support device have a gas equalization chamber and multiple jet holes communicating with the gas equalization chamber on their inner surfaces facing the rotating assembly base. Magnetic elements are respectively provided at the top of the gas-magnetic combined support device and the bottom of the rotating assembly base. It should be noted that, based on the pressure equalization effect of the gas equalization chamber, the outlet gas pressure of the jet holes can be made completely equal. Based on the throttling effect of the jet holes, the pressure energy of the high-pressure gas can be converted into the kinetic energy of the high-speed airflow. After the high-speed airflow impacts the rotating assembly base, it generates an axial load, causing the rotating assembly base and the gas-magnetic combined support device to separate, achieving mechanical contactless support for the rotating assembly and solving the problem that the maximum rotational speed of the rotating assembly is difficult to increase due to the limited maximum linear velocity of the mechanical bearing. By actively counteracting most of the gravity of the rotating component using magnetic repulsion, the load requirements of the air-magnetic combined support device are greatly reduced, enabling the system to achieve high-precision and high-response active control of the axial position of the rotating component by fine-tuning the air flow.

[0011] In some embodiments, a plurality of grooves are uniformly arranged along the circumferential direction on the radially outer and / or radially inner surfaces of the rotating component base; the grooves are arranged in a vertical, inclined, or herringbone pattern. It should be noted that when the grooves are vertical, the same rotational tangential force can be provided with a smaller jet flow rate, thereby reducing gas consumption. When the grooves are inclined, their inclination direction coordinates with the airflow injection direction of the corresponding driving gas nozzle to generate an upward axial component force during driving rotation, thereby reducing the film pressure and gas volume requirements. When the grooves are herringbone-shaped, their axial center is separated by an annular protrusion to form a local high-pressure zone in the central region when the driving airflow impacts, providing additional film stiffness and rotational stability.

[0012] In some embodiments, the radial jetting device includes a first radial jetting device and a second radial jetting device coaxially arranged. The first radial jetting device is sleeved on the outer periphery of the rotating component base, and the second radial jetting device is embedded in the inner periphery of the rotating component base. An air gap exists between each of the first and second radial jetting devices and the rotating component base. It should be noted that the coaxial design of the radial jetting devices and the rotating component base ensures that the high-pressure jet gas energy is efficiently and smoothly converted into the rotational mechanical energy of the rotating component base. Simultaneously, the inner and outer periphery design avoids asymmetric loads, local stall, and aerodynamic vibration, ensuring safe and reliable operation of the equipment. The air gaps between each of the first and second radial jetting devices and the rotating component base ensure that no hard contact or friction occurs between the devices.

[0013] In some embodiments, both the first radial jet device and the second radial jet device include: a gas flow controller, an air inlet pipe, a gas equalization chamber, and a plurality of jet holes equidistantly distributed on the circumference; the central axis of the jet holes is located in a plane parallel to the upper end face of the rotating component base, and is perpendicular to but does not intersect with the central axis of the rotating component base; the central axis of the jet hole of the first radial jet device has a first deflection angle θ1 with the normal direction of the inner surface of the first radial jet device, and the deflection direction of the first deflection angle θ1 is the same as or opposite to the preset rotation direction of the rotating component base, 30°≤θ1≤45°; the central axis of the jet hole of the second radial jet device has a first deflection angle θ2 with the normal direction of the outer surface of the second radial jet device, and the deflection direction of the second deflection angle θ2 is the same as or opposite to the preset rotation direction of the rotating component base, 30°≤θ2≤45°. It should be noted that, based on the symmetrical distribution of the jet nozzles, the radial forces generated by the jets are balanced, constraining the rotating component base radially and stably positioning it in the working position, enabling the rotating component base to rotate around the central axis or an axis parallel to it. Simultaneously, the ejected airflow cools the rotating component base, ensuring stable operation within a suitable temperature range. Since the deflection directions of the jet nozzles on the first and second radial jet devices are the same or opposite, the airflow forces can be added or differentiated according to actual needs. When the deflection directions of the jet nozzles on the first and second radial jet devices are the same, the effect of force addition can be achieved, realizing high-torque drive; when the deflection directions of the jet nozzles on the first and second radial jet devices are opposite, the effect of force differentiation can be achieved, realizing more precise speed regulation.

[0014] In some implementations, the jet orifices are divided into multiple groups, with each group's jet orifices connected to an independent airflow channel, which can be controlled individually. It should be noted that sensors can detect the air gap width at the corresponding position of each group of jet orifices in real time, and based on this feedback signal, the airflow rate of each group of jet orifices can be adjusted independently. Through this zoned control mechanism, the spatial attitude of the rotating component base can be actively adjusted, precisely controlling the concentricity and coaxiality between the rotating component base and the vacuum chamber shell.

[0015] In some embodiments, the upper surface of the gas-magnetic combined support device is provided with circumferentially uniformly distributed small air outlets, which are connected through a uniform air distribution cavity inside the gas-magnetic combined support device. When air exits through the outlets, a gas film is formed between the upper surface of the gas-magnetic combined support device and the lower surface of the rotating component base. It should be noted that when air exits through the outlets, a gas film is formed between the lower surface of the rotating component base and the upper surface of the gas-magnetic combined support device under the lifting effect of the airflow. This gas film is sufficient to support the weight of the entire rotating component (including the substrate carrier, quartz support, and rotating component base), achieving mechanical contactless support for the rotating component.

[0016] In some embodiments, a permanent magnet array is embedded in the bottom of the rotating component base; an electromagnetic coil element with at least three poles is embedded in the upper part of the air-magnetic combined support device. It should be noted that the magnitude and direction of the electromagnetic force of each pole of the electromagnetic coil can be adjusted independently. By adjusting the electromagnetic force of each pole, the magnitude and direction of the resultant force formed by the air-magnetic combined support device and the permanent magnet array in the rotating component base can be adjusted, thereby realizing the adjustment and control of the spatial position and attitude of the rotating component base.

[0017] In some implementations, the permanent magnet array is a Helbeck array. It should be noted that the Helbeck array can highly concentrate magnetic field energy on one side of the gas film (the strong magnetic field side), while the magnetic field on the other side (the weak magnetic field side) is significantly attenuated. This directional focusing magnetic circuit structure effectively suppresses stray magnetic fields, enhances the magnetic force between the electromagnetic coil and the permanent magnet array, and can reduce the amount of permanent magnets used and the amount of gas used in the gas-magnetic combined support device.

[0018] In some embodiments, the exhaust gas collection and discharge device is located 5mm-10mm below the edge of the substrate carrier. The inner wall of the exhaust gas collection and discharge device is provided with an annular groove and circumferentially distributed inlet and outlet through-holes. The top of the annular groove has a rounded corner transition. Both the inlet and outlet through-holes are connected to the exhaust gas collection chamber. The inlet through-hole is located inside the vacuum chamber shell, and the outlet through-hole is located outside the vacuum chamber shell. The sum of the cross-sectional areas of the inlet through-holes is equal to 0.9-1 times the sum of the cross-sectional areas of the outlet through-holes. It should be noted that when the exhaust gas collection and discharge device is 5-10mm below the substrate carrier, it can ensure that the upward and downward airflows are directly discharged after merging, and it can also ensure that the extraction of exhaust gas will not affect the airflow in the upper chamber of the reaction chamber. The annular groove on the inner wall of the exhaust gas collection device, the circumferentially distributed inlet and outlet through-holes, and the fact that the sum of the cross-sectional areas of the inlet through-holes is equal to 0.9-1 times the sum of the cross-sectional areas of the outlet through-holes, ensure that the reaction exhaust gas is uniformly extracted in the circumferential direction, avoiding adverse disturbances to the flow of reactant gases within the reaction chamber caused by uneven exhaust gas flow. The rounded corner transition at the top of the annular groove ensures that no eddies are generated near the exhaust gas outlet.

[0019] In some embodiments, the substrate carrier assembly further includes a quartz support member located below the substrate carrier plate. Upper concave conical surfaces with the smaller end on the upper side and the larger end on the lower side are provided on the lower end surface of the substrate carrier plate and the upper end surface of the quartz support member, and they are connected with each other in cooperation through the upper concave conical surfaces; the coefficient of thermal expansion of the substrate carrier plate is greater than that of the quartz support member, and in the horizontal direction, the quartz support member is located inside the substrate carrier plate. It should be noted that the conical surface connection with the substrate carrier plate with a larger coefficient of thermal expansion outside and the quartz support member with a smaller coefficient of thermal expansion inside can prevent the graphite part of the substrate carrier plate with a larger coefficient of thermal expansion from cracking the quartz part with a smaller coefficient of thermal expansion at high temperatures.

[0020] In some embodiments, upper concave conical surfaces with the smaller end on the upper side and the larger end on the lower side are provided on the lower end surface of the quartz support member and the upper end surface of the rotating component base, and they are connected with each other in cooperation through the upper concave conical surfaces; the coefficient of thermal expansion of the rotating component base is greater than that of the quartz support member, and in the horizontal direction, the quartz support member is located inside the rotating component base. It should be noted that the conical surface connection with the rotating component base with a larger coefficient of thermal expansion outside and the quartz support member with a smaller coefficient of thermal expansion inside can prevent the rotating component base with a larger coefficient of thermal expansion from cracking the quartz support member with a smaller coefficient of thermal expansion at high temperatures.

[0021] In some embodiments, the side surface of the substrate carrier plate is a conical surface with the upper part smaller and the lower part larger. The conical surface is transitioned to the upper surface of the substrate carrier plate through an outward convex fillet and to the lower surface through an inward concave fillet, forming a streamlined structure. The conical surface and the inner wall of the vacuum chamber housing together form a tapered pipe. The distance between the upper end of the conical surface and the inner wall of the vacuum chamber housing is twice the distance between the lower end of the conical surface and the inner wall of the vacuum chamber housing. It should be noted that the streamlined structure at the edge of the substrate carrier plate can effectively guide the downward airflow from the spray head and the upward airflow from the driving device, enabling them to smoothly converge at the edge of the carrier plate and stably transition to a laminar flow, thus avoiding the generation of eddy currents. The conical surface and the inner wall of the vacuum chamber housing together forming a tapered pipe can reduce the interference of the upward airflow on the vacuum chamber.

[0022] In some embodiments, the cross-section combination of the rotating component and the substrate carrier assembly forms a "冂" - shaped structure, and the central internal area enclosed by the "冂" - shaped structure is a non - rotating area. It should be noted that the driving and supporting devices and the heating component are decoupled in space, avoiding mutual interference, which enables the heater support to be designed with more mechanical support points, thereby effectively suppressing its thermal creep deformation in a high - temperature working environment, and further improving the thin - film growth quality.

[0023] In a second aspect, the present application provides a control method for the above - mentioned MOCVD reaction chamber, including: Start the rotating component to make the rotating component base suspended under the combined action of gas and magnetism; The jet of driving gas causes the rotating component base to rotate and drives the substrate-supporting component to rotate synchronously. The heating assembly is activated to heat the substrate carrier until the preset temperature is reached; The MO source is injected from the spray head into the reaction chamber for epitaxial growth; The exhaust gas from epitaxial growth and the driving gas exhaust gas smoothly converge under the guidance of the streamlined structure at the edge of the substrate carrier disk, and stably transition to laminar flow before being discharged from the reaction chamber by the exhaust gas collection and discharge device.

[0024] The MOCVD reaction chamber control method provided in this application utilizes a gas-magnetic combined effect to controllably suspend the substrate support assembly within the reaction chamber via a rotating component base. Then, non-contact, high-speed, and stable rotation is achieved through the injection of driving gas, which is beneficial for the growth of high-quality, highly uniform epitaxial films. Simultaneously, the exhaust gas from epitaxial growth and the driving gas exhaust gas smoothly converge under the guidance of the streamlined structure at the edge of the substrate carrier disk, and stably transition into laminar flow, effectively avoiding the generation of eddies and ensuring the stability and uniformity of the reaction gas at the wafer surface boundary layer, thereby achieving high-quality, highly uniform thin film epitaxial growth. Attached Figure Description

[0025] Figure 1 This is a cross-sectional schematic diagram of an MOCVD reaction chamber according to an embodiment of this application.

[0026] Figure 2 This is a top view of the rotating component in an embodiment of this application.

[0027] Figure 3 This is a schematic diagram of the structure of the first radial jet device in the embodiments of this application.

[0028] Figure 4 This is a cross-sectional schematic diagram of the first radial jet device in an embodiment of this application.

[0029] Figure 5 This is a schematic diagram of the structure of the second radial jet device in the embodiments of this application.

[0030] Figure 6 This is a cross-sectional schematic diagram of the second radial jet device in an embodiment of this application.

[0031] Figure 7 This is a cross-sectional schematic diagram of the jet hole grouping in the radial jet device in an embodiment of this application.

[0032] Figure 8 This is a schematic diagram of the air-magnetic combined support device in the embodiments of this application.

[0033] Figure 9 This is a cross-sectional schematic diagram of the air-magnetic combined support device in the embodiments of this application.

[0034] Figure 10 This is a schematic diagram of the combination of the air-magnetic joint support device and the rotating component base in the embodiments of this application.

[0035] Figure 11 This is a schematic diagram of the structure in which the grooves of the rotating component base are arranged vertically in an embodiment of this application.

[0036] Figure 12 This is a schematic diagram of the structure in which the grooves of the rotating component base are arranged in an inclined manner in an embodiment of this application.

[0037] Figure 13 This is a schematic diagram of the structure in which the grooves of the rotating component base are arranged in a fishbone pattern in an embodiment of this application.

[0038] Figure 14 This is a schematic diagram of the exhaust gas device in the embodiments of this application.

[0039] Figure 15 This is a cross-sectional schematic diagram of the quartz support member in the embodiments of this application.

[0040] Figure 16 This is a schematic diagram of the substrate carrier disk in an embodiment of this application.

[0041] Figure 17 A cross-sectional schematic diagram of the edge of the substrate carrier disk is provided for this application.

[0042] Figure 18 This is a schematic diagram of the gas flow direction of the streamlined structure at the edge of the substrate disk in the embodiments of this application.

[0043] In the figure: 1-spray head, 2-vacuum chamber shell, 3-exhaust gas collection and exhaust device, 4-rotating component, 5-substrate support component, 6-heating component.

[0044] 21-Upper sidewall of vacuum chamber, 22-Lower sidewall of vacuum chamber, 23-Lower outer bottom plate of vacuum chamber, 24-Bottom plate of vacuum chamber, 25-Inner bottom plate of lower vacuum chamber.

[0045] 31-Inlet port, 32-Exhaust gas collection chamber, 33-Outlet port, 34-Suction pipe, 35-Vacuum pump, 36-Annular groove.

[0046] 41-First radial jet device, 42-Air-magnetic combined support device, 43-Second radial jet device, 44-Rotating component base.

[0047] 51-Quartz support, 52-Substrate carrier.

[0048] 411-First driving gas jet hole, 412-First driving gas equalization chamber, 413-First driving gas inlet hole, 414-First driving gas inlet pipe, 415-First driving gas flow controller.

[0049] 431 - Second driving gas jet port, 432 - Second driving gas equalization chamber, 433 - Second driving gas inlet port, 434 - Second driving gas inlet pipe, 435 - Second driving gas flow controller.

[0050] 4201-Suspended gas inlet, 4202-Suspended gas equalization chamber, 4203-Suspended gas outlet, 4204-Suspended gas chamber, 4205-Suspended gas exhaust channel, 4206-Suspended gas exhaust port, 4207-Suspended gas exhaust chamber, 4208-Suspended gas exhaust port; 4209-Suspended gas exhaust pipe, 4210-Suspended gas vacuum pump, 4211-Suspended gas inlet pipe, 4212-Suspended gas flow controller, 4213-Electromagnetic coil element.

[0051] 441 - Conical surface on the base of the rotating component; 442 - Groove on the outer side of the base of the rotating component; 443 - Groove on the inner side of the base of the rotating component; 444 - Array of permanent magnets.

[0052] 511 - Upper conical surface of quartz support; 512 - Lower conical surface of quartz support.

[0053] 521 - Rounded corner structure on the edge of the substrate disk; 522 - Rounded corner structure on the lower edge of the substrate disk; 523 - Lower conical surface of the substrate disk; 524 - Side conical surface of the substrate disk. Detailed Implementation

[0054] The present invention will now be described in detail with reference to the accompanying drawings and preferred embodiments, so that those skilled in the art can understand and implement the present invention without creative effort. Example 1

[0055] This embodiment provides an MOCVD reaction chamber, such as... Figure 1 As shown, it includes a spray head 1, a vacuum chamber shell 2, an exhaust gas collection and discharge device 3, a rotating assembly 4, a substrate support assembly 5, and a heating assembly 6.

[0056] The vacuum chamber shell 2 consists of an upper vacuum chamber sidewall 21, a lower vacuum chamber sidewall 22, a lower vacuum chamber outer bottom plate 23, a lower vacuum chamber inner bottom plate 25, and a vacuum chamber bottom plate 24. The vacuum chamber shell 2 is connected to the spray head 1 above it, forming a sealed vacuum reaction environment. The exhaust gas collection and discharge device 3 is integrated into the vacuum chamber shell 2 in a ring structure.

[0057] The rotating assembly 4 consists of a first radial jet device 41, a second radial jet device 43, a gas-magnetic combined support device 42, and a rotating assembly base 44. The substrate carrier assembly 5 includes a substrate carrier disk 52 and a quartz support 51 located below the spray head 1 for carrying the wafer. The quartz support 51 and the rotating assembly base 44 are connected by mutually mating conical surfaces. The heating assembly 6 is disposed within a heating chamber enclosed by the substrate carrier disk 52, the quartz support 51, the rotating assembly base 44, and the vacuum chamber base plate 24.

[0058] Specifically, such as Figure 1 , 2 As shown, the first radial jet device 41 is integrated between the lower cavity sidewall 22 of the vacuum chamber and the lower cavity outer bottom plate 23 of the vacuum chamber, and the second radial jet device 43 is integrated between the lower cavity outer bottom plate 23 of the vacuum chamber and the vacuum chamber bottom plate 24. The first radial jet device 41 and the second radial jet device 43 are coaxially mounted. The first radial jet device 41 is sleeved on the outer periphery of the rotating component base 44, and the second radial jet device 43 is embedded in the inner periphery of the rotating component base 44. The gas-magnetic combined support device 42 is integrated on the lower cavity outer bottom plate 23 of the vacuum chamber. The first radial jet device 41, the second radial jet device 43, and the gas-magnetic combined support device 42 form a groove. The rotating component base 4 is accommodated in this groove and is located above the gas-magnetic combined support device 42. The first radial jet device 41 and the second radial jet device 43 are used to drive the rotating component base 44 to rotate, and the gas-magnetic combined support device 42 is used to support and drive the rotating component base 44 to levitate. The rotating component base 44 serves as the power receiving and levitation body.

[0059] Specifically, such as Figure 3 , 4As shown, the first radial jet device 41 has an annular structure, including interconnected first driving gas jet holes 411, a first driving gas equalization chamber 412, a first driving gas inlet 413, a first driving gas inlet pipe 414, and a first driving gas flow controller 415. The first driving gas jet holes 411 are located on the inner surface of the first radial jet device 41 and are evenly distributed around the circumference. The first driving gas inlet holes 413 are located on the outer surface of the first radial jet device 41 and are also evenly distributed around the circumference. The first driving gas jet holes 411 and the first driving gas inlet holes 413 are connected through the first driving gas equalization chamber 412. The first driving gas inlet pipe 414 and the first driving gas flow controller 415 are located outside the first radial jet device 41, and the first driving gas flow controller 415 is connected to the first driving gas inlet holes 413 through the first driving gas inlet pipe 414. The first driving gas jet hole 411 and the inner surface of the first radial jet device 41 have a first deflection angle θ1 in the normal direction. The deflection direction of the first deflection angle θ1 is the same as the preset rotation direction of the rotating component base 44, 30°≤θ1≤45°.

[0060] Specifically, such as Figure 5 , 6 As shown, the second radial jet device 43 is also an annular structure, including a second driving gas jet port 431, a second driving gas equalization chamber 432, a second driving gas inlet port 433, a second driving gas inlet pipe 434, and a second driving gas flow controller 435. The second driving gas jet port 431 is located on the outer surface of the second radial jet device 43 and is evenly distributed around the entire circumference. The second driving gas inlet port 433 is located on the inner surface of the second radial jet device 43 and is also evenly distributed around the entire circumference. The second driving gas jet port 431 and the second driving gas inlet port 433 are connected through the second driving gas equalization chamber 432. The second driving gas inlet pipe 434 and the second driving gas flow controller 435 are located outside the second radial jet device 43, and the second driving gas flow controller 435 is connected to the second driving gas inlet port 433 through the second driving gas inlet pipe 434. There is a second deflection angle θ2 between the central axis of the second driving gas jet hole 431 and the normal direction of the outer surface of the second radial jet device 43. The deflection direction of the second deflection angle θ2 is the same as the preset rotation direction of the rotating component base 44, 30°≤θ2≤45°.

[0061] In this embodiment, the first driving gas jet orifice 411 and the second driving gas jet orifice 431 are divided into four (or more) groups. Each group of first driving gas jet orifices 411 and second driving gas jet orifices 431 is connected to an independent airflow channel, which can be controlled individually. A position sensor can detect the air gap width between the rotating component base 51 and the radial jetting devices (31 and 32) in real time, and based on this feedback signal, the airflow rate of each group of jet orifices can be independently adjusted. This actively controls the radial position of the rotating component base 44, optionally allowing the base to remain coaxial with or offset from the vacuum chamber housing to meet unique epitaxial process requirements.

[0062] Specifically, such as Figure 8 , 9 As shown, the gas-magnetic combined support device 42 includes a suspended gas inlet 4201, a suspended gas equalization chamber 4202, a suspended gas outlet 4203, a suspended gas chamber 4204, a suspended gas exhaust channel 4205, a suspended gas exhaust port 4206, a suspended gas exhaust chamber 4207, a suspended gas exhaust port 4208, and an electromagnetic coil element 4213. The suspended gas inlet 4201 and the suspended gas exhaust port 4208 are located on the lower end face of the gas-magnetic combined support device 42, with the suspended gas inlet 4201 evenly distributed around the circumference. The suspended gas outlet 4203, the suspended gas chamber 4204, the suspended gas exhaust channel 4205, and the suspended gas exhaust port 4206 are located on the upper end face of the gas-magnetic combined support device 42, and are evenly distributed around the circumference. The suspended gas equalization chamber 4202 and the suspended gas exhaust chamber 4207 are located inside the gas-magnetic combined support device 42. Suspended gas inlet 4201 and suspended gas outlet 4203 are connected through suspended gas equalization chamber 4202. Suspended gas exhaust outlet 4206 and suspended gas exhaust outlet 4208 are connected through suspended gas exhaust chamber 4207. Suspended gas exhaust pipe 4209, suspended gas vacuum pump 4210, suspended gas inlet pipe 4211, and suspended gas flow controller 4212 are located outside the gas-magnetic combined support device 42. The gas-magnetic combined support device 42 is connected to the external suspended gas exhaust pipe 4209 and suspended gas vacuum pump 4210 through suspended gas exhaust outlet 4208. The gas-magnetic combined support device 42 is connected to the external suspended gas inlet pipe 4211 and suspended gas flow controller 4212 through suspended gas inlet 4201. Electromagnetic coil element 4213 is located inside the gas-magnetic combined support device near the upper end face.

[0063] Specifically, such as Figure 1 , 7As shown in Figure 10, the rotating component base 44 is made of high-purity isostatic graphite and coated with a chemical vapor deposition (CVD) silicon carbide coating to resist corrosion from reactant gases. During MOCVD equipment operation, the radially outer side of the rotating component base 44 maintains a first driving air gap with the inner side of the first radial jet device 41, and the radially inner side of the rotating component base 44 maintains a second driving air gap with the outer side of the second radial jet device 43. The widths of both the first and second driving air gaps are controlled within the range of 20 to 100 micrometers. An air-floating gap is formed between the lower surface of the rotating component base 44 and the upper surface of the gas-magnetic combined support device 42, and the width of the air-floating gap ranges from 10 to 20 micrometers.

[0064] like Figure 11 As shown, the upper surface of the rotating component base 44 is a conical surface, namely the upper conical surface 441 of the rotating component base. Several grooves are uniformly arranged along the circumferential direction on the radially outer and radially inner surfaces of the rotating component base 44, namely the outer groove 442 and the inner groove 443 of the rotating component base. In this embodiment, the outer groove 442 and the inner groove 443 of the rotating component base are arranged vertically. A permanent magnet array 444 is embedded in the bottom of the rotating component base 44; the permanent magnet array 444 is a Heilbeck array.

[0065] In addition, such as Figure 12 As shown, the arrangement of the outer groove 442 and the inner groove 443 of the rotating component base can also be inclined. Their inclination direction is coordinated with the injection direction of the corresponding driving gas throttling orifice. For example, if the driving direction is counterclockwise, the grooves are also inclined counterclockwise. When the driving airflow impacts the inclined surface, it generates an upward axial force, which can offset part of the weight of the rotating component, directly reducing the load on the gas-magnetic combined support device 42.

[0066] like Figure 13 As shown, the arrangement of the outer groove 442 and the inner groove 443 of the rotating component base can also be fishbone shaped. They are separated axially by an annular protrusion, forming upper and lower regions. When the driving airflow impacts this structure, the inclined protrusion guides the airflow towards the center, forming a local high-pressure zone. This high-pressure zone provides additional air film stiffness, acting like a "pneumatic positioning clamp," significantly suppressing radial runout during rotation and improving dynamic stability.

[0067] Specifically, such as Figure 1 and 14As shown, the exhaust gas collection and discharge device 3 is located 5mm-10mm below the edge of the substrate carrier disk 5. The inner wall of the exhaust gas collection and discharge device 5 is provided with an annular groove 36 and circumferentially distributed inlet holes 31 and outlet holes 33. The top of the annular groove 36 has a rounded corner transition. Both the inlet holes 31 and the outlet holes 33 are connected to the exhaust gas collection chamber 32. The inlet holes 31 are located inside the vacuum chamber shell 2, and the outlet holes 33 are located outside the vacuum chamber shell 2. The sum of the cross-sectional areas of the inlet holes 31 is equal to 0.9 times the sum of the cross-sectional areas of the outlet holes 33. The exhaust gas collection and discharge device 3 also includes a suction pipe 34 and a vacuum pump 35 for exhausting the exhaust gas.

[0068] Specifically, such as Figure 1 , 15 As shown in Figure -17, both the upper and lower surfaces of the quartz support 51 are conical surfaces, namely the upper conical surface 511 and the lower conical surface 512. The lower surface of the edge of the substrate carrier 52 is also a conical surface, namely the lower conical surface 523. During installation, the upper conical surface 441 of the rotating component base and the lower conical surface 512 of the quartz support mate to connect the rotating component base 44 and the quartz support 51. The upper conical surface 511 of the quartz support and the lower conical surface 523 of the substrate carrier mate to connect the quartz support 51 and the substrate carrier 52. This multi-stage conical surface mating structure ensures precise alignment and synchronous rotation of the three components at high temperatures and effectively compensates for dimensional changes caused by the difference in thermal expansion coefficients between graphite and quartz, maintaining the stability of the rotation axis. Simultaneously, this structure facilitates disassembly and maintenance.

[0069] Specifically, such as Figure 18 As shown, the side structure of the substrate carrier disk 52 is a tapered surface 524, which is smaller at the top and larger at the bottom. The tapered surface 524 and the upper surface of the substrate carrier disk are transitioned by a rounded corner structure 521 at the edge of the substrate carrier disk, which is an outwardly convex rounded corner. The tapered surface 524 and the lower surface of the substrate carrier disk are transitioned by a rounded corner structure 522 at the bottom edge of the substrate carrier disk, which is an inwardly concave rounded corner. The side of the substrate carrier disk 52 has a streamlined structure. The tapered surface 524 and the inner wall of the vacuum chamber shell 2 together form a tapered channel. The above-mentioned streamlined structure and tapered channel can effectively guide the downward airflow from the spray head 1 and the upward airflow from the rotating component 4, so that they smoothly converge at the edge of the carrier disk, stably transition to laminar flow to avoid the generation of eddies, and finally flow stably to the exhaust gas collection and discharge device 3, reducing the interference of the upward airflow on the vacuum chamber.

[0070] Specifically, the heating assembly 6 includes a graphite heater, a heater support, and electrodes. The heater is coaxial and parallel to the substrate carrier 52. Since the entire air flotation and drive system is integrated into the cavity sidewall and bottom, and the substrate carrier 52 itself is a complete, non-perforated structure, this ensures that the radiant heat field generated by the heater acts uniformly and without interference on the substrate carrier, which is crucial for achieving wafer temperature uniformity. Simultaneously, the drive and support devices are spatially decoupled from the heating assembly, avoiding mutual interference. This allows the heater support to be designed with more mechanical support points, effectively suppressing thermal creep deformation under high-temperature operating conditions. Example 2

[0071] This embodiment provides a control method for the MOCVD reaction chamber in Embodiment 1, including: (1) Hover Start First, the levitation gas vacuum pump 4210, connected to the gas-magnetic combined support device 42, is started to pre-establish a negative pressure environment in the internal pipelines of the gas-magnetic combined support device 42. Then, the electromagnetic coil element 4213 inside the gas-magnetic combined support device 42 is started, generating a repulsive electromagnetic force between the electromagnetic coil element 4213 and the permanent magnet array 444 at the lower end of the rotating component base 44. This electromagnetic force counteracts most of the gravity of the substrate-supporting component 5 and the rotating component base 44. Subsequently, high-purity nitrogen (or argon) is introduced into the system as a flotation medium through the levitation gas flow controller 4212. The levitation gas pressure is precisely controlled between 0.3 and 0.8 MPa (approximately 3 to 8 atmospheres) by the flow controller.

[0072] High-pressure suspended gas flows sequentially through the suspended gas inlet pipe 4211 located outside the vacuum chamber, through the suspended gas inlet hole 4201 passing through the vacuum chamber wall, and enters the annular suspended gas uniform chamber 4202 inside the gas-magnetic combined support device 42. The suspended gas uniform chamber 4202 effectively buffers pressure fluctuations and ensures uniform circumferential pressure distribution. Subsequently, the suspended gas is ejected through dozens of small-diameter suspended gas outlet holes 4203 evenly distributed on the circumference, first forming a tiny air-floating gap between the upper end face of the gas-magnetic combined support device 42 and the lower end face of the rotating component base 44, and then the suspended gas is continuously injected into the tiny air-floating gap by throttling.

[0073] Based on the orifice throttling effect, a highly rigid gas film is formed in the air flotation gap. The load-bearing capacity of this gas film, combined with the repulsive force between the electromagnetic coil element 4213 and the permanent magnet array 444, is sufficient to overcome the weight of the entire substrate support assembly 5 (substrate carrier 52, quartz support 51) and the rotating assembly base 44, allowing the rotating assembly base 44 and the substrate support assembly 5 to be stably suspended. The rotating assembly base 44 and the air-magnetic combined support device 42 below achieve contactless support. The used air flotation gas diffuses in all directions, enters the suspended gas exhaust channel 4205, and enters the suspended gas exhaust uniform chamber 4207 through the suspended gas exhaust port 4206. Finally, it is discharged from the system through the suspended gas exhaust pipe 4209 and the suspended gas vacuum pump 4210, thereby maintaining the dynamic balance of the airflow.

[0074] (2) Rotary drive: After confirming that the rotating component is stably suspended, the radial jet device is activated.

[0075] Drive gas (high-purity nitrogen) with a pressure of 0.2 to 0.6 MPa is introduced into the first radial jet device 41 and the second radial jet device 43 through the first drive gas flow controller 415 and the second drive gas flow controller 435, respectively.

[0076] The first radial jet device 41 is activated (see...) Figure 4 The driving gas enters the annular first driving gas homogenizing chamber 412 through the first driving gas inlet pipe 414 and the first driving gas inlet hole 413. The homogenized driving gas is then ejected obliquely from dozens of circumferentially equidistant first driving gas jet holes 411.

[0077] The second radial jet device 43 is activated (see...) Figure 5 The driving gas enters the annular second driving gas homogenizing chamber 432 through the second driving gas inlet pipe 434 and the second driving gas inlet hole 433. The homogenized driving gas is then ejected obliquely from dozens of circumferentially equidistant second driving gas jet holes 431.

[0078] These tilted, high-speed driven airflows impact the outer surface of the rotating component base 44. For example... Figure 9 As shown, multiple circumferentially equidistant vertical grooves 442 are formed on the outer surface of the rotating component base 44. When the driving airflow impacts the grooves, the generated force can be decomposed into radial force and tangential force. The radial forces generated by all the jet holes cancel each other out due to their symmetrical distribution, and their resultant force is zero; while all the tangential forces are superimposed and synthesized into a pure torque that drives the rotating component base 44 to rotate in a specific direction.

[0079] By independently controlling the flow rate or pressure of the driving gas of the first radial jet device 41 and the second radial jet device 43, the driving torque can be precisely adjusted, thereby enabling the rotating component base 44 to operate stably within the range of 0 to 1000 rpm.

[0080] Furthermore, the deflection direction of the second deflection angle θ2 of the second driving gas jet port 431 in the second radial jet device 43 can be opposite to the preset rotation direction of the rotating component base 44, so that the driving torque generated by the first radial jet device 41 and the second radial jet device 43 is also opposite. By adjusting the flow rate difference between the first radial jet device 41 and the second radial jet device 43, precise control of the rotational speed of the rotating component base 44 can be achieved, and even rapid braking can be realized.

[0081] In addition, by independently controlling the magnitude and direction of the electromagnetic force of each pole of the electromagnetic coil near the upper end face of the gas-magnetic combined support device 42, as well as the gas flow rate of the upper and lower jet holes of the first radial jet device 41 and the second radial jet device 43, the spatial position and attitude of the rotating component base 44 in the axial and tilt directions can be finely controlled to ensure that the rotating component base 44 and the vacuum chamber shell 2 always maintain good perpendicularity.

[0082] (3) Heating and thin film deposition: After the rotating assembly base 44 reaches the predetermined rotation speed, the heating assembly 6 is activated. Current is introduced into the heater through electrodes passing through the vacuum chamber base plate 24, causing it to heat up. The heater uniformly heats the rotating substrate carrier 52 above through thermal radiation, enabling the wafer on the substrate carrier 52 to reach and maintain a deposition temperature of 1000°C to 1200°C. Thanks to the complete substrate carrier structure and stable rotation, the radial and circumferential temperature uniformity of the wafer can be controlled within ±1°C.

[0083] At this point, the metal-organic source and reactant gases, such as hydrides, are uniformly injected into the reaction chamber through spray head 1. For example... Figure 18 As shown, the downward main airflow from the spray head 1 and the small amount of driving exhaust gas escaping from around the quartz support 51 smoothly converge under the guidance of the unique streamlined structure at the edge of the substrate carrier 52 (rounded corner structure 521 on the upper edge of the substrate carrier 52, rounded corner structure 522 on the lower edge of the substrate carrier 52, and tapered surface 524 on the side of the substrate carrier 52), and stably transition into laminar flow. Finally, it is uniformly discharged from the reaction chamber by the exhaust gas collection and discharge device 3. This design effectively avoids the generation of eddies and ensures the stability and uniformity of the reactive gas at the boundary layer on the wafer surface, thereby achieving high-quality, high-uniformity thin film epitaxial growth.

[0084] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the technical solutions and core ideas of this application. Therefore, any changes or modifications made by those skilled in the art based on the ideas of this application, and on the specific implementation methods and application scope of this application, are all within the scope of protection of this application. In summary, the content of this specification should not be construed as a limitation of this application.

Claims

1. An MOCVD reaction chamber, comprising a vacuum chamber shell, a spray head, a substrate support assembly, a heating assembly, a rotating assembly, and a tail gas collection and exhaust device, characterized in that: The rotating component includes a rotating component base, which is levitated and supported by a combination of gas and magnetism and is driven to rotate by gas injection; the rotating component base and the substrate support component are connected by mutually cooperating conical surfaces, which drive the substrate support component to rotate synchronously. The substrate support assembly includes a substrate carrier disk for supporting the substrate, and the edges of the substrate carrier disk have a streamlined structure; The exhaust gas collection and discharge device is integrated into the vacuum chamber housing in a ring structure and is located between the substrate carrier disk and the rotating assembly.

2. The MOCVD reaction chamber according to claim 1, characterized in that: The rotating assembly further includes a radial jetting device and a gas-magnetic combined support device integrated on the vacuum chamber housing, the radial jetting device and the gas-magnetic combined support device forming a groove; the rotating assembly base is housed in the groove and located above the gas-magnetic combined support device; the radial jetting device and the gas-magnetic combined support device are provided with a gas equalization chamber and a plurality of jet holes communicating with the gas equalization chamber on their inner surfaces facing the rotating assembly base; magnetic elements are respectively provided on the top of the gas-magnetic combined support device and the bottom of the rotating assembly base.

3. The MOCVD reaction chamber according to claim 2, characterized in that: The base of the rotating component has a plurality of grooves uniformly arranged along the circumferential direction on its radially outer and / or radially inner sides; the grooves are arranged in one of the following ways: vertical, inclined or herringbone.

4. The reaction chamber of the MOCVD equipment according to claim 2, characterized in that, The radial jet device includes a first radial jet device and a second radial jet device arranged coaxially. The first radial jet device is sleeved on the outer periphery of the rotating component base, and the second radial jet device is embedded in the inner periphery of the rotating component base. There is an air gap between the first radial jet device and the second radial jet device and the rotating component base.

5. The MOCVD reaction chamber according to claim 4, characterized in that, Both the first and second radial jet devices include: a gas flow controller, an air inlet pipe, a gas equalization chamber, and multiple jet holes equidistantly distributed on the circumference; the central axis of each jet hole is located in a plane parallel to the upper end face of the rotating component base, and is perpendicular to but does not intersect with the central axis of the rotating component base; the central axis of the jet hole of the first radial jet device has a first deflection angle θ1 with the normal direction of the inner surface of the first radial jet device, and the deflection direction of the first deflection angle θ1 is the same as or opposite to the preset rotation direction of the rotating component base, 30°≤θ1≤45°; the central axis of the jet hole of the second radial jet device has a second deflection angle θ2 with the normal direction of the outer surface of the second radial jet device, and the deflection direction of the second deflection angle θ2 is the same as or opposite to the preset rotation direction of the rotating component base, 30°≤θ2≤45°.

6. The MOCVD reaction chamber according to claim 5, characterized in that: The jet orifices are divided into multiple groups, and the jet orifices in each group are connected to an independent airflow channel, which can be controlled individually.

7. The MOCVD reaction chamber according to claim 2, characterized in that: The upper end face of the gas-magnetic combined support device is provided with air outlet small holes which are circumferentially and uniformly distributed, and the air outlet small holes are communicated through a gas uniforming cavity inside the gas-magnetic combined support device; when the air outlet small holes discharge air, a gas film is formed between the upper end face of the gas-magnetic combined support device and the lower end face of the rotating component base.

8. The MOCVD reaction chamber according to claim 2, characterized in that: A permanent magnet array is embedded at the bottom of the rotating component base; at least an electromagnetic coil element divided into at least 3 poles is embedded in the upper part of the gas-magnetic combined support device.

9. The MOCVD reaction chamber according to claim 8, characterized in that: The permanent magnet array is a Halbach array.

10. The MOCVD reaction chamber according to claim 1, characterized in that, The tail gas collection and discharge device is located 5 mm - 10 mm below the edge of the substrate carrier; an annular groove, intake through holes and outlet through holes distributed circumferentially are provided on the inner wall of the tail gas collection and discharge device, the top of the annular groove is in fillet transition, and both the intake through holes and the outlet through holes are connected to the tail gas collection cavity; the intake through holes are located inside the vacuum chamber housing, and the outlet through holes are located outside the vacuum chamber housing; the sum of the cross-sectional areas of the intake through holes is equal to 0.9 - 1 times the sum of the cross-sectional areas of the outlet through holes.

11. The MOCVD reaction chamber according to claim 1, characterized in that, The substrate bearing component further includes a quartz support member located below the substrate carrier; upper concave conical surfaces with the small end upwards and the large end downwards are provided on the lower end face of the substrate carrier and the upper end face of the quartz support member, and they are connected in cooperation through the upper concave conical surfaces; the thermal expansion coefficient of the substrate carrier is greater than that of the quartz support member, and in the horizontal direction, the quartz support member is located inside the substrate carrier.

12. The MOCVD reaction chamber according to claim 11, characterized in that, Upper concave conical surfaces with the small end upwards and the large end downwards are provided on the lower end face of the quartz support member and the upper end face of the rotating component base, and they are connected in cooperation through the upper concave conical surfaces; the thermal expansion coefficient of the rotating component base is greater than that of the quartz support member, and in the horizontal direction, the quartz support member is located inside the rotating component base.

13. The MOCVD reaction chamber according to claim 1, characterized in that, The side surface of the substrate carrier is a conical surface with the upper part smaller and the lower part larger, and the conical surface is in convex fillet transition with the upper surface of the substrate carrier and in concave fillet transition with the lower surface, forming a streamline structure; the conical surface and the inner wall of the vacuum chamber housing together form a tapered pipe, and the distance between the upper end of the conical surface and the inner wall of the vacuum chamber housing is 2 times the distance between the lower end of the conical surface and the inner wall of the vacuum chamber housing.

14. The MOCVD reaction chamber according to claim 1, characterized in that, The cross-section combination of the rotating component and the substrate bearing component forms a "冂”-shaped structure, and the central internal area enclosed by the "冂”-shaped structure is a non-rotating area.

15. A method for controlling an MOCVD reaction chamber according to any one of claims 1-14, characterized in that, Including: Start the rotating component to make the rotating component base levitate under the combined action of gas and magnetism; Inject driving gas to make the rotating component base rotate and带动 the substrate bearing component to rotate synchronously; Start the heating component to heat the substrate carrier until it reaches the preset temperature; Inject MO source from the spray head into the reaction chamber for epitaxial growth; The tail gas of the epitaxial growth and the tail gas of the driving gas are smoothly converged under the guidance of the streamline structure at the edge of the substrate carrier, and are stably transitioned into laminar flow and discharged from the reaction chamber by the tail gas collection and discharge device.

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