Low-temperature injection control system and low-temperature injection control method applied to ion implanter

Abstract

The invention discloses a low-temperature injection control system and a low-temperature injection control method applied to an ion implanter. A remote power distribution cabinet is connected with a cold source through a power cable; the cold source is connected with the valve box through a network cable and a gas conveying pipeline, and the valve box is connected with the pre-cooling cavity and the low-temperature target table through pipelines. The first low-temperature target disc is fixed in the pre-cooling cavity and is connected with the adsorption power supply through an output cable; the cooling ring and the second low-temperature target disc are fixed on the low-temperature target table; the cold source is connected with the first ADIO controller through a control cable, the valve box is connected with the second ADIO controller through a control cable, the adsorption power source is connected with the third ADIO controller through a control cable, and the three ADIO controllers are connected with the industrial personal computer through optical fibers. The ion implanter has the advantages of being compact in structure, high in stability, convenient and fast to operate and the like, the requirement of a special product implantation technology for ion directional and positioned implantation is met, and the requirement of the market for diversified technology requirements of the ion implanter is met.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor ion implantation, and in particular to a low-temperature implantation control system and a low-temperature implantation control method applied to an ion implanter. Background Art

[0002] Ion implantation is a very important technology in modern integrated circuit manufacturing. It uses an ion implanter to dope semiconductors, that is, to inject specific impurity atoms (dopant) into silicon semiconductor crystals in an ion-accelerated manner to change their conductive properties and eventually form a transistor structure. Semiconductor device manufacturing technology and processes are very complex, and ion implantation doping is a very critical process in the semiconductor device manufacturing process. Compared with conventional thermal doping processes, ion implantation doping processes have the advantages of high-precision dose uniformity and repeatability, as well as small lateral diffusion. It overcomes the limitations of conventional processes, improves the integration, speed, yield and life of circuits, and reduces costs and power consumption.

[0003] With the development of technology in the semiconductor field, chip design performance has been improved, and the demand for special design chips has increased. It is necessary to dope at specific locations in specific devices. Ion implantation can be divided into three types according to temperature: high-temperature implantation model, room temperature wafer, and low-temperature implantation model.

[0004] The normal temperature implantation model has no temperature control system and injects the beam directly into the wafer. Due to the relatively fast speed of the ion beam, the wafer will generate heat when it contacts the ions, causing the wafer temperature to increase. After the ions are implanted into the wafer, due to the presence of a certain temperature on the wafer, the ions can diffuse freely and be evenly distributed inside the wafer. The domestic technology for this implantation method is relatively mature.

[0005] The high temperature machine adds a heating system to the normal temperature machine, first heating the wafer to a certain temperature before ion implantation. The characteristics of this process are that the wafer temperature is high, the ions injected into the wafer are more active, the free diffusion ability is strong, and the ions are more evenly distributed inside the wafer. This implantation method has achieved domestic technology breakthroughs and is developing rapidly, which can meet the wafer implantation process.

[0006] The low temperature machine also adds a refrigeration system to the normal temperature machine, first cooling the wafer to a certain temperature before ion implantation. The characteristics of this process are that the wafer temperature is low, the activity of the ions injected into the wafer is low, and the free diffusion ability is poor, which can achieve the ion directional positioning implantation function. This control process is a blank part of the ion implantation machine process, and the current ion implantation machine cannot meet the market's diverse requirements for ion implantation processes. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a low-temperature implantation control system and a low-temperature implantation control method for an ion implanter, which is convenient for assembly and disassembly, has high stability and is conducive to improving the implantation efficiency of the machine, in view of the shortcomings of the prior art.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0009] A low-temperature implantation control system for an ion implanter comprises: a remote power distribution cabinet, a cold source, a valve box, a precooling cavity, a first low-temperature target disk, an adsorption power supply, a low-temperature target platform, a cooling ring, a second low-temperature target disk, a first ADIO controller, a second ADIO controller, a third ADIO controller and an industrial computer; the output port of the remote power distribution cabinet is connected to the cold source through a power cable; the cold source is connected to the valve box through a network cable and a gas delivery pipeline, and the valve box is respectively connected to the precooling cavity and the low-temperature target platform through an output pipeline; the first low-temperature target disk is fixed in the precooling cavity and connected to the adsorption power supply through an output cable; the cooling ring and the second low-temperature target disk are both fixed on the low-temperature target platform, and the second low-temperature target disk is located above the cooling ring; the cold source is connected to the first ADIO controller through a control cable, the valve box is connected to the second ADIO controller through a control cable, the adsorption power supply is connected to the third ADIO controller through a control cable, and the first ADIO controller, the second ADIO controller and the third ADIO controller are respectively connected to the communication port of the industrial computer through optical fibers.

[0010] As a further improvement of the present invention, the cold source includes a cabinet body, in which a gas buffer tank, a cold source distribution cabinet, and a compressor, a refrigeration unit, a control valve group, a control input port and a power supply input port connected to the cold source distribution cabinet are arranged; the gas buffer tank is connected to the refrigeration unit, the refrigeration unit cooperates with the compressor to generate cooling gas, and forms a gas loop with the output gas port and the return gas port; the output gas port and the return gas port are respectively connected to the valve box through gas delivery pipelines.

[0011] As a further improvement of the present invention, a first solenoid valve, a first safety valve, a first pressure transmitter and a first manual instrument valve are also provided in the cabinet: the first solenoid valve is used to control the on-off of the gas during the cold source cooling process, the first safety valve is used to protect the safety of the gas circuit, the first pressure transmitter is used to monitor the pipeline pressure in real time and control the pipeline pressure output in real time, and the first manual instrument valve is used to monitor the temperature changes in the gas cooling process in real time.

[0012] As a further improvement of the present invention, a cold source operating table and a manual operating screen are provided on the front panel of the cabinet, and one end of the cold source power distribution cabinet is arranged on the front panel of the cabinet.

[0013] As a further improvement of the present invention, the low-temperature target stage includes a target stage air inlet pipe, a target stage air outlet pipe, a first cooling ring cylinder, a first temperature sensor, a second cooling ring cylinder and an air floating shaft; the first temperature sensor is arranged in the second low-temperature target disk to perform closed-loop temperature control; the air floating shaft is fixed to the lower end of the low-temperature target stage, and is used to support the up and down movement of the low-temperature target stage, the target stage air inlet pipe and the target stage air outlet pipe pass through the air floating shaft, one end of the target stage air inlet pipe and the target stage air outlet pipe are connected to the cooling ring, and one end of the target stage air inlet pipe and the target stage air outlet pipe are connected to the valve box to realize the entry and exit of the low-temperature gas in and out of the cooling ring; the first cooling ring cylinder and the second cooling ring cylinder are located outside the cooling ring, and when the system is running, the first cooling ring cylinder and the second cooling ring cylinder drive the cooling ring to extend to wrap the second low-temperature target disk, and the low-temperature gas cools the second low-temperature target disk and the adsorbed wafer through the cooling ring.

[0014] As a further improvement of the present invention, a first in-position sensor and a second in-position sensor are provided on the cooling ring to detect the extension displacement of the first cooling ring cylinder and the second cooling ring cylinder.

[0015] As a further improvement of the present invention, the valve box is provided with a low-temperature stop valve, a low-temperature regulating valve, a cold air return pipe, a cold air output pipe, a cold air input port and a cold air output port, the cold air input port and the cold air output port are respectively connected to a cold source, and the cold air return pipe and the cold air output pipe are both connected to the pre-cooling cavity and the low-temperature target platform.

[0016] As a further improvement of the present invention, the valve box is also provided with a temperature sensor, a pressure transmitter, a heater, a vacuum gauge and a control valve group.

[0017] As a further improvement of the present invention, a wafer library transmission component is provided between the pre-cooling chamber and the low-temperature target table to realize wafer transfer; the wafer library transmission component includes a left wafer library, a right wafer library, a right manipulator, a transmission orientation table and a left manipulator, the left wafer library and the right wafer library are arranged outside the ion implanter, the right manipulator and the left manipulator are symmetrically arranged on both sides of the transmission orientation table, and correspond to the right wafer library and the left wafer library respectively.

[0018] As a general technical concept, the present invention also provides a low temperature implantation control method based on the above-mentioned low temperature implantation control system applied to an ion implanter, comprising the following steps:

[0019] The following steps are involved:

[0020] Step S1, the engineering machine starts cooling the cold source, and after cooling is completed, opens the valve box to distribute cooling gas;

[0021] Step S2, cooling the first low-temperature target plate in the pre-cooling chamber to a set temperature;

[0022] Step S3, cooling the second low-temperature target disk in the low-temperature target stage to a set temperature;

[0023] Step S4, controlling the temperature of the second low-temperature target disk at a set value by a temperature closed-loop control method, and then performing an ion implantation process;

[0024] Step S5, after the ion implantation is completed, the wafer is transferred back to the wafer library by a robot, and the implanted wafer is subjected to a temperature recovery treatment inside the wafer library. When the wafer temperature reaches room temperature, the entire implantation process is completed.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] The low temperature injection control system and low temperature injection control method applied to the ion implanter of the present invention are as follows: a remote power distribution cabinet is connected to a cold source, the cold source is connected to a valve box, the valve box is respectively connected to a precooling cavity and a low temperature target platform, a first low temperature target plate is fixed in the precooling cavity, and an adsorption power supply is connected, a cooling ring and a second low temperature target plate are both fixed on the low temperature target platform, the cold source, the valve box and the adsorption power supply are respectively connected to corresponding ADIO controllers, and the ADIO controller is connected to an industrial computer, thus forming the main structure of a compact low temperature injection control system, which is installed in parallel with a normal temperature machine system, operates independently, can be disassembled and assembled separately, and is easy to maintain. The wafer can be cooled in advance by the precooling cavity, the injection efficiency of the machine is improved, and the risk of scratching the back of the wafer caused by wafer expansion is reduced. The present invention realizes the cooling of the wafer to achieve the set temperature injection, fills the lack of technology in the ion implanter, and meets the market demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure principle of a low temperature injection control system in a specific embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of the component layout of the cold source in a specific embodiment of the present invention;

[0029] Figure 3 It is a schematic diagram of the front panel of the cold source in a specific embodiment of the present invention;

[0030] Figure 4 It is a schematic diagram of the rear panel of the cold source in a specific embodiment of the present invention;

[0031] Figure 5 It is a schematic diagram of the structural principle of the low-temperature target platform in a specific embodiment of the present invention;

[0032] Figure 6 It is a schematic diagram of the component layout of the valve box in a specific embodiment of the present invention;

[0033] Figure 7 A schematic diagram of wafer transmission in a specific embodiment of the present invention;

[0034] Figure 8 It is a flow chart of the low temperature injection system process in a specific embodiment of the present invention;

[0035] Legend: 1. Remote power distribution cabinet; 2. Cold source; 3. Valve box; 4. Precooling cavity; 5. First low-temperature target plate; 6. Adsorption power supply; 7. Low-temperature target platform; 8. Cooling ring; 9. Second low-temperature target plate; 10. First ADIO controller; 11. Second ADIO controller; 12. Third ADIO controller; 13. Industrial computer; 21. Cabinet; 101. Compressor; 102. First power input port; 103. First control input port; 104. First water vapor input port; 105, cold source distribution cabinet; 106, refrigeration unit; 107, output gas port; 108, return gas port; 109, first solenoid valve; 110, first safety valve; 111, first pressure transmitter; 112, first manual instrument valve; 113, second power input port; 114, second control input port; 115, second water and gas input port; 116, cold source operation table; 117, manual operation screen; 119, gas buffer tank; 201, target platform air inlet pipe; 202, Target platform air outlet pipe; 203, first cooling ring cylinder; 204, first temperature sensor; 205, first in-position sensor; 206, second in-position sensor; 207, second cooling ring cylinder; 208, air floating shaft; 301, low temperature stop valve; 302, low temperature regulating valve; 303, second temperature sensor; 304, third temperature sensor; 305, second pressure transmitter; 306, third pressure transmitter; 307, first heater; 308, second heater; 309, second Safety valve; 310, vacuum gauge; 311, check valve; 312, second solenoid valve; 313, muffler; 314, second manual instrument valve; 315, first cold air output pipe; 316, first cold air return pipe; 317, second cold air output pipe; 318, second cold air return pipe; 319, cold air input port; 320, cold air output port; 401, left film library; 402, right film library; 403, right manipulator; 404, transmission orientation platform; 405, left manipulator. DETAILED DESCRIPTION

[0036] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0037] In the description of the present invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0039] Example

[0040] like Figure 1 As shown, the low-temperature implantation control system applied to the ion implanter of the present invention comprises: a remote power distribution cabinet 1, a cold source 2, a valve box 3, a precooling cavity 4, a first low-temperature target disk 5, an adsorption power supply 6, a low-temperature target platform 7, a cooling ring 8, a second low-temperature target disk 9, a first ADIO controller 10, a second ADIO controller 11, a third ADIO controller 12 and an industrial computer 13. The output port of the remote power distribution cabinet 1 is connected to the cold source 2 through a power cable. The cold source 2 is connected to the valve box 3 through a 10 Gigabit network cable and a gas delivery pipeline, and the valve box 3 is respectively connected to the precooling cavity 4 and the low-temperature target platform 7 through an output pipeline made of metal material. The first low-temperature target disk 5 is fixed in the precooling cavity 4 by screws, and is connected to the adsorption power supply 6 through an output cable. The cooling ring 8 and the second low-temperature target disk 9 are both fixed to the low-temperature target platform 7 by screws, and the second low-temperature target disk 9 is located above the cooling ring 8. The cold source 2 is connected to the first ADIO controller 10 through a control cable, the valve box 3 is connected to the second ADIO controller 11 through a control cable, the adsorption power supply 6 is connected to the third ADIO controller 12 through a control cable, and the first ADIO controller 10, the second ADIO controller 11 and the third ADIO controller 12 are respectively connected to the communication port of the industrial computer 13 through optical fibers. In the installation system of the industrial computer 13, the bottom layer of the software is configured with 0℃~1000℃ temperature setting and temperature collection, and the optical fiber communication is a dual loop, which is divided into the main loop communication and the auxiliary loop communication to prevent the abnormality of one optical fiber communication from affecting the normal operation of the system.

[0041] In this embodiment, the remote power distribution cabinet 1 is connected to the cold source 2 through a power cable. The input power supply parameters of the remote power distribution cabinet 1 are three-phase five-wire, including three live wires, one neutral wire, and one ground wire. The input phase voltage is 120V AC, the input line voltage is 208V AC, the voltage accuracy is ±10%, and the output rated power is 45kva. As a factory power supply access point, the remote power distribution cabinet 1 is equipped with an emergency stop control button to control the input and output in real time to protect the safety of equipment and personnel; the remote power distribution cabinet 1 can also input power to the cold source 2 to make it work.

[0042] In this embodiment, the cold source 2 is used to output cooling nitrogen to the valve box 3 for use by the system, and the temperature can drop to -150°C. The first ADIO controller 10 can realize the remote control function to turn on and off the cold source 2, collect the error signal of the cold source 2, and collect the working status signal of the cold source 2.

[0043] In this embodiment, the second ADIO controller 11 can remotely control various valve island switches in the valve box 3 and collect valve island status signals. The valve box 3 controls the working temperature of the pre-cooling cavity 4 by controlling the flow rate of nitrogen, and controls the working temperature of the low-temperature target 7 by controlling the flow rate of nitrogen.

[0044] In this embodiment, the first low-temperature target plate 5 fixes the wafer by electrostatic adsorption. After the first low-temperature target plate 5 is cooled, the wafer is cooled by heat transfer close to the wafer. Furthermore, the adsorption power supply 6 adopts a six-phase power supply, and the first low-temperature target plate 5 is connected to the six-phase power supply through an output cable. The six-phase power supply has a total of six outputs, which divides the first low-temperature target plate 5 into six blocks, with AC output, frequency of 32HZ, and output voltage of 0~1000V, which is used to fix the wafer by electrostatic adsorption to achieve the wafer cooling effect, while ensuring that the wafer will not move during the cooling process. The remote start and shutdown control of the six-phase power supply can be realized through the third ADIO control 12, and the power supply usage status can be monitored in real time.

[0045] like Figure 2 , Figure 3 and Figure 4 As shown, the cold source 2 includes a cabinet 21, in which a gas buffer tank 119, a cold source distribution cabinet 105, and a compressor 101, a refrigeration unit 106, a control valve group, a control input port and a power supply input port connected to the cold source distribution cabinet 105 are arranged. The compressor 101 realizes the condensation and evaporation process by compressing the gas nitrogen to achieve the refrigeration effect and the set temperature. The cold source distribution cabinet 105 is used to control electrical devices, communicate with the first ADIO controller 10, and execute internal programs. The gas buffer tank 118 is connected to the refrigeration unit 106, and the refrigeration unit 106 cooperates with the compressor 101 to generate cooling gas, and forms a gas loop with the output gas port 107 and the return gas port 108; the output gas port 107 and the return gas port 108 are respectively connected to the valve box 3 through the gas delivery pipeline.

[0046] The control input port includes a first control input port 103 and a second control input port 114, which are used as communication control exchange ports. The power input port includes a first power input port 102 and a second power input port 113, which are used to achieve the required power input. The cabinet 21 is also provided with a first water gas input port 104 and a second water gas input port 115, which are used as nitrogen cooling water input interfaces.

[0047] In this embodiment, the cabinet 21 is further provided with a first solenoid valve 109, a first safety valve 110, a first pressure transmitter 111 and a first manual instrument valve 112. The first solenoid valve 109 is used to control the on-off of the gas during the cooling process of the cold source 2, the first safety valve 110 is used to protect the safety of the gas circuit, the first pressure transmitter 111 is used to monitor the pipeline pressure in real time and control the pipeline pressure output in real time, and the first manual instrument valve 112 is used to monitor the temperature change of the gas cooling process in real time.

[0048] In this embodiment, a cold source operating table 116 and a manual operating screen 117 are provided on the front panel of the cabinet 21 , and one end of the cold source distribution cabinet 105 is provided on the front panel of the cabinet 21 .

[0049] like Figure 5 As shown, the low-temperature target stage 7 includes a target stage air inlet pipe 201, a target stage air outlet pipe 202, a first cooling ring cylinder 203, a first temperature sensor 204, a second cooling ring cylinder 207 and an air floating shaft 208. Three first temperature sensors 204 are provided in the second low-temperature target plate 9. The three first temperature sensors 204 monitor the temperature change in real time and realize the temperature control closed loop. When the monitored real-time temperature reaches the set temperature, nitrogen is fed in at a certain gas flow rate to maintain the current temperature ±1°C, and the machine starts to inject the ion beam. The air floating shaft 208 is fixed to the lower end of the low-temperature target stage 7 and is used to support the low-temperature target stage 7 to move up and down. The target stage air inlet pipe 201 and the target stage air outlet pipe 202 run through the air floating shaft 208. One end of the target stage air inlet pipe 201 and the target stage air outlet pipe 202 are connected to the cooling ring 8, and one end of the target stage air inlet pipe 201 and the target stage air outlet pipe 202 are connected to the valve box 3 to realize the low-temperature gas entering and exiting the cooling ring 8. The first cooling ring cylinder 203 and the second cooling ring cylinder 207 are located outside the cooling ring 8. When the system is running, the first cooling ring cylinder 203 and the second cooling ring cylinder 207 drive the cooling ring 8 to extend and wrap the second low-temperature target plate 9. The low-temperature gas cools the second low-temperature target plate 9 and the adsorbed wafer through the cooling ring 8. In this embodiment, the second low-temperature target plate 9 fixes the wafer by electrostatic adsorption, and the cooling ring 8 is driven by a double cylinder. Three output nitrogen holes are set on the cooling ring 8 to assist in reducing the temperature of the wafer.

[0050] In this embodiment, a first in-position sensor 205 and a second in-position sensor 206 are provided on the cooling ring 8 for detecting the extension displacement of the first cooling ring cylinder 203 and the second cooling ring cylinder 207, so as to achieve precise control of the displacement of the cooling ring 8 to avoid damage to the second low-temperature target plate 9 and the wafer.

[0051] like Figure 6 As shown, the valve box 3 is provided with a low-temperature stop valve 301, a low-temperature regulating valve 302, a cold air return pipe, a cold air output pipe, a cold air input port 319 and a cold air output port 320, the cold air input port 319 and the cold air output port 320 are respectively connected to the cold source 2, and the cold air return pipe and the cold air output pipe are both connected to the pre-cooling cavity 4 and the low-temperature target platform 7.

[0052] Specifically, the cold air return pipe includes a first cold air return pipe 316 and a second cold air return pipe 318, and the cold air output pipe includes a first cold air output pipe 315 and a second cold air output pipe 317. The first cold air output pipe 315 and the first cold air return pipe 316 are respectively connected to the pre-cooling cavity 4, and the second cold air output pipe 317 and the second cold air return pipe 318 are respectively connected to the low-temperature target platform 7.

[0053] In this embodiment, the valve box 3 is also provided with a temperature sensor, a pressure transmitter, a heater, a vacuum gauge 310 and a control valve group. The vacuum gauge 310 is used to detect the change of the vacuum degree in the valve box 3 in real time. Specifically, the temperature sensor includes a second temperature sensor 303 and a third temperature sensor 304, which are used to detect the temperature of the nitrogen entering the precooling cavity 4 and the low temperature target 7 respectively. The pressure transmitter includes a second pressure transmitter 305 and a third pressure transmitter 306, which are used to monitor the pressure of the pipelines connected to the precooling cavity 4 and the low temperature target 7 in real time and control the pipeline pressure output in real time. The heater includes a first heater 307 and a second heater 308, which can be used to heat the gas temperature entering the precooling cavity 4 and the low temperature target 7 according to actual process requirements. The control valve group includes a second safety valve 309, a check valve 311, a second solenoid valve 312, a muffler 313 and a second manual instrument valve 314. The second safety valve 309 is used to protect the safety of the gas circuit, the check valve 311 is used to prevent gas backflow, the second solenoid valve 312 is used to control the on-off of gas during the cooling process of the valve box 3, and the second manual instrument valve 314 is used to monitor the temperature change of the gas cooling process in real time.

[0054] In the secondary cooling process of the cooling system, when the temperature of the cold source 2 is lower than the set value, the pipeline and the valve box 3 are opened for cooling. The valve box 3 controls the gas output through the solenoid valve island and distributes two outputs. One gas is sent to the pre-cooling cavity 4 to initially cool the first low-temperature target plate 5 and the wafer adsorbed thereon. The initial cooling effects include: reducing the thermal expansion and contraction coefficient of the wafer; reducing the chance of wear on the back of the wafer, and reducing the number of particle contamination on the finished wafer; the initial cooling treatment can reduce the cooling time of the wafer on the target table and improve the working efficiency of the machine; the other gas is sent to the low-temperature target table 7 to cool the second low-temperature target plate 9 and the wafer adsorbed thereon.

[0055] In this embodiment, after the system is installed, the power supply circuit breaker of the remote power distribution cabinet 1 is closed, the power supply of the cold source 2 is normal, the industrial computer 13 sets the start command and sends it to the cold source 2 through the first ADIO controller 10, the cooling process of the cold source 2 starts, and the real-time temperature of the cold source 2 is monitored at the same time. When the monitored temperature reaches the set temperature, the cooling of the cold source 2 is completed, that is, the first-level cooling cycle is completed; the industrial computer 13 sets the control command and sends it to the valve box 3 through the second ADIO controller 11, the valve box 3 and the pipeline start internal circulation, and the cooling process begins. A temperature sensor is provided inside the valve box 3 to monitor the cooling process in real time. When the temperature reaches the set temperature, the second-level cooling is completed; wait for the wafer to be transferred to the pre-cooling chamber 4 The first low-temperature target plate 5 in the six-phase power output adsorbs the wafer, the valve box 3 starts to deliver air to the pre-cooling chamber 4, and starts preliminary cooling. When the temperature reaches 80% of the set value, the valve box 3 closes the gas supply, and the wafer is transported to the second low-temperature target plate 9 by the manipulator. After electrostatic adsorption, the position of the wafer on the second low-temperature target plate 9 is fixed, and the two cylinders of the cooling ring 8 are controlled to extend. The valve box 3 is opened to cool the second low-temperature target plate 9. A temperature sensor is installed inside the second low-temperature target plate 9 to monitor the cooling temperature in real time. When the monitored temperature reaches the set value, the valve box 3 controls and adjusts the gas supply to maintain the wafer at the set value, the cooling ring cylinder is retracted, and the wafer is ion implanted at a low temperature.

[0056] like Figure 7 As shown, a wafer library transmission component is provided between the precooling chamber 4 and the low temperature target stage 7 for realizing wafer transfer. The wafer library transmission component includes a left wafer library 401, a right wafer library 402, a right manipulator 403, a transmission orientation platform 404 and a left manipulator 405. The left wafer library 401 and the right wafer library 402 are arranged outside the ion implanter, and the right manipulator 403 and the left manipulator 405 are symmetrically arranged on both sides of the transmission orientation platform 404, and correspond to the right wafer library 402 and the left wafer library 401, respectively.

[0057] Furthermore, the film transfer process of the right film library 402 is as follows:

[0058] Step 1: The right robot 403 moves the wafer from the right wafer library 402 to the transmission orientation platform 404;

[0059] Step 2: The right robot 403 moves the wafer from the transfer orientation platform 404 to the pre-cooling chamber 4;

[0060] Step 3: The right robot 403 moves the wafer from the pre-cooling chamber 4 to the low-temperature target stage 7 for ion implantation;

[0061] Step 4: The left robot 405 takes the wafer out from the low-temperature target stage 7 and temporarily places the wafer in the left robot 405;

[0062] Step 5: After there is no wafer on the transfer orientation stage 404, place it on the transfer orientation stage 404;

[0063] Step 6: The right robot 403 moves the wafer from the transfer orientation platform 404 to the right wafer library 402;

[0064] The film transfer process of the left film library 401 is as follows:

[0065] Step 1: The left robot 405 moves the wafer from the left wafer library 401 to the transfer orientation platform 404;

[0066] Step 2: The right robot 403 moves the wafer from the transfer orientation platform 404 to the pre-cooling chamber 4;

[0067] Step 3: The right robot 403 moves the wafer from the pre-cooling chamber 4 to the low-temperature target stage 7;

[0068] Step 4: The left robot 405 moves the wafer from the low-temperature target stage 7 to the left wafer library 401;

[0069] In this embodiment, the low temperature implantation control method applied to the ion implanter, the control system working process is through remote operation, including the following steps:

[0070] Step S1, the engineering machine 13 turns on the cold source 2 for cooling, and after the cooling is completed, the valve box 3 is opened to distribute the cooling gas;

[0071] Step S2, cooling the first low-temperature target plate 5 in the pre-cooling cavity 4 to a set temperature;

[0072] Step S3, cooling the second low-temperature target plate 9 in the low-temperature target stage 7 to a set temperature;

[0073] Step S4, controlling the temperature of the second low-temperature target plate 9 at a set value by a temperature closed-loop control method, and then performing an ion implantation process;

[0074] Step S5, after the ion implantation is completed, the wafer is transferred back to the wafer library by a robot, and the implanted wafer is subjected to a temperature recovery treatment inside the wafer library. When the wafer temperature reaches room temperature, the entire implantation process is completed.

[0075] like Figure 8 As shown in the figure, the cooling process of the wafer in the system is:

[0076] (1) Cooling down the interior of the cold source 2 to realize the primary circulation of the cold source 2 and the internal temperature circulation of the cold source 2;

[0077] (2) After the first-level circulation of the cold source 2 is completed, the valve box 3 and the pipeline second-level cooling circulation are opened, and the cooling function is established;

[0078] (3) After the wafer is transferred to the pre-cooling chamber 4, the valve box 3 is opened, and cooling nitrogen is introduced into the pre-cooling chamber 4 to cool the wafer. The temperature of the first low-temperature target plate 5 is reduced to 80% of the set temperature for ion implantation, and the temperature accuracy is controlled within 1°C;

[0079] (4) The wafer is transferred to the transmission orientation stage 404 for orientation, and the wafer injection angle is adjusted to control the beam flow to be accurately injected into the wafer;

[0080] (5) After the wafer is oriented, it is transferred to the low-temperature target stage 7 for cooling;

[0081] (6) After the wafer temperature reaches the set value, ion implantation of the wafer begins;

[0082] (7) After the wafer begins ion implantation, it is transferred back to the wafer storage room for wafer temperature recovery.

[0083] (8) After the wafer is warmed up, the entire low-temperature injection process is completed and the wafer is transferred back to the wafer box.

[0084] This embodiment solves the problem of low temperature implantation. When the wafer is implanted with ions at low temperature, the ion diffusion capacity is weak, which meets the requirements of special product implantation process for ion directional positioning implantation. The control system of this embodiment fills the blank part of the ion implantation process and meets the market's demand for diversified ion implantation process requirements.

[0085] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A low temperature implantation control system for an ion implanter, characterized in that: include: A remote power distribution cabinet (1), a cold source (2), a valve box (3), a precooling cavity (4), a first low-temperature target disk (5), an adsorption power source (6), a low-temperature target platform (7), a cooling ring (8), a second low-temperature target disk (9), a first ADIO controller (10), a second ADIO controller (11), a third ADIO controller (12) and an industrial computer (13); the output port of the remote power distribution cabinet (1) is connected to the cold source (2) via a power cable; the cold source (2) is connected to the valve box (3) via a network cable and a gas delivery pipeline, and the valve box (3) is respectively connected to the precooling cavity (4) and the low-temperature target platform (7) via an output pipeline; the first low-temperature target disk (5) is fixed in the precooling cavity The valve box (3) is connected to the second ADIO controller (11) through a control cable, and the adsorption power supply (6) is connected to the third ADIO controller (12) through a control cable. The first ADIO controller (10), the second ADIO controller (11) and the third ADIO controller (12) are respectively connected to the communication port of the industrial computer (13) through optical fibers.

2. The low temperature implantation control system for ion implantation apparatus according to claim 1, characterized in that: The cold source (2) comprises a cabinet (21), wherein a gas buffer tank (119), a cold source distribution cabinet (105), and a compressor (101), a refrigeration unit (106), a control valve group, a control input port, and a power supply input port connected to the cold source distribution cabinet (105) are arranged in the cabinet (21); the gas buffer tank (118) is connected to the refrigeration unit (106), the refrigeration unit (106) cooperates with the compressor (101) to generate cooling gas, and forms a gas loop with an output gas port (107) and a return gas port (108); the output gas port (107) and the return gas port (108) are respectively connected to the valve box (3) through a gas delivery pipeline.

3. The low temperature implantation control system for ion implantation apparatus according to claim 2, characterized in that: The cabinet (21) is further provided with a first solenoid valve (109), a first safety valve (110), a first pressure transmitter (111) and a first manual instrument valve (112); the first solenoid valve (109) is used to control the on-off of gas during the cooling process of the cold source (2); the first safety valve (110) is used to protect the safety of the gas circuit; the first pressure transmitter (111) is used to monitor the pipeline pressure in real time and control the pipeline pressure output in real time; and the first manual instrument valve (112) is used to monitor the temperature change of the gas during the cooling process in real time.

4. The low temperature implantation control system for ion implantation apparatus according to claim 3, characterized in that: A cold source operating table (116) and a manual operating screen (117) are provided on the front panel of the cabinet (21), and one end of the cold source power distribution cabinet (105) is arranged on the front panel of the cabinet (21).

5. The low temperature implantation control system for ion implantation apparatus according to claim 2, characterized in that: The low-temperature target platform (7) comprises a target platform air inlet pipe (201), a target platform air outlet pipe (202), a first cooling ring cylinder (203), a first temperature sensor (204), a second cooling ring cylinder (207) and an air floating shaft (208); the first temperature sensor (204) is arranged in the second low-temperature target plate (9) to perform closed-loop temperature control; the air floating shaft (208) is fixed to the lower end of the low-temperature target platform (7) and is used to support the low-temperature target platform (7) to move up and down; the target platform air inlet pipe (201) and the target platform air outlet pipe (202) pass through the air floating shaft (208); the target platform air inlet pipe (201) and the target platform air outlet pipe (202) are connected to the air floating shaft (208); 01) and one end of the target platform air outlet pipe (202) are connected to the cooling ring (8), and one end of the target platform air inlet pipe (201) and the target platform air outlet pipe (202) are connected to the valve box (3) to enable low-temperature gas to enter and exit the cooling ring (8); the first cooling ring cylinder (203) and the second cooling ring cylinder (207) are located outside the cooling ring (8), and when the system is running, the first cooling ring cylinder (203) and the second cooling ring cylinder (207) drive the cooling ring (8) to extend to wrap the second low-temperature target disk (9), and the low-temperature gas passes through the cooling ring (8) to cool the second low-temperature target disk (9) and the adsorbed wafer.

6. The low temperature implantation control system for ion implantation apparatus according to claim 5, characterized in that: The cooling ring (8) is provided with a first in-position sensor (205) and a second in-position sensor (206) for detecting the extension displacement of the first cooling ring cylinder (203) and the second cooling ring cylinder (207).

7. The low temperature implantation control system for ion implantation apparatus according to claim 5, characterized in that: The valve box (3) is provided with a low-temperature stop valve (301), a low-temperature regulating valve (302), a cold air return pipe, a cold air output pipe, a cold air input port (319) and a cold air output port (320); the cold air input port (319) and the cold air output port (320) are respectively connected to a cold source (2); and the cold air return pipe and the cold air output pipe are both connected to a pre-cooling cavity (4) and a low-temperature target platform (7).

8. The low temperature implantation control system for ion implantation apparatus according to claim 7, characterized in that: The valve box (3) is also provided with a temperature sensor, a pressure transmitter, a heater, a vacuum gauge (310) and a control valve group.

9. The low temperature implantation control system for an ion implanter according to any one of claims 1 to 8, characterized in that: A wafer library transmission component is provided between the precooling chamber (4) and the low-temperature target platform (7) for realizing wafer transmission; the wafer library transmission component comprises a left wafer library (401), a right wafer library (402), a right robot (403), a transmission orientation platform (404) and a left robot (405); the left wafer library (401) and the right wafer library (402) are arranged outside the ion implanter; the right robot (403) and the left robot (405) are symmetrically arranged on both sides of the transmission orientation platform (404), and correspond to the right wafer library (402) and the left wafer library (401) respectively.

10. A low temperature implantation control method for a low temperature implantation control system applied to an ion implanter based on any one of claims 1 to 9, characterized in that: The following steps are involved: Step S1, the engineering machine (13) turns on the cold source (2) for cooling, and after the cooling is completed, the valve box (3) is turned on to distribute the cooling gas; Step S2, cooling the first low-temperature target plate (5) in the pre-cooling cavity (4) to a set temperature; Step S3, cooling the second low-temperature target plate (9) in the low-temperature target stage (7) to a set temperature; Step S4, controlling the temperature of the second low-temperature target plate (9) at a set value by means of a temperature closed-loop control method, and then performing an ion implantation process; Step S5, after the ion implantation is completed, the wafer is transferred back to the wafer library by a robot, and the implanted wafer is subjected to a temperature recovery treatment inside the wafer library. When the wafer temperature reaches room temperature, the entire implantation process is completed.

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