A diamond N-type laser doping method and device

Abstract

The present invention provides a method and device for N-type laser doping of diamond. The diamond substrate is placed in an environment with a certain low oxygen concentration, and the surface of the diamond substrate is subjected to micro-modification treatment by a first laser; the diamond substrate after micro-modification treatment is placed in a doping solution containing a certain concentration of doping elements; N-type laser doping is carried out by scanning with a second laser a certain number of times. The present invention first performs laser micro-modification, and then directly immerses the diamond in the doping solution for laser doping, which can increase the doping carrier concentration and thus form effective N-type doping.

Description

Technical Field

[0001] The present invention relates to the field of diamond doping, and particularly relates to a diamond N-type laser doping method and device. Background Art

[0002] Diamond is an ultra-wide bandgap semiconductor material with excellent physical properties, extremely high thermal conductivity, reaching 22 W·cm -1 ·K -1 , an ultra-wide bandgap width of 5.5 eV, high carrier mobility, an electron mobility of 3800 cm 2 / (V·s), a hole mobility of 4500 cm 2 / (V·s), and a breakdown field strength as high as 13 MV / cm. Its physical properties are superior to those of the third-generation semiconductor materials GaN and SiC, and it has broad application prospects in the field of power electronic devices.

[0003] Undoped pure diamond is an excellent insulator with a resistivity ρ > 1015 Ω·cm. Achieving p-type and n-type conductivity is a basic requirement for fabricating diamond semiconductor devices. Among them, the development of p-type diamond is relatively mature, and the mainstream doping element is boron, but there is a problem of a rapid decrease in hole mobility at high doping levels; the current mainstream doping element for N-type diamond is phosphorus, and there are also problems such as deep impurity energy levels and large ionization energies, as well as defects in the diamond crystal after doping resulting in relatively low carrier concentration and mobility, and the resistivity is difficult to meet the requirements of the device.

[0004] The doping of diamond mainly includes doping during growth by the high temperature and high pressure method (HTHP), doping during growth by the chemical vapor deposition method (CVD), and ion implantation. Currently, for the doping of diamond, especially N-type doping, the doping difficulty is relatively large; HTHP is mainly for N-type doping, but it is difficult to activate; CVD is mainly for P-type doping, and there is less research on N-type doping; the ion implantation method will cause lattice damage, and diamond has a graphitization damage threshold, and when annealing exceeds the threshold, the diamond lattice cannot be restored, easily leading to doping failure. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a diamond N-type laser doping method and device that can form effective N-type doping.

[0006] The technical solution adopted by the present invention to solve the above technical problem is: a diamond N-type laser doping method, including:

[0007] Placing a diamond substrate in an environment with a certain low oxygen concentration; performing micro-modification treatment on the surface of the diamond substrate using a first laser;

[0008] The diamond substrate after slight modification is placed in a doping solution containing a certain concentration of doping elements; and the N-type laser doping is performed by a second laser scanning action for a certain number of times.

[0009] According to the above method, the parameters of the first laser are: wavelength 150-360nm, pulse width 1-100ns, power density 2-7J / cm 2 .

[0010] According to the above method, the micro-modification treatment is completed by performing step-scanning processing on the surface of the diamond substrate by the first laser, with a step overlap rate of 10-60% and a scan overlap rate of 50-90%.

[0011] According to the above method, the environment with a certain low oxygen concentration is an inert gas sealed environment, which is obtained by evacuating the pretreatment main chamber and filling it with inert gas, and the diamond substrate is placed in the pretreatment chamber;

[0012] The pre-processing chamber is provided with a protective glass as a light-transmitting surface for the laser.

[0013] According to the above method, the parameters of the second laser are: wavelength 150-360nm, pulse width 1-100ns, laser power density 2-8J / cm 2 The laser is applied 10-200 times to make the carrier concentration of the diamond substrate 1E17atoms / cm 3 above.

[0014] According to the above method, the N-type laser doping is completed by the second laser acting on the surface of the diamond substrate for multiple consecutive times.

[0015] According to the above method, the doping solution is placed in a doping main cavity, the doping main cavity has a light-transmitting surface, the doping solution contacts the light-transmitting surface, and the second laser performs N-type laser doping on the diamond surface in the doping liquid through the light-transmitting surface.

[0016] The device for implementing the diamond N-type laser doping method comprises:

[0017] A laser unit, used for providing the first laser and the second laser;

[0018] A pre-treatment chamber unit, used to provide the sealed environment;

[0019] A doping solution environment control unit, comprising a doping main cavity; the doping main cavity is used to contain the doping solution and fix the diamond substrate;

[0020] A stage for placing the pretreatment cavity unit and the doping solution environment control unit;

[0021] A three-dimensional moving stage, fixed below the stage, for controlling the three-dimensional movement of the stage, such that the first laser performs micro-modification treatment on the surface of the diamond substrate, and the second laser focuses and scans on the surface of the diamond substrate after micro-modification treatment for N-type laser doping;

[0022] A control unit for separately controlling the laser unit, the pretreatment cavity unit, the doping solution environment control unit, and the three-dimensional moving stage.

[0023] According to the above device, the laser unit includes a laser, a shaping lens group, a field mask, and a focusing lens group that are connected in an optical path in sequence.

[0024] According to the above device, the doping solution environment control unit further includes a circulation pipeline; the circulation pipeline is connected end to end with the doping main cavity such that the doping solution circulates between the doping main cavity and the circulation pipeline. A replenishment module and a filtering device are further provided on the circulation pipeline. The replenishment module is used to supplement doping elements, and the filtering device is used to filter impurities generated during laser doping;

[0025] The doping main cavity is provided with a ventilation port and a liquid injection port, and a protective glass is covered on the doping main cavity; the circulation pipeline includes a main circulation pipeline. A circulation pump for promoting the circulation of the doping liquid, a concentration detector for obtaining the concentration of doping elements, and the filtering device are provided on the main circulation pipeline; the replenishment module is connected in parallel with the main circulation pipeline, and a valve is provided at the connection to the main circulation pipeline.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1. First, use a laser to perform micro-modification treatment on the surface of the diamond, and then directly perform laser doping on the diamond in an environment immersed in the doping solution, which can increase the doping carrier concentration and thus form effective N-type doping.

[0028] 2. When the present invention uses the first laser to perform micro-modification on the diamond, a method of single-spot scanning and controlling the overlap rate is adopted to form a uniform and specific micro-modification treatment. When using the second laser to dope the diamond, a method of continuous multiple laser actions is adopted, which can increase the doping carrier concentration and form effective N-type doping.

[0029] 3. The doping solution controls its concentration and separates impurities through closed-loop control, thereby ensuring the concentration of doping elements and quickly separating the impurities that block the laser during the doping process, and thus ensuring effective N-type doping. Description of the Drawings

[0030] Figure 1Schematic diagram of the device structure according to an embodiment of the present invention.

[0031] Figure 2 Schematic diagram of the structure of the pretreatment cavity unit.

[0032] Figure 3 Schematic diagram of the structure of the doping solution environment control unit.

[0033] Figure 4 Relationship diagram of carrier concentration and laser energy when acting 100 times.

[0034] Figure 5 For energy 7 J / cm 2 Relationship diagram of carrier concentration and number of action times.

[0035] In the figure: C - control unit, L1 - laser, L2 - shaping lens group, L3 - field mask, L4 - focusing lens group, L5 - spectral confocal rangefinder, S1 - pretreatment cavity unit, S2 - doping solution environment control unit, S3 - stage, S4 - three-dimensional moving stage;

[0036] A - N-type diffused diamond substrate, S11 - nitrogen source, S12 - pretreatment main cavity, S13 - protective glass, S14 - vacuum pump, S15 - pressure gauge;

[0037] A' - diamond substrate after micro-modification treatment, S201 - exhaust / blow port, S202 - doping main cavity, S203 - protective glass, S204 - acid injection port, S205 - circulating liquid outlet, S206 - circulating liquid inlet, S207 - acid discharge port, S208 - main circulation pipeline, S209 - microporous filtration device, S210 - concentration detector, S211 - acid solution supplement module, S212 - circulation pump. Specific embodiments

[0038] The present invention will be further described below in conjunction with specific examples and drawings.

[0039] The present invention provides a diamond N-type laser doping method, including the following steps:

[0040] Step 1: Place the diamond substrate in an environment with a certain low oxygen concentration, and perform micro-modification treatment on the surface of the diamond substrate using a first laser.

[0041] The parameters of the first laser are: wavelength 150 - 360 nm, pulse width 1 - 100 ns, power density 2 - 7 J / cm 2 . After the surface of the diamond substrate is micro-modified, it is easier to dope. The power density is 2 - 7 J / cm 2Within a certain range, increasing the power density of the first laser will improve the final doped carrier concentration to a certain extent. Further, after being shaped by the shaping device, the first laser is focused on the surface of the diamond substrate through a focusing lens, and the diamond is processed by step scanning. The step overlap rate is 10%-60%, and the scanning overlap rate is 50%-90%. Within this range, the increase in the overlap rate will affect the doping concentration and can improve the carrier concentration to a certain extent. Generally, after being shaped by the shaping device, a square light spot is formed, and the size of the light spot on the processing focal plane is 0.5×0.5mm - 2mm×2mm. In this embodiment, it is 2mm×2mm. The whole wafer is processed by step scanning. Under the same energy density, the light spot size only affects the processing time.

[0042] Among them, the environment with a certain low oxygen concentration means that the oxygen concentration is not higher than 20 ppm. Specifically, it can be an inert gas environment. In this embodiment, it is a nitrogen environment. For example, nitrogen can be purged onto the surface of the silicon wafer. Preferably, the inert gas environment is a sealed environment. First, place and fix the diamond substrate in the pretreatment main cavity; open the air extraction valve and perform air extraction on the sealed pretreatment main cavity; when the pressure gauge detects that the cavity pressure drops to a preset low pressure (0.5 Mpa in this embodiment), control the nitrogen valve to open and fill nitrogen into the pretreatment main cavity; fill nitrogen while extracting air. When the oxygen concentration detected at the air extraction end is lower than the preset low oxygen concentration (20 ppm in this embodiment), close the nitrogen and air extraction valves to form the sealed environment with a certain low oxygen concentration. A protective glass is provided on the pretreatment main cavity as the light-transmitting surface for the laser. Those skilled in the art can understand that although the description of the light-transmitting surface is used here, not the entire surface requires a protective glass, and the area of the protective glass can be sufficient for the laser scanning area to pass through.

[0043] Preferably, the surface of the diamond substrate is height-measured by a rangefinder to generate the height data of the first plane to be processed. The height of the pretreatment cavity is vertically adjusted according to the height data of the first plane to be processed to ensure that when processing, the first laser acts at the same height and is focused on the focal plane for process processing, and the pretreatment main cavity is moved to perform step scanning processing on the diamond.

[0044] Step 2: Place the diamond substrate after micro-modification treatment in a doping solution with a certain doping element concentration, and use the second laser to continuously act on the surface of the diamond in the solution for a certain number of times for N-type laser doping.

[0045] Preferably, the doping solution is placed in the doping main cavity, and the doping main cavity has a light-transmitting surface. The second laser performs N-type laser doping on the surface of the diamond in the liquid through the light-transmitting surface, where the doping solution contacts the light-transmitting surface.

[0046] Among them, the doping element is phosphorus, and the doping solution is phosphoric acid solution. Preferably, the concentration of the phosphoric acid solution is above 70%.

[0047] The parameters of the second laser are: wavelength 150 - 360 nm, pulse width 1 - 100 ns, and laser power density is 2 J / cm 2 - 8 J / cm 2 . The second laser first passes through a shaping mirror group to optimize the optical performance, then adjusts the spot size and shape through a field mask, and finally passes through a focusing lens, passes through the protective glass (i.e., the light-transmitting surface) and the phosphoric acid solution, and is focused to form a pattern corresponding to the mask, acting on a position on the surface of the diamond substrate in contact with the phosphoric acid solution. It acts continuously on the surface of the diamond substrate multiple times to complete the N-type laser doping at one position, and then focuses on another position on the surface of the diamond substrate and acts continuously multiple times to complete the N-type laser doping at this position. Repeat until the N-type laser doping at all positions is completed. Among them, generally according to actual needs, different pattern masks are used to focus and generate patterns with corresponding specific spot sizes and shapes, which act on the surface of the diamond substrate to achieve doping. In this embodiment, a square mask is used to form a 2 mm * 2 mm spot for doping testing.

[0048] Specifically, the diamond substrate after micro-modification treatment is taken out from the pretreatment main cavity and placed into the doping main cavity. Among them, a protective glass is set at the top of the doping main cavity as the light-transmitting surface, the doping solution fills the doping main cavity, and the second laser is focused on the surface of the diamond substrate after micro-modification treatment for N-type laser doping.

[0049] Preferably, the concentration of the doping solution is controlled in a closed loop. The specific closed-loop control is: circulating the doping solution using a circulation pipeline, and a replenishment module is set in the circulation pipeline to replenish the doping element. More preferably, the closed-loop control also includes separating impurities, that is, a filtering device is set on the circulation pipeline to filter the impurities generated during laser doping.

[0050] The impurities generated during the doping process are mainly the products of the high-temperature decomposition of concentrated phosphoric acid. After the decomposition occurs, solid substances will be generated, resulting in the laser being blocked and unable to normally enter the surface of the processed diamond material.

[0051] Specifically, concentrated phosphoric acid will gradually lose water when heated, generating different products:

[0052] At 213 °C, it loses some water and turns into pyrophosphoric acid, and pyrophosphoric acid crystallizes into a colorless glassy state:

[0053]

[0054] At 300 °C, it loses one molecule of water and becomes metaphosphoric acid, which crystallizes into a colorless glassy state:

[0055]

[0056] At 480 °C, the molecules will lose all water and form phosphorus pentoxide, which is a white solid:

[0057]

[0058] Therefore, in the present invention, a replenishment module and a filtering device are provided in the circulation pipeline. On the one hand, the doped elements are replenished, and on the other hand, the above-mentioned impurities can be filtered out.

[0059] In this embodiment, polytetrafluoroethylene (PTFE) is used as the material of the doping main cavity. In the empty doping main cavity, PTEE screws and shrapnel are used to fix the diamond after micro-modification treatment; then a phosphoric acid solution with a mass percentage of 85% is filled until the entire doping main cavity is full; the liquid circulation pump is turned on, and the liquid is increased through the acid injection port until there are no bubbles in the doping main cavity.

[0060] Measure the surface of the diamond substrate again to generate the height data of the second plane to be processed.

[0061] Vertically adjust the cavity height according to the height data of the second plane to be processed to ensure that during processing, the second laser acts at the same height and is focused on the focal plane for process processing, and the doping main cavity is moved to perform step-by-step continuous processing on the diamond.

[0062] See Table 1. In the above steps, in step 1, a sealed nitrogen environment is used, the laser wavelength is 248 nm, the pulse width is 20 nm, the spot size on the processing focal plane is 2 mm * 2 mm, and the power density is 5 J / cm 2 , or step 1 is not performed, and in step 2, the laser wavelength is 248 nm, the pulse width is 20 nm, the processing focal plane size is 2 mm * 2 mm, and the power density on the process surface is 6 - 8 J / cm 2 , and the doping test is performed with the laser acting 10 - 200 times. The carrier concentration of the diamond sample after the doping test is measured.

[0063] The test results are shown in Table 1.

[0064] Data table of experimental groups 1 - 12 in Table 1

[0065] Experimental group Power density (J / cm2) Number of applications (times) Carrier concentration (atoms / cm3) Whether pretreated 1 6 100 1.67E+16 √ 2 6.5 100 1.24E+18 √ 3 7 10 2.35E+13 √ 4 7 10 1.88E+13 × 5 7 50 8.17E+17 √ 6 7 50 5.79E+17 × 7 7 100 3.69E+18 √ 8 7 100 2.44E+18 × 9 7 150 6.28E+18 √ 10 7 200 7.39E+18 √ 11 7.5 100 7.47E+18 √ 12 8 100 9.48E+18 √

[0066] As Figure 4 shown, when the laser acts 100 times, the carrier concentration increases with the increase of laser energy, and when the power density is above 6.5 J / cm 2 above, it reaches 1.24E18 atoms / cm 3 above, forming effective doping.

[0067] As Figure 5 shown, at a power density of 7 J / cm 2 , the carrier concentration increases with the number of pulses. When the number of pulses is more than 50, the carrier concentration reaches 8.17E17 atoms / cm 3 or more, forming effective doping.

[0068] As shown in Table 1, under the same conditions, after laser pretreatment (i.e., micro-modification), the doped carrier concentration has a certain increase.

[0069] The present invention also provides an apparatus for implementing the diamond N-type laser doping method described above. As Figure 1 shown, it includes:

[0070] A laser unit, including a laser L1, a shaping lens group L2, a field mask L3, and a focusing lens group L4 arranged in sequence along the optical path. The laser emitted by the laser L1 is first shaped and optimized in optical performance by the shaping lens group L2, then the spot size is adjusted by the field mask L3, and finally passes through the focusing lens group L4. The first laser and the second laser can use the same laser L1, and the parameters of the laser L1 can be adjusted as needed. The laser unit is also provided with a spectral confocal rangefinder L5 for measuring the height data of the diamond substrate surface.

[0071] A pretreatment cavity unit S1 for providing the sealed environment; the specific structure is as Figure 2 shown, including a pretreatment main cavity S12. One end of the pretreatment main cavity S12 is connected to a nitrogen source S11, the other end is connected to a vacuum pump S14, and the pretreatment main cavity S12 is also provided with a pressure gauge S15 for detecting the air pressure and a sensor for detecting the oxygen concentration. In this embodiment, the top surface of the pretreatment main cavity S12 is provided with a transparent protective glass S13, and the first laser passes through the protective glass S13 and acts on the surface of the diamond substrate A after N-type diffusion.

[0072] The doping solution environment control unit S2 includes a doping main cavity S202 and a circulation pipeline; the doping main cavity S202 is used to hold the doping solution (i.e., phosphoric acid solution) and fix the diamond substrate A' after micro-modification treatment; the circulation pipeline is connected to the head and tail of the doping main cavity S202 so that the doping solution circulates between the doping main cavity S202 and the circulation pipeline. A replenishment module and a filtering device are also provided on the circulation pipeline. The replenishment module is used to supplement doping elements, and the filtering device is used to filter impurities generated during laser doping. In this embodiment, an exhaust / blowing port S201, an acid injection port S204, an acid discharge port S207, a circulating liquid inlet S206, and a circulating liquid outlet S205 are provided on the doping main cavity S202. Among them, the acid injection port S204 is preferably arranged at the top of the doping main cavity S202, and the acid discharge port S207 is preferably arranged at the bottom of the doping main cavity S202, which is convenient for acid injection and acid discharge. The two ends of the main circulation pipeline S208 are respectively connected to the circulating liquid inlet S206 and the circulating liquid outlet S205, so that the doping main cavity S202 and the main circulation pipeline S208 form a circulation. The circulation of the doping solution is controlled by a circulation pump S212 provided on the main circulation pipeline 208. A microporous filtering device S209 is also provided on the main circulation pipeline S208 as the filtering device, and an acid concentration detector S210 for detecting the concentration of the phosphoric acid solution. Similarly, a protective glass S203 is provided on the doping main cavity S202. The second laser passes through the protective glass S203 and the phosphoric acid solution, and is focused on the surface of the diamond substrate in contact with the phosphoric acid solution to perform N-type phosphorus element doping. The replenishment module is an acid solution replenishment module S211, which is connected in parallel in the main circulation pipeline S208, and valves are provided before and after the acid solution replenishment module S211.

[0073] Preferably, the exhaust / blowing port S201 is arranged at the top of the doping main cavity S202, and the circulating liquid inlet S206 and the circulating liquid outlet S205 are arranged at the lower part of the doping main cavity S202. It is convenient to remove bubbles and ensure the stability of the circulating liquid circulation, so that even during the circulation process, the doping solution is in a stable state, avoiding the decline of the laser doping effect caused by bubbles and liquid flow.

[0074] The stage S3 is used to place and fix the pretreatment cavity unit S1 and the doping solution environment control unit S2.

[0075] The three-dimensional moving stage S4 is fixed below the stage S3 and is used to control the three-dimensional movement of the stage S3, adjust the height of the diamond substrate surface to be in the same plane as the laser focal plane, and adjust the movement of the diamond substrate surface on the processing plane while cooperating with the laser unit to complete the micro-modification treatment of the surface of the diamond substrate by the first laser and the continuous action of the second laser focused on the surface of the diamond substrate after micro-modification treatment for N-type laser doping.

[0076] A control unit C, configured to receive the ranging data of the spectral confocal rangefinder L5 and control the operations and action coordination of the laser unit, the pretreatment cavity unit S1, the doping solution environment control unit S2, and the three-dimensional moving stage S4.

[0077] When using the device of the present invention, during the doping process, the concentration of the phosphoric acid solution is detected by the concentration detector S210. When the concentration is lower than 83%, the valve of the acid replenishment module S211 is opened, and the valve of the pipeline in the main circulation pipeline S208 that is parallel to the acid replenishment module S211 is closed. The acid replenishment module S211 is filled with phosphoric acid solution with a concentration of more than 95%, and the circulating liquid can be replenished with acid. When the detected concentration reaches 85%, the valve of the acid replenishment module is closed, and the valve of the pipeline in the main circulation pipeline S208 that is parallel to the acid replenishment module S211 is opened, and the acid circulates normally, so as to ensure the concentration of phosphorus elements during the doping process.

[0078] When the consumption of the phosphoric acid solution is too fast, resulting in too low a concentration, and the concentration of the acid replenishment module S211 is consumed and cannot replenish the circulating liquid with high-concentration acid, the system reminds to replace it; after the acid replacement is completed and the concentration of the circulating liquid meets the requirements, normal operation can be carried out.

[0079] By using this device, the acid can circulate normally and the disturbance is very small.

[0080] It should be understood that for those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A diamond N-type laser doping method, characterized in that: Comprising: Placing a diamond substrate in an environment with a certain low oxygen concentration; Performing micro-modification treatment on the surface of the diamond substrate using a first laser; Placing the diamond substrate after micro-modification treatment in a doping solution containing a certain doping element concentration; Performing N-type laser doping by scanning the surface of the diamond substrate with a second laser a certain number of times.

2. The diamond N-type laser doping method according to claim 1, characterized in that: The parameters of the first laser are: wavelength 150 - 360 nm, pulse width 1 - 100 ns, and power density 2 - 7 J / cm 2 .

3. The diamond N-type laser doping method according to claim 2, wherein: The micro-modification treatment is completed by the first laser performing step-by-step scanning processing on the surface of the diamond substrate, with a step overlap rate of 10 - 60% and a scanning overlap rate of 50 - 90%.

4. The diamond N-type laser doping method according to claim 1, characterized in that: The environment with a certain low oxygen concentration is an inert gas sealed environment, obtained by evacuating and filling inert gas into the pretreatment main cavity, and the diamond substrate is placed in the pretreatment cavity; Among them, the pretreatment cavity is provided with a protective glass as the light-transmitting surface for the laser.

5. The diamond N-type laser doping method according to claim 1, characterized in that: The parameters of the second laser are as follows: wavelength 150 - 360 nm, pulse width 1 - 100 ns, laser power density 2 - 8 J / cm 2 , the number of laser applications is 10 - 200 times, so that the carrier concentration of the diamond substrate is above 1E17 atoms / cm 3 .

6. The diamond N-type laser doping method according to claim 5, characterized in that: The N-type laser doping is completed by the second laser acting on the surface of the diamond substrate continuously for multiple times.

7. The diamond N-type laser doping method according to claim 5 or 6, characterized in that: The doping solution is placed in the doping main cavity, and the doping main cavity has a light-transmitting surface. The doping solution contacts the light-transmitting surface, and the second laser performs N-type laser doping on the surface of the diamond in the doping liquid through the light-transmitting surface.

8. An apparatus for implementing the diamond N-type laser doping method according to any one of claims 1 to 7, characterized in that: Including A laser unit for providing the first laser and the second laser; A pretreatment cavity unit for providing a sealed environment; A doping solution environment control unit including a doping main cavity; the doping main cavity is used to hold the doping solution and fix the diamond substrate; A stage for placing the pretreatment cavity unit and the doping solution environment control unit; A three-dimensional moving stage fixed below the stage, used to control the three-dimensional movement of the stage, so that the first laser performs micro-modification treatment on the surface of the diamond substrate, and the second laser focuses on the surface of the diamond substrate after micro-modification treatment for scanning to perform N-type laser doping; A control unit for respectively controlling the laser unit, the pretreatment cavity unit, the doping solution environment control unit, and the three-dimensional moving stage.

9. The device according to claim 8, characterized in that: The laser unit includes a laser, a shaping lens group, a field mask, and a focusing lens group connected in sequence in the optical path.

10. The device according to claim 8, characterized in that: The doping solution environment control unit further includes a circulation pipeline; the circulation pipeline is connected end to end with the doping main cavity so that the doping solution circulates between the doping main cavity and the circulation pipeline. A replenishment module and a filtering device are also provided on the circulation pipeline. The replenishment module is used to supplement doping elements, and the filtering device is used to filter impurities generated during laser doping; The doping main cavity is provided with a ventilation port and a liquid injection port, and a protective glass is covered on the doping main cavity as the light-incident surface; the circulation pipeline includes a main circulation pipeline, and a circulation pump for promoting the circulation of the doping liquid, a concentration detector for obtaining the doping element concentration, and the filtering device are provided on the main circulation pipeline; the replenishment module is connected in parallel with the main circulation pipeline, and a valve is provided at the connection point to the main circulation pipeline.

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