Production equipment for high-resistance epitaxial wafer with heavily phosphorus-doped substrate

Abstract

The invention discloses heavily phosphorus-doped substrate high-resistance epitaxial wafer production equipment, and particularly relates to the technical field of epitaxial equipment.The equipment comprises an equipment body, a gas mixing part and a placement part, the equipment body comprises a shell, a heating mechanism and a lifting platform are arranged in the shell, and the gas mixing part comprises a four-way pipe; a mixing barrel is arranged at one end of the four-way pipe, a stirring mechanism is arranged at the free end of the mixing barrel, an air outlet pipe is arranged on the lower portion of the stirring mechanism, a plurality of spray heads are arranged on the air outlet pipe, the placing part comprises a rotating shaft, the rotating shaft is driven by a driving mechanism, a base is arranged on the rotating shaft, and a plurality of trays are arranged on the side face of the base. Through the gas mixing structure, the uniform gas distribution design, the flexible operation mode and the stable and durable structural material, the problem of non-uniform gas mixing in the epitaxial growth process is effectively solved, and the uniformity and production efficiency of epitaxial growth are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of epitaxial equipment, and more specifically, to a production device for high-resistance epitaxial wafers with heavily phosphorus-doped substrates. Background Art

[0002] Epitaxial wafer production equipment is a key equipment for the preparation of semiconductor materials. It forms a single crystal film consistent with the substrate lattice structure by directionally crystallizing gaseous substances on a single crystal substrate under a high temperature environment. With the development of power electronics technology towards high frequency, energy saving, lightweight and miniaturization, new requirements are put forward for the frequency characteristics, switching characteristics, power capacity, power loss, high reliability and low cost of power semiconductor devices. Integrated circuit switching power supply Schottky diodes and field-controlled high-frequency power electronic devices made of silicon epitaxial wafers on heavily phosphorus-doped substrates are the preferred products. Choosing a phosphorus-doped low-resistivity substrate is mainly to significantly reduce the proportion of voltage drop caused by the semiconductor part in the voltage drop and the on-resistance. Another important influencing factor is the current distribution, which is kept as balanced as possible throughout the chip range and minimizes the extended resistance of the metallization at the front end of the chip, thereby minimizing the saturation resistance and improving device performance.

[0003] The Chinese patent application number 202210428945.8 discloses an epitaxial growth device, including a furnace body, a reaction chamber, a first reaction base and a second reaction base arranged horizontally, respectively, in the reaction chamber, and the first reaction base and the second reaction base are arranged at intervals along the horizontal direction. The furnace body is also provided with a first air inlet, a second air inlet and an air outlet respectively connected to the reaction chamber, the first reaction base is arranged between the first air inlet and the air outlet, and the second reaction base is arranged between the second air inlet and the air outlet; the reaction medium can enter the reaction chamber through the first air inlet and the second air inlet, respectively, and leave the reaction chamber through the air outlet.

[0004] Although the epitaxial growth device provided by the patent solves the problem of low epitaxial layer output efficiency of existing epitaxial furnaces, the device lacks a gas mixing structure and cannot mix the epitaxial gas and the doping gas. Directly introducing the gas into the reaction vessel for epitaxial reaction will cause uneven mixing of the gas in the reaction vessel, resulting in excessively fast or too slow growth rates in local areas, causing fluctuations in epitaxial layer thickness. When the doping gas is not fully mixed, the epitaxial layer doping distribution will be gradient or island-shaped, directly affecting the resistivity distribution of the device.

[0005] Therefore, the present invention proposes a device for producing high-resistance epitaxial wafers with heavily phosphorus-doped substrates to solve the above problems. Summary of the invention

[0006] In order to overcome the above defects of the prior art, an embodiment of the present invention provides a device for producing high-resistance epitaxial wafers with heavily phosphorus-doped substrates, which solves the problems raised in the above background technology by providing a gas mixing unit and a placement unit.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solutions: a device for producing high-resistance epitaxial wafers on heavily phosphorus-doped substrates, comprising a device body, the device body comprising a shell, a heating mechanism is provided in the upper part of the shell, the heating mechanism is used to provide a high-temperature reaction space, a lifting platform is provided in the shell below the heating mechanism, the lifting platform is used to take and place wafers; A gas mixing part, the gas mixing part comprises a four-way pipe, one end of the four-way pipe is provided with a mixing cylinder, the free end of the mixing cylinder is provided with a stirring mechanism, the lower part of the stirring mechanism is provided with two symmetrically distributed gas outlet pipes, the gas outlet pipes are provided with a plurality of nozzles, and the nozzles are provided with a plurality of gas injection holes; A placement part, the placement part includes a rotating shaft rotatably connected to the lifting platform, the rotating shaft is driven by a driving mechanism, a base located above the lifting platform is provided on the rotating shaft, a plurality of trays are provided on the side of the base, the trays are used to place wafers, and each of the trays can be aligned with the nozzle on the corresponding side; When the driving mechanism drives the rotating shaft to rotate, the stirring mechanism can rotate along with the rotating shaft.

[0008] Preferably, the heating mechanism comprises a heating cavity with an opening facing downward, the heating cavity is made of quartz material to achieve a better heat preservation effect, and a heating coil is provided between the heating cavity and the outer shell.

[0009] Preferably, the lifting platform includes a lifting plate, which is made of quartz material. The lifting plate can cover the opening at the bottom of the heating cavity to achieve a better insulation effect. A plurality of electric telescopic rods distributed in a rectangular array are provided at the bottom of the lifting plate, and the electric telescopic rods are used to drive the lifting plate to move up and down.

[0010] Preferably, a spiral plate is provided in the mixing drum, and the stirring mechanism includes a stirring barrel connected to the mixing barrel, and a stirring shaft is rotatably connected in the stirring barrel. A plurality of stirring rods evenly distributed along the circumferential direction are provided on the upper and lower sides of the stirring shaft, and the stirring rods on the upper and lower sides are staggered, and each of the stirring rods is provided with a plurality of vertical rods perpendicular to it.

[0011] Preferably, the driving mechanism comprises a supporting plate fixed to the lifting plate, a motor is provided on the supporting plate, and an output end of the motor is fixed to the rotating shaft.

[0012] Preferably, the base is provided with a plurality of self-rotation mechanisms corresponding one-to-one with the trays, the self-rotation mechanisms include a short shaft rotatably connected to the base, one end of the short shaft is fixed to the tray on the corresponding side, and the other end is provided with a turntable, the side surface of the turntable is provided with a plurality of blades evenly distributed along the circumferential direction, and the base is provided with a plurality of through grooves located around the short shaft, and each of the through grooves corresponds to a plurality of blades on the corresponding side.

[0013] Preferably, a sleeve is provided at the top of the rotating shaft and is located below the stirring shaft. A plurality of slots evenly distributed along the circumferential direction are provided on the inner surface of the sleeve. The slots gradually widen toward the stirring shaft. A plurality of plug-in blocks that can be inserted into the slots are provided at the lower part of the stirring shaft.

[0014] Preferably, the base is in the shape of a polygonal cone with a small top and a large bottom to achieve a better epitaxial effect, and a plurality of through holes are provided at the bottom of the base.

[0015] Preferably, two symmetrically distributed material holes are provided at the lower part of the shell to facilitate the taking and placing of wafers.

[0016] Preferably, a first joint, a second joint and a third joint are provided on the top of the shell, and the first joint, the second joint and the third joint are respectively connected to the other three ends of the four-way pipe.

[0017] Technical effects and advantages of the present invention: 1. The present invention is provided with a gas mixing section, wherein the four-way pipe can make the epitaxial gas and the doping gas collide and mix for the first time, and the spiral guide effect of the spiral plate in the mixing barrel can mix for the second time, and then pass into the stirring mechanism. The stirring shaft and stirring rod design in the stirring mechanism can mix the epitaxial gas and the doping gas for the third time, and the two gases are evenly distributed in the mixed gas through multiple mixing, further enhancing the gas mixing effect. In addition, this design ensures that the gas is fully mixed before entering the reaction vessel, and finally reaches the reaction space through the uniformly distributed jet holes on the nozzle, avoiding the problem of too fast or too slow growth rate in the local area, thereby reducing the fluctuation of the thickness of the epitaxial layer.

[0018] 2. The present invention realizes uniform heating and gas contact of the epitaxial wafers on the tray during the reaction process through the design of the placement part. The tray can accurately align the nozzle to ensure that the gas is evenly distributed on each epitaxial wafer, and multiple trays are arranged on the base, which can enable multiple wafers to undergo epitaxial growth at the same time, thereby accelerating the efficiency of epitaxial growth. In addition, the design of the rotation mechanism enables the tray to rotate, further promoting the uniform distribution of gas on the surface of the epitaxial wafer and improving the uniformity of epitaxial growth.

[0019] 3. The present invention takes into account the flexibility and automation of operation. The lifting platform is moved up and down by an electric telescopic rod, which is convenient for placing and removing epitaxial wafers. In addition, a sleeve is arranged between the rotating shaft and the stirring shaft, so that the stirring shaft can rotate with the rotation of the rotating shaft. The driving mechanism drives the rotation of the rotating shaft and the stirring mechanism through an electric motor, making full use of the power of the driving mechanism to achieve gas mixing and uniform heating of the epitaxial wafers. This design reduces manual operation and improves production efficiency.

[0020] 4. The structure and material selection of the present invention take into account the stability and durability in high temperature environments. The heating mechanism uses a heating cavity and heating coil made of quartz material, which can withstand high temperatures and maintain structural stability. The lifting platform is also made of quartz material to ensure durability in high temperature environments. In addition, the connection and sealing design between the various parts of the equipment also takes into account the sealing and safety of the gas, ensuring the stable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0022] Figure 2 It is a cutaway view of the overall structure of the present invention.

[0023] Figure 3 It is an exploded view of the four-way pipe and the mixing cylinder of the present invention.

[0024] Figure 4 It is a cross-sectional view of the four-way pipe and the mixing cylinder of the present invention.

[0025] Figure 5 It is a schematic diagram of the structure of the gas mixing unit of the present invention.

[0026] Figure 6 It is an exploded view of the gas mixing unit of the present invention.

[0027] Figure 7 It is a structural schematic diagram of the placement part of the present invention.

[0028] Figure 8 It is a bottom view of the placement portion of the present invention.

[0029] Fig. 9 It is a structural schematic diagram of the base of the present invention.

[0030] Fig.10 It is an exploded view of the rotation mechanism of the present invention.

[0031] Fig.11 It is a top view of the sleeve of the present invention.

[0032] Fig.12 It is a cutaway view of the sleeve of the present invention.

[0033] The accompanying drawings are marked as follows: 1. Equipment body; 101. Shell; 102. Heating mechanism; 1021. Heating cavity; 1022. Heating coil; 103. Lifting platform; 1031. Lifting plate; 1032. Electric telescopic rod; 2. gas mixing part; 201. four-way pipe; 202. mixing cylinder; 203. stirring mechanism; 2031. stirring barrel; 2032. stirring shaft; 2033. stirring rod; 2034. vertical rod; 204. air outlet pipe; 205. nozzle; 206. air jet hole; 3. Placement part; 301. Rotating shaft; 302. Driving mechanism; 3021. Support plate; 3022. Motor; 303. Base; 304. Tray; 4. Spiral plate; 5. self-rotating mechanism; 501. short shaft; 502. rotating disk; 503. blades; 504. through slot; 6. Sleeve; 7. Slot; 8. Insert block; 9. Through hole; 10. Material hole; 11. First joint; 12. Second joint; 13. Third joint. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Embodiment 1 See also Figures 1 to 12 As shown, the equipment for producing high-resistance epitaxial wafers on heavily phosphorus-doped substrates according to the first embodiment of the present invention comprises an equipment body 1 , a gas mixing unit 2 and a placement unit 3 .

[0036] See also Figure 1 and Figure 2 As shown, the device body 1 includes a shell 101, a heating mechanism 102 is provided in the upper part of the shell 101, the heating mechanism 102 is used to provide a high-temperature reaction space, and a lifting platform 103 is provided in the shell 101 below the heating mechanism 102, and the lifting platform 103 is used to take and place wafers.

[0037] Combination Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, the gas mixing part 2 includes a four-way pipe 201, a mixing cylinder 202 is provided at one end of the four-way pipe 201, a stirring mechanism 203 is provided at the free end of the mixing cylinder 202, two symmetrically distributed air outlet pipes 204 are provided at the lower part of the stirring mechanism 203, a plurality of nozzles 205 are provided on the air outlet pipes 204, and a plurality of air injection holes 206 are opened on the nozzles 205.

[0038] Combination Figure 7 As shown, the placement portion 3 includes a rotating shaft 301 rotatably connected to the lifting platform 103, the rotating shaft 301 is driven by a driving mechanism 302, a base 303 located above the lifting platform 103 is provided on the rotating shaft 301, and a plurality of trays 304 are provided on the side of the base 303, the trays 304 are used to place wafers, and each tray 304 can be aligned with the nozzle 205 on the corresponding side.

[0039] When the driving mechanism 302 drives the rotating shaft 301 to rotate, the stirring mechanism 203 can rotate along with the rotating shaft 301 .

[0040] See also Figure 2 As shown, the heating mechanism 102 includes a heating cavity 1021 with an opening facing downward. The heating cavity 1021 is made of quartz material to achieve a better heat preservation effect. A heating coil 1022 is provided between the heating cavity 1021 and the housing 101 .

[0041] It should be noted that the heating coil 1022 is a prior art and can generate heat when powered on, and its specific structure will not be described in detail here.

[0042] See also Figure 2 As shown, the lifting platform 103 includes a lifting plate 1031, which is made of quartz. The lifting plate 1031 can cover the opening at the bottom of the heating chamber 1021 to achieve a better insulation effect. A plurality of electric telescopic rods 1032 distributed in a rectangular array are provided at the bottom of the lifting plate 1031. The electric telescopic rods 1032 are used to drive the lifting plate 1031 to move up and down.

[0043] It should be noted that the electric telescopic rod 1032 is a prior art and can be extended or shortened when powered on, and its specific structure will not be described in detail here.

[0044] Furthermore, technicians can connect the exhaust gas treatment equipment to the lifting plate 1031. When the lifting plate 1031 and the heating chamber 1021 form a closed space, the exhaust gas treatment equipment is connected to the closed space, which can absorb and treat the exhaust gas generated during the epitaxial process to prevent the exhaust gas from polluting the environment.

[0045] See also Figure 2As shown, the driving mechanism 302 includes a supporting plate 3021 fixed to the lifting plate 1031 , a motor 3022 is disposed on the supporting plate 3021 , and an output end of the motor 3022 is fixed to the rotating shaft 301 .

[0046] It should be noted that the motor 3022 is a prior art and can rotate when powered on, and its specific structure will not be described in detail here.

[0047] See also Figure 7 and Fig. 9 As shown, the base 303 is generally in the shape of a polygonal cone that is small at the top and large at the bottom to achieve a better epitaxial effect. A plurality of through holes 9 are provided at the bottom of the base 303. Two symmetrically distributed material holes 10 are provided at the lower part of the shell 101 to facilitate the placement and removal of wafers. A first joint 11, a second joint 12 and a third joint 13 are provided at the top of the shell 101. The first joint 11, the second joint 12 and the third joint 13 are respectively connected to the other three ends of the four-way pipe 201.

[0048] When in use, the technician needs to first connect the gas pipeline for pre-treatment of the wafer with the third joint 13, connect the epitaxial gas pipeline with the first joint 11, and connect the doping gas pipeline with the second joint 12. In the initial state, the lifting plate 1031 is in contact with the lower end of the heating chamber 1021, and the lifting plate 1031 covers the opening at the bottom of the heating chamber 1021.

[0049] It should be noted that the epitaxial gas is a mixture of two reactive gases, which can react chemically in a high-temperature environment to generate silicon, and the doping gas is also a mixture of two reactive gases, which can react chemically in a high-temperature environment to generate doping substances.

[0050] The staff controls the multiple electric telescopic rods 1032 to retract at the same time, and the multiple electric telescopic rods 1032 drive the lifting plate 1031 to move downward, and the lifting plate 1031 drives the placement part 3 to move downward, and the placement part 3 moves out of the heating chamber 1021 until the placement part 3 moves between the two material holes 10, so that the multiple electric telescopic rods 1032 stop retracting. At this time, the technicians can attach multiple wafers to multiple trays 304 in turn, and then control the multiple electric telescopic rods 1032 to extend, and the multiple electric telescopic rods 1032 jointly drive the lifting plate 1031 to rise.

[0051] When the lifting plate 1031 blocks the opening at the bottom of the heating chamber 1021, the technician controls the multiple electric telescopic rods 1032 to stop extending, energizes the heating coil 1022, and the heating coil 1022 starts to heat the heating chamber 1021. The technician can place a thermometer in the heating chamber 1021 and monitor the real-time temperature in the heating chamber 1021 through the thermometer, heat the temperature to the optimal temperature required for the gas reaction, and then start the motor 3022 to rotate. The output end of the motor 3022 drives the shaft 301 to rotate, and the shaft 301 drives the base 303 to rotate. The base 303 drives the multiple trays 304 and the wafers in the trays 304 to rotate around the shaft 301, and then open the valve of the gas pipeline for pre-treating the wafers, so that the pre-treatment gas enters the four-way pipe 201 through the third joint 13. Since the first joint 11 and the second joint 12 are both connected to the gas pipeline, and the valves of the two gas pipelines are in a closed state at this time, the pre-treatment gas can only flow out through the mixing barrel 202.

[0052] The pretreatment gas flows out through the gas outlet pipe 204, and then is ejected through the multiple jet holes 206 on the nozzle 205. The multiple jet holes 206 can spray the gas evenly onto the surface of the wafer, pretreat the surface of the wafer, and make the surface of the wafer more conducive to the epitaxial growth of the epitaxial layer. The multiple wafers are in a state of rotating around the rotating axis 301, and each wafer can be effectively pretreated.

[0053] After the pretreatment is completed, the technician closes the valve of the pretreatment gas pipeline, and then opens the valves of the epitaxial gas pipeline and the doping gas pipeline. In the prior art, flow meters are provided on the epitaxial gas pipeline and the doping gas pipeline. The staff can adjust the ratio of the two gases through the flow meters on the pipelines. The epitaxial gas enters the four-way pipe 201 through the first joint 11, and the doping gas enters the four-way pipe 201 through the second joint 12.

[0054] The fast-flowing epitaxial gas and doping gas collide and mix together in the four-way pipe 201, so that the two gases are mixed first and then introduced into the heating chamber 1021. Compared with the method of directly introducing the two gases into the heating container, the chemical reaction effect is better. Since the valve of the pretreatment pipeline is in a closed state at this time, the mixed gas can only enter the mixing barrel 202, and then pass through the stirring mechanism 203 into the two outlet pipes 204, and finally be sprayed onto the wafer from the multiple jet holes 206 on the nozzle 205. The epitaxial gas undergoes a chemical reaction in a high-temperature environment and is deposited on the surface of the wafer. At the same time, the doping gas also undergoes a chemical reaction in a high-temperature environment and is deposited on the surface of the wafer. The two substances together form an epitaxial layer on the surface of the wafer, and the epitaxial layer can improve the performance of the wafer.

[0055] Embodiment 2 In actual use, it was found that although the four-way tube 201 can make the two gases collide and perform preliminary mixing, and then the mixed gas enters the heating chamber 1021 through the mixing cylinder 202, due to the short length of the mixing cylinder 202, the mixed gas can directly pass through the mixing cylinder 202, and it is difficult to achieve uniform mixing of the gases. Further improvements are made on the basis of the above embodiments.

[0056] See also Figure 3 and Figure 4 As shown, a spiral plate 4 is provided in the mixing drum 202, and the stirring mechanism 203 includes a stirring barrel 2031 connected to the mixing barrel 202, and a stirring shaft 2032 is rotatably connected in the stirring barrel 2031. The stirring shaft 2032 is provided with a plurality of stirring rods 2033 evenly distributed along the circumferential direction on the upper and lower sides, and the stirring rods 2033 on the upper and lower sides are staggered, and each stirring rod 2033 is provided with a plurality of vertical rods 2034 perpendicular to it.

[0057] See also Figure 2 , Figure 6 , Fig.11 and Fig.12 As shown, a sleeve 6 is provided on the top of the rotating shaft 301 and is located below the stirring shaft 2032. A plurality of slots 7 evenly distributed along the circumferential direction are provided on the inner surface of the sleeve 6. The slots 7 gradually widen toward the stirring shaft 2032. A plurality of plug-in blocks 8 that can be inserted into the slots 7 are provided at the lower part of the stirring shaft 2032.

[0058] On the basis of the above embodiment, when the rotating shaft 301 moves upward with the lifting platform 103, the sleeve 6 moves upward with the rotating shaft 301, and the distance between the sleeve 6 and the stirring shaft 2032 gradually decreases until the slot 7 in the sleeve 6 contacts the plug 8 on the stirring shaft 2032. Since the slot 7 gradually widens toward the direction approaching the stirring shaft 2032, the plug 8 can be smoothly inserted into the slot 7 and finally enter the bottom of the slot 7. Each plug 8 is located at the bottom of the slot 7 on the corresponding side. When the motor 3022 drives the rotating shaft 301 to rotate, the rotating shaft 301 drives the sleeve 6 to rotate, and the sleeve 6 drives the stirring shaft 2032 to rotate, thereby making full use of the power of the motor 3022.

[0059] The epitaxial gas and the doping gas collide and mix together in the four-way pipe 201, and the mixed gas enters the mixing barrel 202. Since the mixing barrel 202 is provided with a spiral plate 4, the mixed gas cannot directly pass through the mixing barrel 202, and can only flow gradually toward the stirring mechanism 203 along the spiral shape of the surface of the spiral plate 4. The spiral plate 4 extends the path length of the mixed gas through the mixing barrel 202, so that the mixed gas can spirally flow in the mixing barrel 202 and be mixed to a certain extent again, thereby enhancing the mixing effect.

[0060] The mixed gas passes through the mixing barrel 202 and enters the stirring barrel 2031 in the stirring mechanism 203. The stirring shaft 2032 drives multiple stirring rods 2033 to rotate. Each stirring rod 2033 drives multiple vertical rods 2034 to rotate around the stirring shaft 2032. The multiple vertical rods 2034 can expand the range of action of the stirring rod 2033, and the stirring rods 2033 on the upper and lower sides are staggered, which can stir the mixed gas in the stirring barrel 2031 so that the mixed gas can be evenly mixed. The evenly mixed gas enters the nozzle 205 from the outlet pipe 204, and is finally sprayed onto the wafer from the multiple jet holes 206, and an epitaxial layer is grown on the wafer.

[0061] Embodiment 3 It was found in actual use that although the two gases can be mixed evenly through the above mechanism to make the mixed gas meet the requirements, during the growth of the epitaxial layer, the wafer on the tray 304 only rotates with the base 303, and the relative position of the wafer in the tray 304 does not change. It is difficult for the mixed gas to fully contact the surface of the wafer, and may not contact at some points, which can easily cause uneven distribution of the epitaxial layer. Further improvements are made on the basis of the above embodiments.

[0062] See also Fig. 9 and Fig.10 As shown, the base 303 is provided with a plurality of self-rotating mechanisms 5 corresponding one to one with the trays 304, and the self-rotating mechanisms 5 include a short shaft 501 rotatably connected to the base 303, one end of the short shaft 501 is fixed to the tray 304 on the corresponding side, and the other end is provided with a turntable 502, and a plurality of blades 503 evenly distributed along the circumferential direction are provided on the side of the turntable 502, and a plurality of through grooves 504 located around the short shaft 501 are opened on the base 303, and each through groove 504 corresponds to a plurality of blades 503 on the corresponding side.

[0063] On the basis of the above embodiment, when the mixed gas is sprayed onto the wafer from the multiple jet holes 206, part of the mixed gas and the waste gas generated after the chemical reaction flows out from around the wafer, and then enters the through grooves 504 around the wafer, and the gas acts on the multiple blades 503 corresponding to the through grooves 504. The multiple blades 503 are affected by the wind force generated by the gas flow, and the multiple blades 503 begin to drive the turntable 502 to rotate, and the turntable 502 drives the short shaft 501 to rotate, and the short shaft 501 drives the tray 304 fixed thereto to rotate, and the tray 304 drives the wafer to rotate around the short shaft 501, that is, the wafer rotates while rotating with the base 303, so that the mixed gas can be in uniform contact with the wafer, so that the thickness of the grown epitaxial layer is more uniform, and the doping material is evenly distributed, thereby overcoming the defects caused by uneven gas mixing and improving the performance of the wafer through a uniform epitaxial layer.

[0064] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for producing high-resistance epitaxial wafers on heavily phosphorus-doped substrates, comprising a device body (1), wherein the device body (1) comprises a housing (101), characterized in that: A heating mechanism (102) is provided in the upper part of the outer shell (101), and a lifting platform (103) located below the heating mechanism (102) is provided in the outer shell (101); A gas mixing section (2), the gas mixing section (2) comprising a four-way pipe (201), a mixing barrel (202) being provided at one end of the four-way pipe (201), a stirring mechanism (203) being provided at the free end of the mixing barrel (202), two symmetrically distributed gas outlet pipes (204) being provided at the lower part of the stirring mechanism (203), a plurality of nozzles (205) being provided on the gas outlet pipes (204), and a plurality of gas injection holes (206) being provided on the nozzles (205); A placement portion (3), the placement portion (3) comprising a rotating shaft (301) rotatably connected to the lifting platform (103), the rotating shaft (301) being driven by a driving mechanism (302), a base (303) located above the lifting platform (103) being provided on the rotating shaft (301), a plurality of trays (304) being provided on the side of the base (303), each of the trays (304) being capable of aligning with a nozzle (205) on a corresponding side; When the driving mechanism (302) drives the rotating shaft (301) to rotate, the stirring mechanism (203) can rotate along with the rotating shaft (301).

2. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 1, characterized in that: The heating mechanism (102) comprises a heating cavity (1021) with an opening facing downwards, the heating cavity (1021) is made of quartz material, and a heating coil (1022) is provided between the heating cavity (1021) and the housing (101).

3. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 2, characterized in that: The lifting platform (103) comprises a lifting plate (1031), the lifting plate (1031) is made of quartz material, the lifting plate (1031) is capable of covering the opening at the bottom of the heating cavity (1021), and a plurality of electric telescopic rods (1032) distributed in a rectangular array are provided at the bottom of the lifting plate (1031).

4. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 3, characterized in that: The mixing drum (202) is provided with a spiral plate (4), the stirring mechanism (203) comprises a stirring barrel (2031) connected to the mixing drum (202), a stirring shaft (2032) rotatably connected to the stirring barrel (2031), a plurality of stirring rods (2033) evenly distributed along the circumferential direction are provided on both upper and lower sides of the stirring shaft (2032), and the stirring rods (2033) on the upper and lower sides are staggered, and each stirring rod (2033) is provided with a plurality of vertical rods (2034) perpendicular to the stirring rod (2033).

5. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 4, characterized in that: The driving mechanism (302) comprises a support plate (3021) fixed to the lifting plate (1031), a motor (3022) being provided on the support plate (3021), and an output end of the motor (3022) being fixed to the rotating shaft (301).

6. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 5, characterized in that: The base (303) is provided with a plurality of self-rotating mechanisms (5) corresponding one to one with the trays (304), the self-rotating mechanisms (5) comprising a short shaft (501) rotatably connected to the base (303), one end of the short shaft (501) being fixed to the tray (304) on the corresponding side, and the other end being provided with a turntable (502), a side surface of the turntable (502) being provided with a plurality of blades (503) evenly distributed along a circumferential direction, the base (303) being provided with a plurality of through slots (504) located around the short shaft (501), each of the through slots (504) corresponding to a plurality of blades (503) on the corresponding side.

7. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 6, characterized in that: A sleeve (6) located below the stirring shaft (2032) is provided at the top of the rotating shaft (301); a plurality of slots (7) evenly distributed along the circumferential direction are provided on the inner surface of the sleeve (6); the slots (7) gradually widen towards the stirring shaft (2032); and a plurality of inserts (8) capable of being inserted into the slots (7) are provided at the bottom of the stirring shaft (2032).

8. The equipment for producing high resistance epitaxial wafers on heavily phosphorus-doped substrates according to claim 7, characterized in that: The base (303) is in the shape of a polygonal cone that is smaller at the top and larger at the bottom. A plurality of through holes (9) are provided at the bottom of the base (303).

9. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 8, characterized in that: The lower part of the housing (101) is provided with two symmetrically distributed material holes (10).

10. The equipment for producing high resistance epitaxial wafers with heavily phosphorus-doped substrates according to claim 9, characterized in that: A first joint (11), a second joint (12) and a third joint (13) are provided on the top of the housing (101); the first joint (11), the second joint (12) and the third joint (13) are respectively connected to the other three ends of the four-way pipe (201).

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