Anti-deviation device of ion implanter

Abstract

The invention discloses an anti-deviation device of an ion implanter, and relates to the technical field of ion implanters, the anti-deviation device comprises a process cavity mounting bracket and a target table arranged on the process cavity mounting bracket, and a rotary driving part is fixedly mounted on the process cavity mounting bracket. According to the anti-deviation device of the ion implanter, the pressurized low-temperature gas is injected into the target table through the pressurized gas conveying piece, a silicon wafer on the target table is cooled in a heat conduction mode, and negative pressure generated in the gas flowing process serves as a driving source to drive the silicon wafer positioning assembly to clamp and position the silicon wafer; therefore, when the rotary driving part drives the target table to rotate, anti-deviation protection of the silicon wafer is achieved, meanwhile, under the arrangement of the silicon wafer supporting assembly, when the silicon wafer is fed, a certain distance is reserved between the silicon wafer and the target table, feeding and discharging of a mechanical arm are facilitated, when ions are injected into the silicon wafer, full contact of the silicon wafer and the target table is guaranteed, and a guarantee is provided for cooling of the silicon wafer.

Description

Technical Field

[0001] The present invention relates to the technical field of ion implanters, and particularly to an anti-offset device for an ion implanter. Background Art

[0002] The working principle of an ion implanter mainly involves four key processes: ion generation, ion acceleration, ion transmission, and ion implantation. Among them, the ion implantation process is that the ion beam after acceleration and transmission directly bombards the surface of the material to be implanted. The ions will penetrate the surface layer of the material, collide with the atoms in the material, and finally stay at a certain depth inside the material, thereby changing the properties of the material.

[0003] When ion implanting a silicon wafer in the process chamber of an ion implanter, the existing silicon wafers often rely on a manipulator for intelligent picking and placing in and out of the process chamber. Although its positioning is accurate, due to the rotation of the target table, it is necessary to position the silicon wafer to prevent offset to ensure the processing quality of the silicon wafer. For example, an anti-offset device for an ion implanter described in Application No. 202322131572.0, through the cooperation of a fastening component and a clamping component, further prevents the silicon wafer from loosening and offsetting when rotating on a hollow cylinder, improves the success rate of silicon wafer processing, and can also be used for silicon wafers of different sizes, avoiding replacing its clamping component due to silicon wafers of different sizes. However, it lacks cooling for the silicon wafer during the ion implantation process.

[0004] During the ion implantation process, due to the collision of high-energy ion beams with the silicon wafer, a large amount of heat will be generated, which may cause the temperature of the silicon wafer to rise to 100°C or above. This temperature rise will cause problems such as doping distribution offset, increased lattice damage, and photoresist deformation. It is very necessary to perform real-time cooling. Currently, low-temperature gas is blown to the back of the silicon wafer through a helium nozzle, and the high thermal conductivity of helium is used for rapid heat conduction. Since the helium nozzle blows air directly to the back of the silicon wafer, it is easy to affect the stability of the silicon wafer and is also easy to interfere with the ion beam current.

[0005] Based on the retrieval of the above information, it can be seen that during the ion implantation process into a silicon wafer, when using helium back blowing to cool the silicon wafer, there is a risk of interfering with the ion beam current, and the silicon wafer is also prone to offset during rotation. Therefore, an anti-offset device for an ion implanter is specifically proposed to achieve convenient cooling of the silicon wafer while ensuring anti-offset of the silicon wafer, providing a reliable guarantee for the continuous ion implantation work of a large number of silicon wafers. Summary of the Invention

[0006] Aiming at the deficiencies of the prior art, the present invention provides an anti-offset device for an ion implanter, which solves the problem that the silicon wafer is prone to offset during the ion implantation process into the silicon wafer.

[0007] To achieve the above object, the present invention is realized through the following technical solutions: An anti-deviation device for an ion implanter, including a process chamber mounting bracket and a target table disposed on the process chamber mounting bracket. A rotation driving member is fixedly installed on the process chamber mounting bracket, and the rotation driving member is used to drive the target table to rotate. A wafer positioning component and a wafer support component are disposed inside the target table. A pressurized gas delivery member is disposed on the process chamber mounting bracket, and the pressurized gas delivery member is used in cooperation with the target table, the wafer positioning component, and the wafer support component respectively;

[0008] The pressurized gas delivery member includes a gas guide ring cover and a gas guide main pipe. One end of the gas guide main pipe is communicated with a U-shaped pipe, and both ends of the U-shaped pipe are fixedly communicated with both sides of the gas guide ring cover;

[0009] The target table includes a heat conducting plate and a bottom plate. Three sets of isolation members are fixedly installed between the heat conducting plate and the bottom plate. The three sets of isolation members are evenly spaced in a circumferential distribution, and both the heat conducting plate and the bottom plate are rotatably installed inside the gas guide ring cover. An exhaust pipe is also communicated with the bottom of the bottom plate.

[0010] In order to construct a gas passing cavity in the target table and provide an installation space for the wafer positioning component, the present invention is further configured as follows: Each of the three sets of isolation members includes an upper housing and a lower housing. A first piston cavity and a second piston cavity which are used in cooperation are respectively opened on one side of the upper housing and the lower housing which face each other. A semi-circular hole is opened between the first piston cavity and the second piston cavity;

[0011] The top of the upper housing is fixedly connected to the bottom of the heat conducting plate, and the bottom of the lower housing is fixedly connected to the top of the bottom plate. The upper housing and the lower housing are fixedly connected by welding.

[0012] In order to achieve convenient and stable clamping of the wafer to avoid the situation of wafer deviation during rotation, the present invention is further configured as follows: Each of the three wafer positioning components includes a piston plate and a negative pressure pipe. A push rod is fixedly connected to one side of the piston plate. One end of the push rod is fixedly connected to a plugging seat, and a clamping rod is fixedly plugged on the top of the plugging seat;

[0013] The piston plate is slidably installed inside the two first piston cavities. A first spring is disposed between the other side of the piston plate and one side of the inner cavity of the first piston cavity. The push rod is slidably installed between the two semi-circular holes, and the plugging seat is slidably installed between the two second piston cavities;

[0014] Three grooves are opened on the top of the heat conducting plate. An activity port communicated with the second piston cavity is opened at the bottom of the groove. The top of the plugging seat passes through the activity port and extends into the groove. A sealing plate is fixedly connected to the top of the outer circumference of the plugging seat, and the sealing plate is in sliding contact with the inner surface of the groove.

[0015] In order to create a negative pressure environment in the negative pressure pipe, the present invention is further configured as follows: One end of each of the three negative pressure pipes is communicated with the first piston chamber, and the other end of the negative pressure pipe penetrates through the bottom plate and is communicated with the exhaust pipe, wherein the axis of the negative pressure pipe forms an angle of 35°-45° with the axis of the exhaust pipe.

[0016] In order to conveniently support the silicon wafer and provide convenient conditions for the intelligent picking and placing of the silicon wafer by the manipulator, the present invention is further configured as follows: The silicon wafer support assembly includes a support plate, a support rod is fixedly connected to the bottom of the support plate, a flow-dividing piston block is fixedly connected to the bottom end of the support rod, and three groups of first chutes and three groups of second chutes are evenly spaced on the outer periphery of the flow-dividing piston block, and the first chutes and the second chutes are arranged alternately;

[0017] An embedding groove is formed in the top of the heat conducting plate, the embedding groove is communicated with the three grooves respectively, and the embedding groove is used in cooperation with the support plate. The bottom end of the support rod penetrates through the heat conducting plate and extends into the exhaust pipe;

[0018] The flow-dividing piston block is slidably installed inside the exhaust pipe. Three groups of guiding sliding plates and three groups of temporary blocking plates are fixedly installed on the inner wall of the exhaust pipe at equal intervals. The guiding sliding plates and the temporary blocking plates are arranged alternately. The guiding sliding plates are slidably matched with the first chutes, and the temporary blocking plates are slidably matched with the second chutes.

[0019] In order to ensure the effective reset of the support plate, the present invention is further configured as follows: The three groups of temporary blocking plates are all arranged directly above the connection between the negative pressure pipe and the exhaust pipe. The bottom ends of the three groups of guiding sliding plates are fixedly connected to a three-sided bracket. The three-sided bracket is arranged below the negative pressure pipe. An auxiliary rod is fixedly connected to the bottom of the flow-dividing piston block. The bottom end of the auxiliary rod penetrates through the three-sided bracket and is fixedly connected to a limiting block. A second spring is further sleeved on the outer periphery of the auxiliary rod. The two ends of the second spring are respectively in contact with the bottom of the flow-dividing piston block and the top of the three-sided bracket.

[0020] In order to avoid excessive displacement when the negative pressure drives the silicon wafer positioning assembly to perform the clamping and positioning work and provide stable support for the clamping and positioning of silicon wafers of different sizes, the present invention is further configured as follows: A limiting and protecting member is further arranged between the heat conducting plate and the bottom plate. The limiting and protecting member includes a rotating ring and an adjusting gear. Three groups of inclined grooves are evenly spaced on the outer periphery of the rotating ring. Three groups of pin posts are slidably installed in the three groups of inclined grooves. The bottom end of the pin post is fixedly connected to a limiting plate. One end of the limiting plate penetrates through the upper shell and the lower shell and extends into the first piston chamber;

[0021] A number of teeth are fixedly installed at the bottom of the outer periphery of the swivel ring and between the open ends of the two inclined slots. The number of teeth are meshed and cooperated with the adjusting gear. The adjusting gear is arranged between the heat conducting plate and the bottom plate. The bottom connecting rod of the adjusting gear penetrates through the bottom plate and is fixedly installed with an internal hexagonal cap. The bottom of the bottom plate is threadedly installed with a fastening bolt through a connecting plate. One end of the fastening bolt is in contact with the outer periphery of the internal hexagonal cap.

[0022] In order to realize the rotation drive of the silicon wafer, the present invention is further arranged as follows: The rotation drive member includes a servo motor. The output end of the servo motor is fixedly connected with a driving gear through a coupling. The outer periphery of the exhaust pipe is sleeved and fixedly connected with a driven gear, and the driving gear is meshed and cooperated with the driven gear;

[0023] The servo motor is fixedly installed on the process chamber mounting bracket. The bottom end of the exhaust pipe penetrates through the process chamber mounting bracket and extends below the process chamber mounting bracket.

[0024] In order to ensure the airtightness between the pressurized gas delivery member and the target table, the present invention is further arranged as follows: First sealing grooves are respectively opened on the opposite sides of the heat conducting plate and the bottom plate. Second sealing grooves communicating with the two first sealing grooves are respectively opened at the top and bottom of the inner cavity of the air guide ring cover. First sealing gaskets are fixedly connected inside the two second sealing grooves, and the first sealing gaskets are used in cooperation with the first sealing grooves. A number of reinforcing rubber columns are also fixedly installed on the opposite sides of the two first sealing gaskets. The reinforcing rubber columns are arranged inside the air guide ring cover.

[0025] In order to further ensure the airtightness between the pressurized gas delivery member and the target table, the present invention is further arranged as follows: Reinforcing rings are fixedly installed on the outer peripheries of the top and bottom of the air guide ring cover. The top of the heat conducting plate and the bottom of the bottom plate are respectively fixedly installed with outward-turning covers through bolts. The opposite sides of the two outward-turning covers are respectively in contact with the opposite sides of the two reinforcing rings, and a second sealing gasket is arranged between the reinforcing ring and the outward-turning cover.

[0026] The present invention provides an anti-deviation device for an ion implanter. It has the following beneficial effects:

[0027] (1) In the present invention, pressurized low-temperature gas is injected into the target table through the pressurized gas delivery member to cool the silicon wafer on the target table by means of heat conduction. The negative pressure generated during the gas flow is used as a driving source to drive the silicon wafer positioning assembly to clamp and position the silicon wafer. In this way, when the rotation drive member drives the target table to rotate, anti-deviation protection of the silicon wafer is realized. At the same time, under the setting of the silicon wafer support assembly, when the silicon wafer is loaded, a certain distance is left between the silicon wafer and the target table, which is convenient for the manipulator to load and unload. When ions are implanted into the silicon wafer, full contact between the silicon wafer and the target table is ensured, providing guarantee for the cooling of the silicon wafer.

[0028] (2) By setting a negative pressure pipe at a certain angle with the exhaust pipe, when the pressurized gas flows through the exhaust pipe, negative pressure is generated in the negative pressure pipe to adsorb the piston plate to move, thereby ensuring the clamping and positioning of the silicon wafer by the three clamping rods. And with the setting of the limit protection member, the moving distance of the piston plate is limited, avoiding the situation that the silicon wafer is damaged due to excessive displacement of the piston plate caused by strong negative pressure. At the same time, the clamping accuracy of the silicon wafer can be guaranteed, and by adjusting the limit protection member, the limit of different moving distances of the piston plate is realized, providing support for the clamping and positioning of silicon wafers of different sizes.

[0029] (3) By setting the shunt piston block, the first chute, the second chute, the guiding slide plate and the temporary blocking plate, the stable lifting of the shunt piston block is ensured by the guiding slide plate, and thus the stable lifting of the silicon wafer is ensured. Driven by the pressurized air, the shunt piston block is driven to descend. When the shunt piston block disengages from the temporary blocking plate, the flow channel cross-section formed by the three second chutes is much smaller than the flow channel cross-section of the exhaust pipe, and the pressurized air accelerates through the second chutes. According to the Venturi effect, the intensity and stability of the negative pressure in the negative pressure pipe are further ensured. Description of the Drawings

[0030] Figure 1 is the external structure schematic diagram of the present invention;

[0031] Figure 2 is the external structure schematic diagram of the present invention from the bottom view;

[0032] Figure 3 is the structure schematic diagram of the pressurized gas delivery member of the present invention;

[0033] Figure 4 is the structure schematic diagram of the target table of the present invention;

[0034] Figure 5 is the connection schematic diagram of the heat conducting plate and the upper housing structure of the present invention;

[0035] Figure 6 is the connection schematic diagram of the bottom plate, the lower housing, the silicon wafer positioning component, the adjusting gear, the hexagon socket head cap and the fastening bolt structure of the present invention;

[0036] Figure 7 is the connection schematic diagram of the piston plate, the push rod, the socket and the plugging plate structure of the present invention;

[0037] Figure 8 is the connection schematic diagram of the bottom plate, the lower housing and the limit protection member structure of the present invention;

[0038] Figure 9 is the structure schematic diagram of the heat conducting plate, the bottom plate, the air guide ring cover, the first sealing gasket, the reinforcing rubber column and the reinforcing ring of the present invention;

[0039] Figure 10 This is a schematic structural diagram of the heat-conducting plate, bottom plate, outer-turned cover, air-guide ring cover, strengthening ring and second sealing washer of the present invention;

[0040] Figure 11 This is a schematic structural diagram of the silicon wafer support assembly of the present invention;

[0041] Figure 12 This is an unfolded schematic diagram of the silicon wafer support assembly of the present invention;

[0042] Figure 13 This is a schematic internal structure diagram of the present invention.

[0043] In the figure:

[0044] 1. Process chamber mounting bracket;

[0045] 2. Target table; 201. Heat-conducting plate; 202. Bottom plate; 203. Isolator; 2031. Upper housing; 2032. Lower housing; 2033. First piston chamber; 2034. Second piston chamber; 2035. Semi-circular hole; 204. Exhaust pipe; 205. Groove; 206. Movable port; 207. Embedding groove; 208. First sealing groove; 209. Outer-turned cover;

[0046] 3. Rotation driving part; 301. Servo motor; 302. Driving gear; 303. Driven gear;

[0047] 4. Silicon wafer positioning assembly; 401. Piston plate; 402. Negative pressure pipe; 403. Push rod; 404. Plug-in socket; 405. Clamping rod; 406. Sealing plate; 407. First spring;

[0048] 5. Silicon wafer support assembly; 501. Support plate; 502. Support rod; 503. Shunt piston block; 504. First chute; 505. Second chute; 506. Guide sliding plate; 507. Temporary blocking plate; 508. Three-side bracket; 509. Auxiliary rod; 5010. Limit block; 5011. Second spring;

[0049] 6. Pressurized gas delivery part; 601. Air-guide ring cover; 602. Air-guide main pipe; 603. U-shaped pipe; 604. Second sealing groove; 605. First sealing washer; 606. Reinforcing rubber column; 607. Strengthening ring; 608. Second sealing washer;

[0050] 7. Limit protection part; 701. Rotating ring; 702. Adjusting gear; 703. Inclined groove; 704. Pin column; 705. Limit plate; 706. Teeth; 707. Hexagon socket head cap; 708. Fastening bolt. Detailed implementation manners

[0051] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0052] Please refer to Figures 1-13 , the embodiments of the present invention provide the following technical solutions:

[0053] Embodiment 1

[0054] An anti-deviation device for an ion implanter, including a process chamber mounting bracket 1, and a target table 2, a rotation driving member 3, a wafer positioning assembly 4, a pressurized gas delivery member 6, and a limit protection member 7 provided on the process chamber mounting bracket 1.

[0055] As a preferred solution, when the wafer is placed on the target table 2, in order to use the target table 2 to cool the wafer, on the basis that the target table 2 needs to rotate, the target table 2 is designed with a cavity. Specifically, the target table 2 includes a heat conduction plate 201 and a bottom plate 202. Three sets of isolation members 203 are fixedly installed between the heat conduction plate 201 and the bottom plate 202. The three sets of isolation members 203 are evenly spaced and distributed in a circular pattern. The bottom of the bottom plate 202 is also communicated with an exhaust pipe 204. The bottom end of the exhaust pipe 204 penetrates through the process chamber mounting bracket 1 and extends below the process chamber mounting bracket 1. In order to achieve vertical limitation of the exhaust pipe 204, a limit ring is sleeved on the outer periphery of the exhaust pipe 204, and the bottom of the limit ring is in contact with the top of the process chamber mounting bracket 1 to achieve the effect of vertical limitation. Among them, under the support of the three sets of isolation members 203, a certain cavity is left between the heat conduction plate 201 and the bottom plate 202. When pressurized helium gas enters from the cavity, it can be discharged from the exhaust pipe 204.

[0056] As a preferred solution, in order to achieve the overall rotation of the target table 2 so that ions can be evenly implanted into the wafer, the rotation driving member 3 includes a servo motor 301. The servo motor 301 is electrically connected to an external power supply and is controlled by a control switch. The servo motor 301 is fixedly installed on the process chamber mounting bracket 1. The output end of the servo motor 301 is fixedly connected with a driving gear 302 through a coupling. A driven gear 303 is sleeved and fixedly connected on the outer periphery of the exhaust pipe 204, and the driving gear 302 is meshed and matched with the driven gear 303.

[0057] As a preferred solution, in order to achieve the pressurized helium gas to be transported from the cavity during rotation, the pressurized gas delivery member 6 of the pressurized helium gas includes a gas guiding ring cover 601 and a main gas guiding pipe 602. One end of the main gas guiding pipe 602 is connected to a U-shaped pipe 603, and the other end of the main gas guiding pipe 602 is provided with a docking flange for convenient docking with an external helium gas supply device. It should be noted that the external helium gas supply device has a pressure regulating structure to facilitate the input of pressurized helium gas into the main gas guiding pipe 602. The two ends of the U-shaped pipe 603 are respectively connected and fixed to both sides of the gas guiding ring cover 601, and the heat conducting plate 201 and the bottom plate 202 are both rotatably installed inside the gas guiding ring cover 601. In order to ensure the airtightness at the connection between the heat conducting plate 201 and the bottom plate 202 and the gas guiding ring cover 601, encryption treatment is carried out in a double-sealing manner, specifically including:

[0058] First seal: First sealing grooves 208 are respectively formed on the opposite sides of the heat conducting plate 201 and the bottom plate 202. Second sealing grooves 604 communicating with the two first sealing grooves 208 are respectively formed at the top and bottom of the inner cavity of the gas guiding ring cover 601. First sealing gaskets 605 are fixedly connected inside the two second sealing grooves 604, and the first sealing gaskets 605 are used in cooperation with the first sealing grooves 208. A number of reinforcing rubber columns 606 are also fixedly installed on the opposite sides of the two first sealing gaskets 605, and the reinforcing rubber columns 606 are arranged inside the gas guiding ring cover 601;

[0059] Second seal: Reinforcing rings 607 are fixedly installed on the outer circumferences of the top and bottom of the gas guiding ring cover 601. Outer turning covers 209 are fixedly installed on the top of the heat conducting plate 201 and the bottom of the bottom plate 202 through bolts. The opposite sides of the two outer turning covers 209 are respectively in contact with the opposite sides of the two reinforcing rings 607, and a second sealing gasket 608 is arranged between the reinforcing ring 607 and the outer turning cover 209.

[0060] The above-mentioned pressurized helium gas cools the target table 2 through the cavity. The target table 2 cools the silicon wafer by means of heat conduction, and the pressurized helium gas after heat exchange is discharged from the exhaust pipe 204.

[0061] Further explanation: To prevent the silicon wafer from shifting on the target table 2, the three sets of spacers 203 each include an upper housing 2031 and a lower housing 2032. The top of the upper housing 2031 is fixedly connected to the bottom of the heat conducting plate 201, and the bottom of the lower housing 2032 is fixedly connected to the top of the bottom plate 202. The upper housing 2031 and the lower housing 2032 are fixedly connected by welding. On the opposite sides of the upper housing 2031 and the lower housing 2032, a first piston chamber 2033 and a second piston chamber 2034 are respectively provided for mating use. A semi-circular hole 2035 is provided between the first piston chamber 2033 and the second piston chamber 2034. Each of the three silicon wafer positioning components 4 includes a piston plate 401 and a negative pressure tube 402. The piston plate 401 is slidably installed inside the two first piston chambers 2033. And, to facilitate the reset of the piston plate 401, a first spring 407 is provided between the other side of the piston plate 401 and one side of the inner cavity of the first piston chamber 2033. One side of the piston plate 401 is fixedly connected to a push rod 403. The push rod 403 is slidably installed between the two semi-circular holes 2035. One end of the push rod 403 is fixedly connected to a plug-in seat 404. A clamping rod 405 is fixedly plugged on the top of the plug-in seat 404. The plug-in seat 404 is slidably installed between the two second piston chambers 2034. Three grooves 205 are provided on the top of the heat conducting plate 201. An activity port 206 communicating with the second piston chamber 2034 is provided at the bottom of the groove 205. The top of the plug-in seat 404 passes through the activity port 206 and extends into the groove 205. A sealing plate 406 is fixedly connected to the top of the outer periphery of the plug-in seat 404. And the sealing plate 406 is in sliding contact with the inner surface of the groove 205. At this time, as long as the three piston plates 401 are pulled to move, the clamping rod 405 can clamp and position the silicon wafer on the heat conducting plate 201. On the basis that the pressurized helium gas is discharged from the exhaust pipe 204, one end of each of the three negative pressure tubes 402 is communicated with the first piston chamber 2033. The other end of the negative pressure tube 402 penetrates through the bottom plate 202 and is communicated with the exhaust pipe 204. The included angle between the axis of the negative pressure tube 402 and the axis of the exhaust pipe 204 is 35° - 45°. At this time, the pressurized helium gas flows out at an accelerated speed in the exhaust pipe 204. When passing through the connection between the negative pressure tube 402 and the exhaust pipe 204, a negative pressure will be generated in the negative pressure tube 402 to adsorb the piston plate 401 to move, thereby providing a power driving condition for the clamping and positioning of the silicon wafer. Specifically, when the piston plate 401 moves, the plug-in seat 404 is pulled to move in the activity port 206 through the push rod 403. The plug-in seat 404 drives the clamping rod 405 to move towards the silicon wafer. When all three clamping rods 405 are in contact with the outer periphery of the silicon wafer, the clamping and positioning of the silicon wafer is completed.

[0062] As a preferred solution, in order to avoid uneven negative pressures in the three negative pressure tubes 402, which may cause the three piston plates 401 to move out of sync and pose a risk of offset in the clamping center position of the silicon wafer, a limit and protection member 7 is further provided between the heat conducting plate 201 and the bottom plate 202. Specifically, the limit and protection member 7 includes a rotating ring 701 and an adjusting gear 702. Three groups of inclined slots 703 are evenly spaced on the outer periphery of the rotating ring 701. A pin 704 is slidably installed in each of the three groups of inclined slots 703. The bottom end of the pin 704 is fixedly connected to a limit plate 705. One end of the limit plate 705 penetrates through the upper housing 2031 and the lower housing 2032 and extends into the first piston chamber 2033. A plurality of teeth 706 are fixedly installed at the bottom of the outer periphery of the rotating ring 701 and between the open ends of two inclined slots 703. The plurality of teeth 706 are engaged with the adjusting gear 702. The adjusting gear 702 is arranged between the heat conducting plate 201 and the bottom plate 202. The bottom connecting rod of the adjusting gear 702 penetrates through the bottom plate 202 and is fixedly installed with an internal hexagonal cap 707. Among them, in order to ensure the airtightness of the cavity, on the basis of ensuring the rotation of the adjusting gear 702, the connection between the bottom connecting rod of the adjusting gear 702 and the bottom plate 202 is sealed. The bottom of the bottom plate 202 is threadedly installed with a fastening bolt 708 through a connecting plate. One end of the fastening bolt 708 contacts the outer periphery of the internal hexagonal cap 707 and is used to limit and fix the internal hexagonal cap 707 when the internal hexagonal cap 707 completes the rotation adjustment.

[0063] During use, the internal hexagonal cap 707 is rotated to make the adjusting gear 702 rotate, and then the teeth 706 are driven to make the rotating ring 701 rotate. During this process, the pin 704 is extruded by the inclined slot 703 to adjust the depth of insertion of the limit plate 705 into the first piston chamber 2033. Among them, the moving distances of the three limit plates 705 are equal, that is, the limiting distances for the movement of the piston plate 401 are equal. When the diameter of the circle formed by the outer edges of the three limit plates 705 is the same as or slightly smaller than the diameter of the silicon wafer, the situation of excessive displacement of the piston plate 401 can be avoided, thereby ensuring the clamping accuracy of the silicon wafer. And after adjusting the depth of insertion of the limit plate 705 into the first piston chamber 2033, it is adapted to the clamping and positioning of silicon wafers of different sizes.

[0064] In this embodiment, the flow of pressurized helium gas is utilized to cool the silicon wafer, and pressurized helium gas is used as the power source to realize the clamping and positioning of the silicon wafer, which can effectively prevent the silicon wafer from offsetting due to rotation during the ion implantation process.

[0065] Embodiment Two

[0066] As an improvement over the previous embodiment, an anti-offset device for an ion implanter further includes a wafer support assembly 5. The wafer support assembly 5 includes a support plate 501. A support rod 502 is fixedly connected to the bottom of the support plate 501. An embedding groove 207 is formed at the top of the heat conduction plate 201. The embedding groove 207 communicates with three grooves 205 respectively, and the embedding groove 207 is used in cooperation with the support plate 501. The bottom end of the support rod 502 penetrates through the heat conduction plate 201 and extends into the exhaust pipe 204. Among them, the support rod 502 penetrates through the embedding groove 207. In order to ensure the airtightness of the connection between the support rod 502 and the heat conduction plate 201 during the lifting of the support rod 502, a sealing treatment is performed at the connection between the support rod 502 and the heat conduction plate 201. A sealing sleeve is fixedly arranged at the outer periphery of the support rod 502 and at the bottom of the heat conduction plate 201. It should be noted that the sealing sleeve is arranged inside the rotating ring 701, that is, the rotating ring 701 is designed to be sleeved outside the support rod 502. The bottom end of the support rod 502 is fixedly connected with a flow dividing piston block 503. Three groups of first sliding grooves 504 and three groups of second sliding grooves 505 are evenly spaced on the outer periphery of the flow dividing piston block 503, and the first sliding grooves 504 and the second sliding grooves 505 are arranged alternately. The flow dividing piston block 503 is slidably installed inside the exhaust pipe 204. Three groups of guiding sliding plates 506 and three groups of temporary blocking plates 507 are fixedly installed on the inner wall of the exhaust pipe 204 at equal intervals. The guiding sliding plates 506 and the temporary blocking plates 507 are arranged alternately. The guiding sliding plates 506 are slidably matched with the first sliding grooves 504, and the temporary blocking plates 507 are slidably matched with the second sliding grooves 505. Among them, the guiding sliding plates 506 play a role in vertically guiding the flow dividing piston block 503, and the temporary blocking plates 507 play a role in temporary blocking, so that the pressurized helium gas can drive the flow dividing piston block 503 to move downward along the guiding sliding plates 506. Further explanation, in order to ensure that the support plate 501 is higher than the heat conduction plate 201 by a certain distance when no pressurized helium gas is applied, so as to facilitate the robot to pick and place the wafer, the bottom ends of the three groups of guiding sliding plates 506 are fixedly connected with a three-sided support 508. The three-sided support 508 is arranged below the negative pressure pipe 402. The bottom of the flow dividing piston block 503 is fixedly connected with an auxiliary rod 509. The bottom end of the auxiliary rod 509 penetrates through the three-sided support 508 and is fixedly connected with a limiting block 5010. The limiting block 5010 is used to ensure the maximum rising height of the support plate 501. A second spring 5011 is also sleeved on the outer periphery of the auxiliary rod 509. The two ends of the second spring 5011 are respectively in contact with the bottom of the flow dividing piston block 503 and the top of the three-sided support 508.

[0067] As a preferred solution, in order to ensure that there is sufficient negative pressure inside the negative pressure tube 402, three groups of temporary blocking plates 507 are arranged directly above the connection between the negative pressure tube 402 and the exhaust pipe 204. At this time, according to the Venturi effect, the corresponding cross-sectional area of ​​the three second slide grooves 505 is smaller than the cross-sectional area of ​​the exhaust pipe 204, the flow rate is increased, and the negative pressure value generated is also increased, so as to further ensure that sufficient negative pressure is generated in the negative pressure tube 402 to pull the piston plate 401 to move.

[0068] The advantage of the second embodiment over the first embodiment is that while the flow of pressurized helium is used to lift the support plate 501 to facilitate the placement of silicon wafers, sufficient negative pressure can be generated in the negative pressure tube 402 to ensure that the clamping rod 405 can stably clamp the silicon wafer.

[0069] When in use, after the manipulator places the silicon wafer on the support plate 501, the pressurized helium flows through the gas guide main pipe 602 through the U-shaped tube 603 into the cavity of the target platform 2, and then the pressurized helium enters the exhaust pipe 204, pushing the diverter piston block 503 to move downward along the guide slide plate 506 in the exhaust pipe 204. At the same time, the diverter piston block 503 drives the support rod 502 to move the support plate 501 downward, and the silicon wafer continues to fall. When the diverter piston block 503 is separated from the temporary blocking plate 507, the support plate 501 is completely immersed in the embedding groove 207, and the silicon wafer is in contact with the heat conducting plate 201.

[0070] When the pressurized helium passes through the second slide groove 505 and crosses the diverter piston block 503, negative pressure is generated in the negative pressure tube 402, and the piston plate 401 is sucked to move in the first piston chamber 2033 toward the limit plate 705. The piston plate 401 pulls the push rod 403 to move the socket 404, and the socket 404 drives the clamping rod 405 to move toward the silicon wafer. When the three clamping rods 405 are in contact with the periphery of the silicon wafer, the clamping and positioning of the silicon wafer is completed. At this time, the piston plate 401 is also in contact with the limit plate 705.

[0071] When the ion beam rushes toward the silicon wafer, the servo motor 301 is started, the servo motor 301 drives the driving gear 302 to rotate, the driving gear 302 drives the driven gear 303 to rotate the exhaust pipe 204, and the exhaust pipe 204 drives the target stage 2 and the silicon wafer to rotate synchronously;

[0072] After the ion implantation of the stamped silicon wafer is completed, the injection of pressurized ammonia is stopped, and the device is reset with the cooperation of the first spring 407 and the second spring 5011, that is, the support plate 501 lifts the silicon wafer for easy picking up by the robot.

[0073] As an extended explanation, in order to ensure the effective reset of the second spring 5011, a pressure relief pipe communicating with the cavity is connected to the bottom of the bottom plate 202. An electromagnetic control valve is provided on the surface of the pressure relief pipe. After the ion implantation of the silicon wafer is completed, the pressurized helium gas inside the cavity can be discharged by opening the electromagnetic control valve to ensure the smooth reset of the second spring 5011. Among them, the pressure relief pipe with an electromagnetic control valve on its surface is a conventional design and is not described in detail in the figure.

[0074] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An anti-deflection device for an ion implanter, comprising a process chamber mounting bracket (1) and a target table (2) arranged on the process chamber mounting bracket (1), characterized in that: A rotating driving member (3) is fixedly mounted on the process chamber mounting bracket (1), and the rotating driving member (3) is used to drive the target table (2) to rotate. A silicon wafer positioning assembly (4) and a silicon wafer supporting assembly (5) are arranged inside the target table (2). A pressurized gas conveying member (6) is arranged on the process chamber mounting bracket (1), and the pressurized gas conveying member (6) is used in conjunction with the target table (2), the silicon wafer positioning assembly (4) and the silicon wafer supporting assembly (5), respectively. The pressurized gas conveying member (6) comprises an air guide ring cover (601) and an air guide main pipe (602), one end of the air guide main pipe (602) is connected to a U-shaped pipe (603), and both ends of the U-shaped pipe (603) are respectively connected and fixed to two sides of the air guide ring cover (601); The target platform (2) comprises a heat conducting plate (201) and a base plate (202), three groups of isolating members (203) are fixedly installed between the heat conducting plate (201) and the base plate (202), the three groups of isolating members (203) are evenly spaced and distributed in a circle, and the heat conducting plate (201) and the base plate (202) are both rotatably installed inside an air guide ring cover (601), and the bottom of the base plate (202) is also connected to an exhaust pipe (204).

2. The anti-deflection device of an ion implanter according to claim 1, characterized in that: The three groups of isolation members (203) each comprise an upper shell (2031) and a lower shell (2032), and opposite sides of the upper shell (2031) and the lower shell (2032) are provided with a first piston chamber (2033) and a second piston chamber (2034) for use in conjunction with each other, and a semicircular hole (2035) is provided between the first piston chamber (2033) and the second piston chamber (2034); The top of the upper shell (2031) is fixedly connected to the bottom of the heat conducting plate (201), the bottom of the lower shell (2032) is fixedly connected to the top of the base plate (202), and the upper shell (2031) and the lower shell (2032) are fixed by welding.

3. The anti-deflection device of an ion implanter according to claim 2, characterized in that: The three silicon wafer positioning assemblies (4) each comprise a piston plate (401) and a negative pressure tube (402); a push rod (403) is fixedly connected to one side of the piston plate (401); one end of the push rod (403) is fixedly connected to a socket (404); a clamping rod (405) is fixedly connected to the top of the socket (404); The piston plate (401) is slidably mounted inside the two first piston chambers (2033); a first spring (407) is provided between the other side of the piston plate (401) and one side of the inner cavity of the first piston chamber (2033); the push rod (403) is slidably mounted between the two semicircular holes (2035); and the socket (404) is slidably mounted between the two second piston chambers (2034); The top of the heat conducting plate (201) is provided with three grooves (205), the bottom of the groove (205) is provided with a movable opening (206) connected with the second piston chamber (2034), the top of the socket (404) passes through the movable opening (206) and extends to the inside of the groove (205), the top of the outer periphery of the socket (404) is fixedly connected with a sealing plate (406), and the sealing plate (406) is in sliding contact with the inner surface of the groove (205).

4. The anti-deflection device of an ion implanter according to claim 3, characterized in that: One end of each of the three negative pressure tubes (402) is connected to the first piston chamber (2033), and the other end of the negative pressure tube (402) passes through the bottom plate (202) and is connected to the exhaust pipe (204), wherein the angle between the axis of the negative pressure tube (402) and the axis of the exhaust pipe (204) is 35°-45°.

5. The anti-deflection device of an ion implanter according to claim 4, characterized in that: The silicon wafer support assembly (5) comprises a support plate (501), the bottom of the support plate (501) is fixedly connected to a support rod (502), the bottom end of the support rod (502) is fixedly connected to a diverter piston block (503), the outer periphery of the diverter piston block (503) is evenly spaced and provided with three groups of first slide grooves (504) and three groups of second slide grooves (505), and the first slide grooves (504) and the second slide grooves (505) are alternately arranged; The top of the heat conducting plate (201) is provided with an embedding groove (207), the embedding groove (207) is communicated with the three grooves (205) respectively, and the embedding groove (207) is used in conjunction with the support plate (501), and the bottom end of the support rod (502) passes through the heat conducting plate (201) and extends to the inside of the exhaust pipe (204); The diverter piston block (503) is slidably installed inside the exhaust pipe (204), and three groups of guide slides (506) and three groups of temporary blocking plates (507) are evenly fixedly installed on the inner wall of the exhaust pipe (204). The guide slides (506) and the temporary blocking plates (507) are alternately arranged, and the guide slides (506) are slidably matched with the first slide groove (504), and the temporary blocking plates (507) are slidably matched with the second slide groove (505).

6. The anti-deflection device of an ion implanter according to claim 5, characterized in that: The three groups of temporary blocking plates (507) are all arranged directly above the connection between the negative pressure tube (402) and the exhaust pipe (204); the bottom ends of the three groups of guide slides (506) are commonly fixedly connected to a three-sided bracket (508); the three-sided bracket (508) is arranged below the negative pressure tube (402); the bottom of the diverter piston block (503) is fixedly connected to an auxiliary rod (509); the bottom end of the auxiliary rod (509) passes through the three-sided bracket (508) and is fixedly connected to a limiting block (5010); the outer periphery of the auxiliary rod (509) is also sleeved with a second spring (5011); the two ends of the second spring (5011) are respectively in contact with the bottom of the diverter piston block (503) and the top of the three-sided bracket (508).

7. The anti-deflection device of an ion implanter according to claim 6, characterized in that: A limit protection member (7) is also provided between the heat conducting plate (201) and the bottom plate (202), and the limit protection member (7) comprises a rotating ring (701) and an adjusting gear (702). Three groups of inclined grooves (703) are evenly spaced on the outer periphery of the rotating ring (701), and pins (704) are slidably installed inside the three groups of inclined grooves (703). The bottom end of the pin (704) is fixedly connected to a limit plate (705), and one end of the limit plate (705) passes through the upper shell (2031) and the lower shell (2032), and extends to the inside of the first piston chamber (2033); A plurality of teeth (706) are fixedly installed at the bottom of the outer periphery of the rotating ring (701) and located between the open ends of the two inclined grooves (703); the plurality of teeth (706) mesh with the adjusting gear (702); the adjusting gear (702) is arranged between the heat conducting plate (201) and the bottom plate (202); a bottom connecting rod of the adjusting gear (702) penetrates the bottom plate (202) and is fixedly installed with a hexagon socket head (707); a fastening bolt (708) is threadedly installed at the bottom of the bottom plate (202) through a connecting plate; one end of the fastening bolt (708) contacts the outer periphery of the hexagon socket head (707).

8. The anti-deflection device of an ion implanter according to claim 1, characterized in that: The rotary drive member (3) comprises a servo motor (301), the output end of the servo motor (301) is fixedly connected to a driving gear (302) via a coupling, a driven gear (303) is sleeved and fixedly connected to the outer periphery of the exhaust pipe (204), and the driving gear (302) and the driven gear (303) are meshed and matched; The servo motor (301) is fixedly mounted on the process chamber mounting bracket (1), and the bottom end of the exhaust pipe (204) passes through the process chamber mounting bracket (1) and extends to the bottom of the process chamber mounting bracket (1).

9. The anti-deflection device of an ion implanter according to claim 1, characterized in that: The heat conducting plate (201) and the bottom plate (202) are each provided with a first sealing groove (208) on one side opposite to the other. The top and bottom of the inner cavity of the air guide ring cover (601) are each provided with a second sealing groove (604) connected to the two first sealing grooves (208). The interiors of the two second sealing grooves (604) are each fixedly connected with a first sealing gasket (605), and the first sealing gasket (605) is used in conjunction with the first sealing groove (208). A plurality of reinforcing rubber columns (606) are also fixedly installed on one side opposite to the two first sealing gaskets (605), and the reinforcing rubber columns (606) are arranged inside the air guide ring cover (601).

10. The anti-deflection device of an ion implanter according to claim 9, characterized in that: The outer peripheries of the top and bottom of the air guide ring cover (601) are fixedly mounted with reinforcement rings (607); the top of the heat conducting plate (201) and the bottom of the base plate (202) are fixedly mounted with outward-turned covers (209) by means of bolts; the opposite sides of the two outward-turned covers (209) are in contact with the opposite sides of the two reinforcement rings (607), respectively; and a second sealing gasket (608) is arranged between the reinforcement ring (607) and the outward-turned covers (209).

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