A device and method for regulating the deposition uniformity of CVD high purity tungsten plate

Abstract

This invention relates to a device for controlling the uniformity of CVD high-purity tungsten plate deposition, belonging to the field of chemical technology. It includes a sealed device body, inside which, from top to bottom, are sequentially installed a first gas distributor, a second gas distributor, and a third gas distributor. The device body above the first gas distributor is a mixing chamber, and the device body below the third gas distributor is a reaction chamber. A stirrer is installed inside the mixing chamber, and an air inlet is provided on the side wall of the mixing chamber. A substrate is installed at the bottom of the reaction chamber, and a heating device is installed below the substrate. An air outlet is provided on the outer wall of the reaction chamber. This invention also relates to a method for controlling the uniformity of CVD high-purity tungsten plate deposition, controlling the heating power of each silicon carbide heating unit and controlling the rotation speed of the continuously variable speed rotating mechanism to control the deposition uniformity. This invention achieves the effect of controlling the CVD high-purity tungsten plate deposition uniformity within 1.5%.

Description

Technical Field

[0001] This invention belongs to the field of chemical vapor deposition technology, specifically relating to a device and method for controlling the deposition uniformity of CVD high-purity tungsten substrates, which is suitable for high-precision deposition of large-size tungsten substrates (100-500mm) in fields such as electronic devices and aerospace. Background Technology

[0002] Existing improved technologies (such as CN115974156A) enhance purity by optimizing the heating module, but still cannot solve the uniformity problem of large-area substrates. Therefore, there is an urgent need to develop a deposition control scheme that combines high purity and high uniformity.

[0003] Chinese patent CN38707323A uses single-temperature zone heating, resulting in a temperature difference of up to 15°C between the edge and the center, leading to a thickness deviation of >3%. The gas distributor in US Patent US20190153245A is a static structure and cannot dynamically adjust the gas concentration distribution. Chemical vapor deposition (CVD) is a technique that uses high temperatures to induce a chemical reaction in gaseous substances, depositing a solid thin film onto a substrate surface. In the preparation of high-purity tungsten plates, deposition uniformity is one of the key factors affecting the quality of the tungsten plate.

[0004] Currently, existing CVD methods for preparing high-purity tungsten plates suffer from numerous problems leading to poor deposition uniformity. For example, while existing technologies (such as CN112111747A) improve gas distribution by optimizing the reactor structure, they fail to address the issue of dynamic temperature field control. The uneven distribution of reactant gases within the reaction chamber results in varying tungsten deposition rates at different locations. This uneven temperature distribution also affects the rate and extent of the chemical reaction, further contributing to inconsistent deposition thickness. Furthermore, differences in the microstructure of the substrate surface and turbulent gas flow negatively impact deposition uniformity, thus significantly affecting production costs.

[0005] These uneven deposition issues lead to fluctuations in the physical and chemical properties of high-purity tungsten plates, such as inconsistent hardness, conductivity, and corrosion resistance, severely impacting their application in high-end fields like electronic devices and aerospace. Therefore, developing a device and method to effectively control the deposition uniformity of high-purity tungsten plates prepared by CVD is of significant practical importance. Summary of the Invention

[0006] To address the problem of uneven deposition in high-purity tungsten plates prepared by CVD in existing technologies and to improve the deposition quality of tungsten plates, this invention provides an apparatus and method for controlling the deposition uniformity of high-purity tungsten plates prepared by CVD, achieving the effect of controlling the deposition uniformity of high-purity tungsten plates by CVD to within 1.5%.

[0007] The present invention adopts the following technical solution: An apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition includes a sealed apparatus body. Inside the apparatus body, from top to bottom, are a first gas distributor, a second gas distributor, and a third gas distributor. The apparatus body above the first gas distributor is a mixing chamber, and the apparatus body below the third gas distributor is a reaction chamber. A stirrer is installed inside the mixing chamber, and an air inlet is provided on the side wall of the mixing chamber. A substrate is installed at the bottom of the reaction chamber, and a heating device is installed below the substrate. An air outlet is provided on the outer wall of the reaction chamber.

[0008] Preferably, the heating device includes a heater element, and a temperature sensor is provided on the heater element. The temperature sensor is connected to a controller that controls the heating of the heater element. The bottom of the substrate is also provided with a stepless speed-regulating rotation mechanism to control the rotation of the substrate.

[0009] Preferably, the heater element consists of multiple independently temperature-controlled silicon carbide heating units, each of which corresponds to a controller, and each controller corresponds to a temperature sensor. The silicon carbide heating units are radially divided into 5 to 8 annular control zones within the projection surface of the substrate. The power density of the silicon carbide heating units in each zone is set independently, with the power density set in the edge region being 10% to 30% higher than that in the center region. The temperature control accuracy of each zone is ±1℃.

[0010] Preferably, the agitator includes an impeller disposed inside the mixing chamber and a bearing connected to the impeller, wherein the bearing is externally connected to a motor; There are multiple air inlets, and each air inlet is equipped with a flow meter; The device body is also equipped with a pressure gauge; There are at least two air outlets, which are symmetrically and evenly distributed on the sidewall of the reaction chamber. The device body also has a viewing window on its side wall for laser interferometer detection.

[0011] Preferably, the first, second, and third gas distributors are all provided with holes, and the opening of the holes can be adjusted. The first-layer gas distributor has 46-56 holes, each with a diameter of φ7-9mm; The second-layer gas distributor has 60-80 holes, each with a diameter of φ4-6mm; The third-layer gas distributor has 158-178 holes, each with a diameter of φ1-3mm; The total flow area of ​​the first gas distributor A1: the total flow area of ​​the second gas distributor A2: the total flow area of ​​the third gas distributor A3 = 1:0.6:0.3.

[0012] A method for controlling the uniformity of CVD high-purity tungsten plate deposition includes the following steps: S1, calculating the required gas flow rate of various inlet deposition gases based on the deposition thickness of the substrate, selecting the number and diameter of holes in the first gas distributor, the second gas distributor, and the third gas distributor, and calculating the preheating temperature of the inlet gas pipe and the heating temperature of each silicon carbide heating unit. S2. Pre-treatment of the substrate; S3. Place the pretreated substrate above the heating device, install the selected first-layer gas distributor, second-layer gas distributor, and third-layer gas distributor on the device for regulating the uniformity of CVD high-purity tungsten plate deposition, and install a stirrer. S4. Preheat the air inlet pipe, control the opening of the hole, and simultaneously control the heating of each silicon carbide heating unit. Turn on the stirrer and the stepless speed regulating rotation mechanism. Heat the air inlet pipe and each silicon carbide heating unit to the preheating temperature. Open the air inlet and outlet. Intake air according to the calculated intake flow rate of each deposition gas through the flow meter. After the intake is completed, mix in the mixing chamber, and then pass through the holes on the first gas distributor, the second gas distributor and the third gas distributor in sequence. Finally, deposit it on the substrate in the reaction chamber. During the deposition process, the deposition thickness of the substrate is detected by a laser interferometer through an observation window. The deposition uniformity is controlled by adjusting the opening of the first, second, and third gas distributors, controlling the heating power of each silicon carbide heating unit, and controlling the rotation speed of the continuously variable rotating mechanism. S5. Post-processing is performed after deposition.

[0013] Preferably, the parameters in step S1 are calculated using the PINN framework of the PED Navier-Stokes equations of fluid dynamics and the law of conservation of mass. The pretreatment of the substrate in step S2 includes the following steps: etching with argon gas for 5-30 minutes under a pressure of 10-50 Pa and a power of 100-500 W to make the surface roughness Ra ≤ 0.1 μm; In 1×10⁻ 3 ~5×10⁻ 3 Under Pa, the temperature is increased to 800-1200℃ at a rate of 5-15℃ / min, held for 1-3 hours, and then slowly cooled to room temperature to eliminate vacuum stress.

[0014] Preferably, the inlet deposited gas in step S4 includes WF6 and H2, and the molar ratio of WF6 to H2 is 1:3-7; The preheating temperature of the air inlet pipe is controlled with a temperature accuracy of 40±10℃; the heating temperature of the silicon carbide heating unit is (100-300)℃±5℃. The silicon carbide heating unit is divided into 5 to 8 annular zones according to its radius, and the density of the silicon carbide heating unit increases by 10% to 15% with the increase of the radius; The opening size of the edge regions of the first, second, and third gas distributors is 1.3 to 1.8 times that of the central region. The detection cycle of the laser interferometer is 1-20 minutes.

[0015] Preferably, the method for controlling deposition uniformity in step S4 is as follows: When the laser interferometer detects a deposition thickness difference Δd ≥ 1%, the opening of the corresponding area of ​​the third layer is simultaneously adjusted by ±5~10%. When the real-time temperature difference ΔT between each silicon carbide heating unit detected by the temperature sensor is greater than 2℃, the heating power of the silicon carbide heating unit in the low-temperature zone increases to 105%~120% of the reference value, while the heating power of the silicon carbide heating unit in the high-temperature zone decreases to 80%~95% of the reference value. The substrate is rotated at a constant speed of 1~3 rpm. When the difference in deposition rate between the edge and the center is ≥5%, the rotation speed is increased by 0.5~1 rpm.

[0016] Preferably, S5, the deposition end and post-processing includes the following steps: when the deposition reaches the predetermined time or thickness, stop the supply of reaction gas and turn off the heating system; continue to supply argon gas to purge the reaction chamber until the residual gas is less than 1%, then stop, remove the residual gas in the chamber, and after the reaction chamber cools to room temperature, open the door of the reaction chamber and take out the deposited high-purity tungsten plate.

[0017] Beneficial effects of this invention: 1. This invention improves deposition uniformity: By precisely controlling the flow rate and ratio of the reactive gases through a gas supply system, providing a uniform temperature field through a heating system, and utilizing the substrate rotation function, the distribution of reactive gases on the substrate surface and reaction conditions are effectively improved, thereby significantly enhancing the deposition uniformity of high-purity tungsten plates. Actual testing shows that the thickness uniformity deviation of high-purity tungsten plates prepared using the apparatus and method of this invention can be controlled within 1.5%, far superior to the control levels of existing technologies.

[0018] 2. This invention improves deposition quality and performance consistency: Due to the improved deposition uniformity, the physical and chemical properties of high-purity tungsten plates are more stable and consistent. The fluctuation range of properties such as hardness, conductivity, and corrosion resistance of tungsten plates is significantly reduced, meeting the stringent quality requirements of high-end applications.

[0019] 3. This invention reduces production costs: The apparatus and method of this invention can improve the deposition quality and production efficiency of tungsten plates, reduce the scrap rate caused by uneven deposition, and thus reduce production costs. Furthermore, by precisely controlling the gas flow rate and heating power, energy and raw material consumption can also be saved. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the device in Embodiment 1 of the present invention; Figure 2 This is a structural diagram of the three-layer air distribution plate of Embodiment 1 of the device of the present invention; Figure 3 This is a diagram showing the distribution of the heater elements of the present invention.

[0021] In the attached diagram, 1-device body, 2-motor, 3-bearing, 4-flow meter, 5-air inlet, 6-pressure gauge, 7-impeller, 8-first-layer gas distributor, 9-second-layer gas distributor, 10-third-layer gas distributor, 11-base plate, 12-heater element, 13-temperature sensor, 14-air outlet, 15-viewing window. Detailed Implementation

[0022] Device Example 1 like Figure 1-3 As shown, a device for controlling the uniformity of CVD high-purity tungsten plate deposition includes a sealed device body 1, on which a pressure gauge 6 is also installed; inside the device body 1, from top to bottom, there are a first gas distributor 8, a second gas distributor 9, and a third gas distributor 10. The device body above the first gas distributor 8 is a mixing chamber, and the device body below the third gas distributor 10 is a reaction chamber. A stirrer is installed inside the mixing chamber, and the stirrer includes an impeller 7 disposed inside the mixing chamber and a device connected to the impeller 7. The device body 1 is connected to a bearing 3, which is externally connected to a motor 2. Multiple air inlets 5 are provided on the sidewall of the mixing chamber, each equipped with a flow meter 4. A substrate 11 is located at the bottom of the reaction chamber, and a heating device is located at the lower part of the substrate 11. The heating device includes a heater element 12, on which a temperature sensor 13 is installed. The temperature sensor 13 is connected to a controller, which controls the heating element 12. A continuously variable speed rotation mechanism for controlling the rotation of the substrate 11 is also provided at the bottom of the substrate 11. At least two air outlets 14 are provided on the outer wall of the reaction chamber, symmetrically and evenly distributed on the sidewall of the reaction chamber. A viewing window 15 for laser interferometer detection is also provided on the sidewall of the device body 1.

[0023] The heater element 12 is composed of multiple independently temperature-controlled silicon carbide heating units, each independently temperature-controlled silicon carbide heating unit corresponds to a controller, and each controller corresponds to a temperature sensor 13. The power density of a silicon carbide heater from center to edge follows the function P(r) = 4.0 + 0.0015 * r (W / cm²) 2 The setting is as follows: r is the radius in millimeters; the area is divided into 5 independent annular temperature control zones based on the radius, using silicon carbide heaters, with the power density increasing sequentially from the center to the edge, set to 4.0 W / cm². 2 4.2 W / cm 2 4.4 W / cm 2 4.6 W / cm 2 4.8 W / cm 2 To compensate for heat loss, the temperature control accuracy of each zone is ±1℃; The orifice openings of the first-layer gas distributor 8, the second-layer gas distributor 9, and the third-layer gas distributor 10 are all adjustable, with the orifice opening in the edge region being 1.3 times that in the center region; The first-layer gas distributor 8 has 46 holes, each with a diameter of φ7mm; The second-layer gas distributor 9 has 60 holes, each with a diameter of φ4mm; The third-layer gas distributor 10 has 158 holes, each with a diameter of φ1mm; The total flow area A1 of the first layer gas distributor 8 is equal to the total flow area A2 of the second layer gas distributor 9 and the total flow area A3 of the third layer gas distributor 10, which is 1:0.6:0.3.

[0024] Device Example 2 The difference between this embodiment and device embodiment 1 is that it is divided into 6 independent annular temperature control zones according to the radius, and silicon carbide heaters are used. The temperature control accuracy of each zone is ±1℃. The orifice openings of the first-layer gas distributor 8, the second-layer gas distributor 9, and the third-layer gas distributor 10 are all adjustable, with the orifice opening in the edge region being 1.5 times that in the center region. The first-layer gas distributor 8 has 50 holes, each with a diameter of φ8mm; The second-layer gas distributor 9 has 70 holes, each with a diameter of φ5mm; The third-layer gas distributor 10 has 168 holes, each with a diameter of φ2mm. Device Example 3 The difference between this embodiment and device embodiment 1 is that the heating array is divided into 8 independent annular temperature-controlled zones according to radius, using silicon carbide heaters, and the power density of the central region is set to 3.8 W / cm². 2 The power density in the outermost region is set to 5.0 W / cm². 2 The power density of the middle partition increases non-linearly to precisely match the thermal field distribution of the cavity, and the temperature control accuracy of each partition is ±1℃. The orifice openings of the first-layer gas distributor 8, the second-layer gas distributor 9, and the third-layer gas distributor 10 are all adjustable, with the orifice opening in the edge region being 1.8 times that in the center region; The first-layer gas distributor 8 has 55 holes, each with a diameter of φ9mm; The second-layer gas distributor 9 has 80 holes, each with a diameter of φ6mm; The third-layer gas distributor 10 has 178 holes, each with a diameter of φ3mm.

[0025] Method Example 1 A method for controlling the uniformity of CVD high-purity tungsten plate deposition, using the apparatus of Embodiment 1, includes the following steps: S1, performing calculations using the PINN framework of PED Navier-Stokes equations and the law of conservation of mass embedded in the parameters; calculating the required gas flow rates of various gas inlets 5 based on the deposition thickness of the substrate 11; selecting the number and diameter of holes in the first gas distributor 8, the second gas distributor 9, and the third gas distributor 10; and calculating the preheating temperature of the gas inlet pipe of the gas inlet 5 and the heating temperature of each silicon carbide heating unit. S2. Pre-treatment of substrate 11; etching with argon gas for 5 min at a pressure of 10 Pa and a power of 100 W to achieve a surface roughness Ra = 0.01 μm; etching at 1 × 10⁻ 3 The temperature is increased to 800℃ at a rate of 5℃ / min, held for 1 hour, and then slowly cooled to room temperature to eliminate vacuum stress. S3. Place the pretreated substrate 11 above the heating device, install the selected first layer gas distributor 8, second layer gas distributor 9, and third layer gas distributor 10 on the device for regulating the deposition uniformity of CVD high-purity tungsten plate, and install a stirrer. S4. Preheat the air inlet pipe of inlet 5 to a temperature control accuracy of 40±10℃; control the opening of the control orifice and simultaneously control the heating of each silicon carbide heating unit to a heating temperature of 100℃±5℃; turn on the stirrer and the stepless speed regulating rotation mechanism, heat the air inlet pipe of inlet 5 and each silicon carbide heating unit to the preheating temperature, open inlet 5 and outlet 14, the deposition gas of inlet 5 includes WF6 and H2, the molar ratio of WF6 to H2 is WF6:H2=1:3; introduce gas through flow meter 4 according to the calculated inlet flow rate of each deposition gas, according to δedge=δcenter×[1.5−0.02×(r / R)]. Adjust the opening of the third layer (center opening 0.5mm, edge opening 0.74mm), mix the gas in the mixing chamber after the gas intake is complete, and then pass through the holes on the first gas distributor 8, the second gas distributor 9 and the third gas distributor 10 in sequence, and finally deposit it on the substrate 11 in the reaction chamber. During the deposition process, the deposition thickness of the substrate 11 is detected through an observation window using a laser interferometer. The detection cycle of the laser interferometer is 10 minutes. The deposition uniformity is controlled by adjusting the opening of the first layer gas distributor 8, the second layer gas distributor 9, and the third layer gas distributor 10, controlling the heating power of each silicon carbide heating unit, and controlling the rotation speed of the continuously variable speed rotating mechanism. The method for controlling the deposition uniformity is as follows: when the laser interferometer detects Δd ≥ 1%, the opening of the corresponding area of ​​the third layer is adjusted by ±5% simultaneously; when the real-time temperature difference ΔT of each silicon carbide heating unit detected by the temperature sensor 13 is > 2℃, the heating power of the silicon carbide heating unit in the low-temperature zone is increased to 105% of the reference value, and the heating power of the silicon carbide heating unit in the high-temperature zone is reduced to 80% of the reference value; the substrate rotates at a uniform speed of 1 rpm, and when the edge / center deposition rate difference is 5%, the rotation speed is increased by 0.5 rpm; the vibration frequency is 2 Hz, and Δd is 0.6%; S5. Post-treatment after deposition: When the deposition reaches the predetermined time or thickness, stop the flow of reaction gas and turn off the heating system; continue to flow argon gas to purge the reaction chamber until the residual gas is less than 1%, then stop to remove the residual gas in the chamber. After the reaction chamber cools to room temperature, open the door of the reaction chamber and take out the deposited high-purity tungsten plate.

[0026] The wall thickness of the high-purity tungsten plate was measured: the thickness was tested according to the standard specification of ASTM B760-07 for tungsten thick plates, thin plates and foils. Table 1 shows the test data of the deposited high-purity tungsten plate in this embodiment.

[0027] Table 1 Location Thickness (mm) deviation(%) center 4.00 benchmark r=100mm 4.02 +0.5 r=200mm 3.98 -0.5 r=300mm 3.97 -0.8 Method Example 2 A method for controlling the uniformity of CVD high-purity tungsten plate deposition, using the apparatus of embodiment 2, includes the following steps: S1, performing calculations using the PINN framework of PED Navier-Stokes equations and the law of conservation of mass embedded in the parameters; calculating the required gas flow rates of various gas inlets 5 based on the deposition thickness of the substrate 11; selecting the number and diameter of holes in the first gas distributor 8, the second gas distributor 9, and the third gas distributor 10; and calculating the preheating temperature of the gas inlet pipe of the gas inlet 5 and the heating temperature of each silicon carbide heating unit. S2. Pre-treatment of substrate 11: Etching with argon gas for 15 min at a pressure of 30 Pa and a power of 300 W to achieve a surface roughness Ra = 0.07 μm; [The text abruptly ends here, likely due to an incomplete sentence or missing information.] 3 Under Pa conditions, the temperature is increased to 1000℃ at a rate of 10℃ / min, held at that temperature for 2 hours, and then slowly cooled to room temperature to eliminate vacuum stress. S3. Place the pretreated substrate 11 above the heating device, install the selected first layer gas distributor 8, second layer gas distributor 9, and third layer gas distributor 10 on the device for regulating the deposition uniformity of CVD high-purity tungsten plate, and install a stirrer. S4. Preheat the air inlet pipe of inlet 5. The preheating temperature of the air inlet pipe of inlet 5 is 40±10℃ with a temperature control accuracy. Control the opening of the orifice and simultaneously control the heating of each silicon carbide heating unit. The heating temperature of the silicon carbide heating unit is 200℃±5℃. Turn on the stirrer and the stepless speed regulating rotation mechanism. Heat the air inlet pipe of inlet 5 and each silicon carbide heating unit to the preheating temperature. Open inlet 5 and outlet 14. The deposition gas of inlet 5 includes WF6 and H2, and the molar ratio of WF6 to H2 is WF6:H2=1:5. The gas is introduced through flow meter 4 according to the calculated inlet flow rate of each deposition gas. After the gas is introduced, it is mixed in the mixing chamber and then passed through the orifices on the first gas distributor 8, the second gas distributor 9 and the third gas distributor 10 in sequence, according to δedge=δcenter×[1.5−0.02×(r / R)]. Adjust the opening of the third layer (center opening 0.8 mm, edge opening 1.2 mm); finally, deposit it on the substrate 11 in the reaction chamber; During the deposition process, the deposition thickness of the substrate 11 is detected through an observation window using a laser interferometer. The detection cycle of the laser interferometer is 20 minutes. The deposition uniformity is controlled by adjusting the opening of the first layer gas distributor 8, the second layer gas distributor 9, and the third layer gas distributor 10, controlling the heating power of each silicon carbide heating unit, and controlling the rotation speed of the continuously variable speed rotating mechanism. The method for controlling the deposition uniformity is as follows: when the laser interferometer detects Δd≥1%, the opening of the corresponding area of ​​the third layer is adjusted by ±8% synchronously; when the real-time temperature difference ΔT of each silicon carbide heating unit detected by the temperature sensor 13 is >2℃, the heating power of the silicon carbide heating unit in the low-temperature zone is increased to 110% of the reference value, and the heating power of the silicon carbide heating unit in the high-temperature zone is reduced to 85% of the reference value; the substrate rotates at a uniform speed of 2 rpm, and when the edge / center deposition rate difference is ≥5%, the rotation speed is increased by 1 rpm; the vibration frequency is 5Hz, and Δd=0.9%. S5. Post-treatment after deposition: When the deposition reaches the predetermined time or thickness, stop the flow of reaction gas and turn off the heating system; continue to flow argon gas to purge the reaction chamber until the residual gas is less than 1%, then stop to remove the residual gas in the chamber. After the reaction chamber cools to room temperature, open the door of the reaction chamber and take out the deposited high-purity tungsten plate.

[0028] The wall thickness of the high-purity tungsten plate was measured: the thickness was tested according to the standard specification of ASTM B760-07 for tungsten thick plates, thin plates and foils. Table 2 shows the test data of the deposited high-purity tungsten plate in this embodiment.

[0029] Table 2 Location Thickness (mm) deviation(%) center 6.00 benchmark r=100mm 6.05 +0.8 r=200mm 6.02 +0.3 r=300mm 5.98 -0.3 r=400mm 5.96 -0.7 r=500mm 5.94 -1.0 Method Example 3 A method for controlling the uniformity of CVD high-purity tungsten plate deposition, using the apparatus of embodiment 3, includes the following steps: S1, performing calculations using the PINN framework of PED Navier-Stokes equations and the law of conservation of mass embedded in the parameters; calculating the required gas flow rates of various gas inlets 5 based on the deposition thickness of the substrate 11; selecting the number and diameter of holes in the first gas distributor 8, the second gas distributor 9, and the third gas distributor 10; and calculating the preheating temperature of the gas inlet pipe of the gas inlet 5 and the heating temperature of each silicon carbide heating unit. S2. Pre-treatment of substrate 11: Etching with argon gas for 30 min at a pressure of 50 Pa and a power of 500 W to achieve a surface roughness Ra = 0.1 μm; [Further details about etching are needed for accurate translation.] 3 Under Pa, the temperature is increased to 1200℃ at 15℃ / min, held for 3 hours and then slowly cooled to room temperature to eliminate vacuum stress. S3. Place the pretreated substrate 11 above the heating device, install the selected first layer gas distributor 8, second layer gas distributor 9, and third layer gas distributor 10 on the device for regulating the deposition uniformity of CVD high-purity tungsten plate, and install a stirrer. S4. Preheat the air inlet pipe of inlet 5. The preheating temperature of the air inlet pipe of inlet 5 is 40±10℃ with a temperature control accuracy. Control the opening of the orifice and simultaneously control the heating of each silicon carbide heating unit. The heating temperature of the silicon carbide heating unit is 300℃±5℃. Turn on the stirrer and the stepless speed regulating rotation mechanism. Heat the air inlet pipe of inlet 5 and each silicon carbide heating unit to the preheating temperature. Open inlet 5 and outlet 14. The deposition gas of inlet 5 includes WF6 and H2, and the molar ratio of WF6 to H2 is WF6:H2=1:7. The gas is introduced through flow meter 4 according to the calculated inlet flow rate of each deposition gas. After the gas is introduced, it is mixed in the mixing chamber and then passed through the orifices on the first gas distributor 8, the second gas distributor 9 and the third gas distributor 10 in sequence, according to δedge=δcenter×[1.5−0.02×(r / R)]. The opening of the third layer is adjusted (center opening 0.9 mm, edge opening 1.35 mm); finally, it is deposited on the substrate 11 in the reaction chamber; During the deposition process, the deposition thickness of the substrate 11 is detected through an observation window using a laser interferometer. The detection cycle of the laser interferometer is 1 minute. The deposition uniformity is controlled by adjusting the opening of the first layer gas distributor 8, the second layer gas distributor 9, and the third layer gas distributor 10, controlling the heating power of each silicon carbide heating unit, and controlling the rotation speed of the continuously variable speed rotating mechanism. The method for controlling the deposition uniformity is as follows: when the laser interferometer detects Δd ≥ 1%, the opening of the corresponding area of ​​the third layer is adjusted by ±10% simultaneously; when the real-time temperature difference ΔT of each silicon carbide heating unit detected by the temperature sensor 13 is > 2℃, the heating power of the silicon carbide heating unit in the low-temperature zone is increased to 120% of the reference value, and the heating power of the silicon carbide heating unit in the high-temperature zone is reduced to 95% of the reference value; the substrate rotates at a uniform speed of 3 rpm, and when the edge / center deposition rate difference is 10%, the rotation speed is increased by 1 rpm; the vibration frequency is 10 Hz, and Δd is 1.3%; S5. Post-treatment after deposition: When the deposition reaches the predetermined time or thickness, stop the flow of reaction gas and turn off the heating system; continue to flow argon gas to purge the reaction chamber until the residual gas is less than 1%, then stop to remove the residual gas in the chamber. After the reaction chamber cools to room temperature, open the door of the reaction chamber and take out the deposited high-purity tungsten plate.

[0030] The wall thickness of the high-purity tungsten plate was measured: the thickness was tested according to the standard specification of ASTM B760-07 for tungsten thick plates, thin plates and foils. Table 3 shows the test data of the deposited high-purity tungsten plate in this embodiment.

[0031] Table 3 Location Thickness (mm) deviation(%) center 9.00 benchmark r=100mm 9.12 +1.3 r=200mm 9.07 +0.8 r=300mm 9.01 -0.3 r=400mm 8.96 -0.4 r=500mm 8.91 -1.0 r=600mm 8.87 -1.4 The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition, characterized in that, The device includes a sealed device body (1), inside which a first gas distributor (8), a second gas distributor (9) and a third gas distributor (10) are installed from top to bottom. The device body (1) above the first gas distributor (8) is a mixing chamber, and the device body below the third gas distributor (10) is a reaction chamber. A stirrer is installed inside the mixing chamber, and an air inlet (5) is installed on the side wall of the mixing chamber. A substrate (11) is installed at the bottom of the reaction chamber, and a heating device is installed at the bottom of the substrate (11). An air outlet (14) is installed on the outer wall of the reaction chamber.

2. The apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 1, characterized in that, The heating device includes a heater element (12), on which a temperature sensor (13) is provided, and the temperature sensor (13) is connected to a controller that controls the heating of the heater element (12); The bottom of the substrate (11) is also provided with a stepless speed regulating rotation mechanism for controlling the rotation of the substrate (11).

3. The apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 2, characterized in that, The heater element (12) is composed of multiple independently temperature-controlled silicon carbide heating units. Each independently temperature-controlled silicon carbide heating unit corresponds to a controller, and each controller corresponds to a temperature sensor (13). The silicon carbide heating unit is radially divided into 5 to 8 annular control zones within the projection surface of the substrate. The power density of the silicon carbide heating unit in each zone is set independently. The power density set in the edge region is 10% to 30% higher than that in the center region. The temperature control accuracy of each zone is ±1℃.

4. The apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 1, characterized in that, The agitator includes an impeller (7) disposed inside the mixing chamber and a bearing (3) connected to the impeller (7), and the bearing (3) is externally connected to a motor (2). There are multiple air inlets (5), and each air inlet (5) is equipped with a flow meter (4). A pressure gauge (6) is also provided on the main body (1) of the device; There are at least two air outlets (14), which are symmetrically and evenly distributed on the side wall of the reaction chamber. The device body (1) is also provided with a viewing window (15) for laser interferometer detection on its side wall.

5. The apparatus for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 1, characterized in that, The first gas distributor (8), the second gas distributor (9), and the third gas distributor (10) are all provided with holes, and the opening of the holes can be adjusted. The first-layer gas distributor (8) has 46-56 holes, each with a diameter of φ7-9mm; The second-layer gas distributor (9) has 60-80 holes, each with a diameter of φ4-6mm; The third-layer gas distributor (10) has 158-178 holes, each with a diameter of φ1-3mm; The total flow area of ​​the first gas distributor (8) is A1: the total flow area of ​​the second gas distributor (9) is A2: the total flow area of ​​the third gas distributor (10) is A3 = 1:0.6:0.

3.

6. A method for controlling the deposition uniformity of high-purity tungsten plates in CVD, utilizing the apparatus for controlling the deposition uniformity of high-purity tungsten plates in CVD according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Calculate the required gas flow rate of various gas inlets (5) based on the deposition thickness of the substrate (11), select the number and diameter of holes of the first layer gas distributor (8), the second layer gas distributor (9), and the third layer gas distributor (10), and calculate the preheating temperature of the gas inlet (5) and the heating temperature of each silicon carbide heating unit. S2. Pre-treatment of substrate (11); S3. Place the pretreated substrate (11) above the heating device, install the selected first layer gas distributor (8), second layer gas distributor (9), and third layer gas distributor (10) on the device for regulating the uniformity of CVD high-purity tungsten plate deposition, and install a stirrer. S4. Preheat the air inlet (5) and air inlet pipe, control the opening of the hole, and control the heating of each silicon carbide heating unit at the same time. Turn on the stirrer and the stepless speed regulation rotation mechanism. Heat the air inlet (5) and air inlet pipe and each silicon carbide heating unit to the preheating temperature. Open the air inlet (5) and air outlet (14). Through the flow meter (4), the air is introduced according to the calculated air inlet flow rate of each deposition gas. After the air is introduced, it is mixed in the mixing chamber. Then it passes through the holes on the first layer gas distributor (8), the second layer gas distributor (9) and the third layer gas distributor (10) in sequence. Finally, it is deposited on the substrate (11) in the reaction chamber. During the deposition process, the deposition thickness of the substrate (11) is detected by a laser interferometer through the observation window. The deposition uniformity is controlled by adjusting the opening of the holes of the first layer gas distributor (8), the second layer gas distributor (9) and the third layer gas distributor (10), controlling the heating power of each silicon carbide heating unit and controlling the rotation speed of the stepless speed regulating rotating mechanism. S5. Post-processing is performed after deposition.

7. The method for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 6, characterized in that, The parameters in step S1 are calculated using the PINN framework of the PED Navier-Stokes equations of fluid dynamics and the law of conservation of mass. The pretreatment of the substrate (11) in step S2 includes the following steps: etching with argon gas for 5 to 30 minutes under a pressure of 10 to 50 Pa and a power of 100 to 500 W to make the surface roughness Ra ≤ 0.1 μm; In 1×10⁻ 3 ~5×10⁻ 3 Under Pa, the temperature is increased to 800-1200℃ at a rate of 5-15℃ / min, held for 1-3 hours, and then slowly cooled to room temperature to eliminate vacuum stress.

8. A method for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 6, characterized in that, In step S4, the gas deposited at the air inlet (5) includes WF6 and H2, with a molar ratio of WF6 to H2 of 1:3-7; The preheating temperature of the air inlet (5) air inlet pipe is 40±10℃ with a temperature control accuracy of 40±10℃; the heating temperature of the silicon carbide heating unit is (100-300)±5℃. The silicon carbide heating unit is divided into 5 to 8 annular zones according to its radius, and the density of the silicon carbide heating unit increases by 10% to 15% with the increase of the radius; The opening size of the edge regions of the first gas distributor (8), the second gas distributor (9), and the third gas distributor (10) is 1.3 to 1.8 times that of the central region; The detection cycle of the laser interferometer is 1-20 minutes.

9. A method for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 6, characterized in that, The method for controlling deposition uniformity in step S4 is as follows: When the laser interferometer detects a deposition thickness difference Δd ≥ 1%, the opening of the corresponding area of ​​the third layer is simultaneously adjusted by ±5~10%. When the real-time temperature difference ΔT of each silicon carbide heating unit detected by the temperature sensor (13) is greater than 2℃, the heating power of the silicon carbide heating unit in the low temperature zone is increased to 105%~120% of the reference value, and the heating power of the silicon carbide heating unit in the high temperature zone is reduced to 80%~95% of the reference value; The substrate is rotated at a constant speed of 1~3 rpm. When the difference in deposition rate between the edge and the center is ≥5%, the rotation speed is increased by 0.5~1 rpm.

10. A method for controlling the uniformity of CVD high-purity tungsten plate deposition according to claim 6, characterized in that, S5. The deposition process and post-processing include the following steps: When the deposition reaches the predetermined time or thickness, stop the flow of reaction gas and turn off the heating system; continue to flow argon gas to purge the reaction chamber until the residual gas is less than 1% remaining, then stop to remove the residual gas in the chamber. After the reaction chamber cools to room temperature, open the door of the reaction chamber and take out the deposited high-purity tungsten plate.

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