Purification method and device for preparing semiconductor-grade metal precursor and silicon-based precursor

Abstract

The invention discloses a purification method and device for preparing a semiconductor-grade metal precursor and a silicon-based precursor. The device comprises a feeding pipe, a material guiding pipe and a pressurizing pipe, wherein the material guiding pipe and the pressurizing pipe are communicated with each other; a constant-pressure assembly is arranged at one end of the pressurizing pipe, the constant-pressure pipe is communicated with the rectifying tower, a self-locking valve is arranged at the bottom end of the pressurizing pipe, and the self-locking valve is communicated with the feeding assembly; in the invention, the pressure in the feeding pipe and the pressurizing pipe is pressurized by the pressurizing equipment connected with the external pipe fixedly connected with one section of the pressurizing pipe to be consistent with the pressure in the rectifying tower, and when the pressure in the rectifying tower and the pressure in the constant-pressure pipe are equal, the control valve arranged at one end of the feeding pipe is passively opened; the driving assembly feeds the raw materials in the feeding pipe into the rectifying tower under the same pressure, and the situation that the pressure in the rectifying tower is unbalanced and the purifying efficiency of the rectifying tower is reduced due to the fact that the materials are in a pressure shortage state is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of purification equipment, and in particular to a purification method and device for preparing semiconductor-grade metal precursors and silicon-based precursors. Background Art

[0002] Metal precursors and silicon-based precursors have important applications as CVD or ALD precursor materials in the chip manufacturing process. Metal-based precursors and silicon-based precursors can generate important semiconductor thin film materials through ALD technology, such as using tetrakis(ethylmethylamino)zirconium (TEMAZ) and an oxygen precursor to generate zirconium dioxide (ZrO2) film through ALD reaction, using bis(diethylamino)silane (BDEAS) and an oxygen precursor to generate silicon dioxide (SiO2) film through ALD reaction, etc. One of the important factors that determine the quality of film performance is the purity of the film-forming materials metal precursors and silicon-based precursors, that is, the purity of the metal precursors and silicon-based precursors described in the present invention. Usually, when the chemical purity is ≥99.5% and the metal impurity purity is ≥99.9999% (6N), the prepared film performance can meet the requirements of semiconductor chip manufacturing.

[0003] For example, the Chinese patent with publication number CN208218736U and titled "A high-purity diethylaminosilane preparation device" uses a three-step operation of synthesis, filtration, and intermittent distillation to finally prepare electronic-grade diethylaminosilane with a purity of 99.999%. Although the distillation parameters such as the tower internals and reflux ratio of the intermittent distillation are described in detail, the distillation device used is an intermittent distillation device. Compared with the continuous distillation method, the intermittent distillation method has the disadvantages of high energy consumption and low distillation efficiency. Although the "A continuous production device suitable for liquid-solid reaction" reported in the patent publication number CN210729483U mentions the distillation device of the transition metal amine complex and the final purity of the product reaches 99.9999% (6N), the distillation method and device are not described in detail;

[0004] The shortcoming of the prior art is that, since the pressure in the distillation tower is changed by means of pressurization to accelerate the purification effect of the raw materials, the feeding device cannot maintain stability with the pressure in the tower, resulting in a loss of pressure in the distillation tower during the continuous feeding process, causing the raw material purification to fail to achieve the expected effect. Summary of the invention

[0005] The object of the present invention is to provide a purification method for preparing semiconductor-grade metal precursors and silicon-based precursors, comprising the following steps: Step 1: pressure-maintaining test and leak detection test of the purification device; pressurizing the purification device with high-purity inert gas to an absolute pressure of 300-600 kPa, and then maintaining the pressure for 12-48 hours. After the pressure drop of the entire purification device is ≤1%, the entire purification device is subjected to helium leak detection by a helium detection method, and the leak rate is ≤2*10 -10 pa.m 3 / s indicates that the air tightness of the entire purification device meets the purification requirements of metal precursors and silicon-based precursors;

[0006] Step 2: gas replacement of the purification device: first use a vacuum pump to evacuate the entire purification device to an absolute pressure of ≤1Pa, then cut off the vacuum valve, open the inert gas charging valve to pressurize the purification device to an absolute pressure of 101-110kPa, repeat the above operation 3-30 times, and replace the atmosphere in the purification device with an inert gas atmosphere;

[0007] Step 3: Turn on the scraped film evaporator for heating and the tower top condenser for cooling; open the scraped film evaporator heat medium inlet and outlet pipe valves, pass the heat medium to heat the scraped film evaporator to 40-200℃; open the tower top condenser refrigerant inlet and outlet pipe valves, pass the refrigerant to cool the condenser to -30-40℃;

[0008] Step 4: Evacuate the purification device and control the pressure; start the vacuum pump to pump the pressure in the purification device to an absolute pressure of 0.01Pa to 60000Pa and wait for feeding;

[0009] Step 5: Feeding crude metal precursor or crude silicon-based precursor; open the feed pump 2 and the feed valve 2a, 2b, 2c or 2d, and use the feed pump to transport the crude metal precursor or crude silicon-based precursor in the raw material tank 1 to the distillation tower at a constant rate of 1 to 10 kg / h.

[0010] In the step 4, the purification device is evacuated to an absolute pressure of 0.01 to 60000 Pa, preferably 0.1 to 50000 Pa;

[0011] The helium detection method in step 1 can be one or a combination of vacuum helium mass spectrometry leak detection, positive pressure helium mass spectrometry leak detection, vacuum pressure helium mass spectrometry leak detection, back pressure helium mass spectrometry leak detection, and the leakage rate of the purification device is required to be ≤2*10 - 10 pa.m 3 / s, preferably the leakage rate is ≤2*10 -11 pa.m 3 / s;

[0012] The high-purity inert gas in step 1 and step 2 is one of high-purity nitrogen, high-purity argon, high-purity helium, high-purity neon, and high-purity xenon, preferably high-purity nitrogen or high-purity argon;

[0013] The silicon-based precursor may be any one of bis(diethylamino)silane, bis(tert-butylamino)silane, diisopropylaminosilane, and tris(dimethylamino)silane;

[0014] In the step 3, the heating temperature of the scraped film evaporator is 40 to 200°C, preferably 50 to 150°C, and the temperature of the top condenser is cooled to -30 to 40°C, preferably -20 to 30°C;

[0015] The continuous distillation feed rate in step 5 is 1-10 kg / h, preferably 3-7 kg / h;

[0016] In the step 5, the chemical purity of the crude metal precursor and the silicon-based precursor is ≥ 98.5%, and the purity of the metal impurities is between 99% and 99.9%; the feed port position can be selected from 2a, 2b, 2c or 2d according to the different types of the crude metal precursor and the crude silicon-based precursor;

[0017] The tower kettle reboiler is a scraped film evaporator, and the scraper inside the scraped film evaporator can be any one of a hinged scraper, a rolling film scraper, a centrifugal scraper, and a fixed scraper. The evaporation area of ​​the scraped film evaporator is 0.1 to 5 m2, preferably 0.5 to 3 m2;

[0018] The distillation tower can be any one of a plate tower, a structured packing tower, and a random packing tower; the distillation tower has a height of 0.5 to 6 m, preferably 1 to 4 m, and a diameter of DN25 to DN200, preferably DN40 to DN120;

[0019] Distillation purification: After the crude metal precursor or the crude silicon-based precursor enters the tower, the continuous distillation purification of the crude metal precursor or the crude silicon-based precursor is completed under the heating effect of the scraped film evaporator of the tower kettle reboiler, the condensation effect of the tower top condenser and the heat and mass transfer of the gas-liquid two phases in the tower. The distillation reflux ratio is controlled between 5 and 0.5. The semiconductor-grade metal precursor or silicon-based precursor product is collected in the collecting tank 8 or 9 or 10 or 11. The chemical purity of the product is ≥99.5%, the purity of the metal impurities can reach 99.999% to 99.99999% (5N to 7N), and the product yield can reach 79% to 92%. In the step 2, the vacuum absolute pressure is ≤1pa, more preferably ≤0.01pa, and the positive pressure is filled to an absolute pressure of 101 to 110kpa, more preferably an absolute pressure of 102 to 105kpa.

[0020] The object of the present invention is to provide a purification device for preparing semiconductor-grade metal precursors and silicon-based precursors, wherein the pressure in the feed pipe and the boost pipe is boosted to be consistent with the pressure in the distillation tower through a boosting device connected to an external pipe fixedly connected to a section of the boosting pipe. When the pressure in the distillation tower is equal to the pressure in the constant pressure pipe, the control valve arranged at one end of the feed pipe is passively opened, so that the driving component can feed the raw materials in the feed pipe into the distillation tower under the same pressure, thereby avoiding pressure imbalance in the distillation tower caused by the lack of pressure of the material, thereby reducing the purification efficiency of the distillation tower.

[0021] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a purification method and device for preparing semiconductor-grade metal precursors and silicon-based precursors, comprising a feed pipe and a feed guide pipe and a booster pipe connected thereto;

[0022] A constant pressure assembly is provided at one end of the boosting pipe, and the constant pressure pipe is connected to the distillation tower; a self-locking valve is provided at the bottom end of the boosting pipe, and the self-locking valve is connected to the feeding assembly;

[0023] The booster pipe keeps the pressure in the feed pipe and the pressure in the distillation tower constant through the constant pressure pipe. At the same time, the constant pressure pipe controls the opening and closing of the control valve at the connection between the feed pipe and the distillation tower. The drive assembly arranged at one end of the feed pipe guides the raw materials in the constant feed pipe into the distillation tower.

[0024] As a further description of the above technical solution:

[0025] The constant pressure tube includes a piston block 1, and the piston block 1 is arranged in the constant pressure tube, one end of the piston block is fixedly connected to a connecting shaft, and the other end of the piston block is fixedly connected to a directional rod; the end of the connecting shaft away from the piston block 1 is fixedly connected to a piston block 2, and the piston block 2 is arranged in the boosting tube; a stop block is provided at the connection between the constant pressure tube and the distillation tower, one end of the stop block is connected to a support rod, and the support rod is transmission-connected to the control valve.

[0026] As a further description of the above technical solution:

[0027] The self-locking valve includes a partition plate 1, a sleeve rod is fixedly connected to the top of the partition plate 1, a sleeve cap is sleeved on the top of the sleeve rod, a support spring is fixedly connected to the top of the sleeve cap, and a partition plate 2 is fixedly connected to the end of the support spring away from the sleeve cap, and the partition plate is fixed in the boost pipe.

[0028] As a further description of the above technical solution:

[0029] The control valve includes a bracket, and the bracket is fixed on the feeding pipe. A movable bar is symmetrically slidably connected in the bracket. A rack one is fixedly connected between two movable bars respectively. The two rack ones are meshed and connected with a linkage assembly. The linkage assembly includes a gear block, and the gear block is meshed with rack one. Rack two is meshed at the bottom end of the gear block. One end of the rack two is fixedly connected with a connecting rod, and the connecting rod is fixedly connected to the support rod.

[0030] As a further description of the above technical solution:

[0031] The driving assembly comprises a hydraulic pump, one end of the hydraulic pump is fixedly connected with a movable rod, one end of the movable rod is fixedly connected with a pushing block, and the pushing block is arranged in the feeding pipe.

[0032] The present invention provides a purification method and device for preparing semiconductor-grade metal precursors and silicon-based precursors, which have the following beneficial effects:

[0033] In the present invention, the pressure in the feed pipe and the boosting pipe is boosted by a boosting device connected to an external pipe fixedly connected to a section of the boosting pipe to make the pressure consistent with the pressure in the distillation tower. When the pressure in the distillation tower is equal to the pressure in the constant pressure pipe, the control valve arranged at one end of the feed pipe is passively opened, so that the driving component can feed the raw materials in the feed pipe into the distillation tower under the same pressure, thereby avoiding pressure imbalance in the distillation tower caused by the lack of pressure of the material, thereby reducing the purification efficiency of the distillation tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A diagram of the continuous distillation and purification method of metal precursors and silicon-based precursors proposed by the present invention;

[0035] Figure 2 This is a diagram of the intermittent distillation purification method of the metal precursor and the silicon-based precursor in the present invention;

[0036] Figure 3 It is a schematic structural diagram of a purification device for preparing semiconductor-grade metal precursors and silicon-based precursors in the present invention;

[0037] Figure 4 It is a structural schematic diagram of the constant pressure tube in the present invention;

[0038] Figure 5 For the present invention Figure 4 Schematic diagram of the local structure at A in the middle;

[0039] Figure 6 It is a structural schematic diagram of the feed pipe in the present invention;

[0040] Figure 7 For the present invention Figure 6 Schematic diagram of the local structure at B in the middle;

[0041] Figure 8 It is a structural schematic diagram of the self-locking valve in the present invention;

[0042] Fig. 9 It is a structural schematic diagram of the control valve in the present invention;

[0043] Fig.10 It is a schematic diagram of the structure of the bracket in the present invention;

[0044] Fig.11 It is a structural schematic diagram of the linkage assembly in the present invention.

[0045] Legend:

[0046] Figure 1-Figure 2 ; 1. Crude metal precursor and crude silicon-based precursor raw material storage tank; 2. Delivery pump; 3. Wiped film evaporator; 4. Tower column; 5. Top condenser; 7. Reflux diaphragm valve; 6. Production diaphragm valve; 8. Top collecting tank; 9. Top collecting tank; 10. Tower bottom collecting tank; 11. Tower bottom collecting tank; 13. Crude precursor raw material storage tank; 14. Delivery pump; 16. Distillation tower bottom tank; 17. Tower column; 18. Top condenser; 20. Reflux diaphragm valve; 19. Production diaphragm valve; 21. Top collecting tank; 22. Top collecting tank.

[0047] Figure 3-Figure 11 ;1. Feeding pipe;11. Pull rod;12. Valve plate;13. Discharge port;2. Pressure boosting pipe;3. Constant pressure pipe;31. Piston block 1;32. Directional rod;33. Connecting shaft;34. Piston block 2;4. Driving assembly;41. Hydraulic pump;42. Movable rod;43. Pushing block;5. Control valve;51. Bracket;52. Movable bar;53. Rack 1;54. Linkage assembly;541. Limiting frame; 542, baffle; 543, gear block; 544, rack 2; 545, connecting rod; 55, reset spring; 56, support rod; 57, stop block; 6, external pipe; 7, material guide pipe; 8, self-locking valve; 81, partition plate 1; 82, sleeve rod; 83, guide groove; 84, connecting groove; 85, sleeve cap; 86, limiting block; 87, support spring; 88, partition plate 2; 89, slot hole. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0049] Reference Figure 1-2A purification method and device for preparing semiconductor-grade metal precursors and silicon-based precursors, comprising the following steps: Step 1: pressure-maintaining test and leak detection test of the purification device; pressurize the purification device with high-purity inert gas to an absolute pressure of 300-600 kPa, maintain the pressure for 12-48 hours, and then perform helium leak detection on the entire purification device with a helium detection method, with a leak rate of ≤2*10 -10 pa.m 3 / s indicates that the air tightness of the entire purification device meets the purification requirements of metal precursors and silicon-based precursors;

[0050] Step 2: gas replacement of the purification device: first use a vacuum pump to evacuate the entire purification device to an absolute pressure of ≤1Pa, then cut off the vacuum valve, open the inert gas charging valve to pressurize the purification device to an absolute pressure of 101-110kPa, repeat the above operation 3-30 times, and replace the atmosphere in the purification device with an inert gas atmosphere;

[0051] Step 3: Turn on the scraped film evaporator for heating and the tower top condenser for cooling; open the scraped film evaporator heat medium inlet and outlet pipe valves, pass the heat medium to heat the scraped film evaporator to 40-200℃; open the tower top condenser refrigerant inlet and outlet pipe valves, pass the refrigerant to cool the condenser to -30-40℃;

[0052] Step 4: Evacuate the purification device and control the pressure; start the vacuum pump to pump the pressure in the purification device to an absolute pressure of 0.01Pa to 60000Pa and wait for feeding;

[0053] Step 5: Feeding crude metal precursor or crude silicon-based precursor; open the feed pump 2 and the feed valve 2a, 2b, 2c or 2d, and use the feed pump to transport the crude metal precursor or crude silicon-based precursor in the raw material tank 1 to the distillation tower at a constant rate of 1 to 10 kg / h.

[0054] In the step 4, the purification device is evacuated to an absolute pressure of 0.01 to 60000 Pa, preferably 0.1 to 50000 Pa;

[0055] The helium detection method in step 1 can be one or a combination of vacuum helium mass spectrometry leak detection, positive pressure helium mass spectrometry leak detection, vacuum pressure helium mass spectrometry leak detection, back pressure helium mass spectrometry leak detection, and the leakage rate of the purification device is required to be ≤2*10 - 10 pa.m 3 / s, preferably the leakage rate is ≤2*10 -11 pa.m 3 / s;

[0056] The high-purity inert gas in step 1 and step 2 is one of high-purity nitrogen, high-purity argon, high-purity helium, high-purity neon, and high-purity xenon, preferably high-purity nitrogen or high-purity argon;

[0057] The silicon-based precursor may be any one of bis(diethylamino)silane, bis(tert-butylamino)silane, diisopropylaminosilane, and tris(dimethylamino)silane;

[0058] In the step 3, the heating temperature of the scraped film evaporator is 40 to 200°C, preferably 50 to 150°C, and the temperature of the top condenser is cooled to -30 to 40°C, preferably -20 to 30°C;

[0059] The continuous distillation feed rate in step 5 is 1-10 kg / h, preferably 3-7 kg / h;

[0060] In the step 5, the chemical purity of the crude metal precursor and the silicon-based precursor is ≥ 98.5%, and the purity of the metal impurities is between 99% and 99.9%; the feed port position can be selected from 2a, 2b, 2c or 2d according to the different types of the crude metal precursor and the crude silicon-based precursor;

[0061] The tower kettle reboiler is a scraped film evaporator, and the scraper inside the scraped film evaporator can be any one of a hinged scraper, a rolling film scraper, a centrifugal scraper, and a fixed scraper. The evaporation area of ​​the scraped film evaporator is 0.1 to 5 m2, preferably 0.5 to 3 m2;

[0062] The distillation tower can be any one of a plate tower, a structured packing tower, and a random packing tower; the distillation tower has a height of 0.5 to 6 m, preferably 1 to 4 m, and a diameter of DN25 to DN200, preferably DN40 to DN120;

[0063] Distillation purification: After the crude metal precursor or the crude silicon-based precursor enters the tower, the continuous distillation purification of the crude metal precursor or the crude silicon-based precursor is completed under the heating effect of the scraped film reboiler in the tower kettle reboiler, the condensation effect of the tower top condenser and the heat and mass transfer of the gas-liquid two phases in the tower. The distillation reflux ratio is controlled between 5 and 0.5. The semiconductor-grade metal precursor or silicon-based precursor product is collected in the collection tank 8 or 9 or 10 or 11. The chemical purity of the product is ≥99.5%, the purity of the metal impurities can reach 99.999% to 99.99999% (5N to 7N), and the product yield can reach 79% to 92%. In the step 2, the absolute pressure of the vacuum is ≤1pa, more preferably ≤0.01pa, and the positive pressure is filled to an absolute pressure of 101 to 110kpa, more preferably an absolute pressure of 102 to 105kpa.

[0064] Example 1

[0065] The purification device was pressurized with high-purity argon gas to an absolute pressure of 300 kPa. After maintaining the pressure for 24 hours, the pressure drop of the device was 0.8%. The leak rate was 1*10-10 Pa.m after helium mass spectrometry was used to detect the leak.3 / s, the leakage rate is qualified, and then it is pressurized with high-purity argon to an absolute pressure of 102kPa, and then evacuated to an absolute pressure of 1pa with a vacuum pump. After repeating the above operation 30 times, the temperature of the wiped film evaporator is raised to 80°C, the temperature of the top condenser is reduced to 20°C, the vacuum pump is turned on to control the pressure in the purification device at an absolute pressure of 2900-3100Pa, and then the crude silicon-based precursor bis(diethylamino)silane [abbreviated as: BDEAS] in the raw material tank 1 is pumped from the feed port 2c position at a constant rate of 10kg / h to a distillation tower with a tower height of 6m and a tower diameter of DN200 for continuous distillation, and the reflux ratio is 0.5. The high-purity silicon-based precursor bis(diethylamino)silane [abbreviated as: BDEAS] in the top product collecting tank 8 has a chemical purity of 99.9% detected by nuclear magnetic resonance hydrogen spectrum, and a metal impurity purity of 99.99999% (7N) detected by I CP-MS, and the product yield is 90%.

[0066] Example 2

[0067] The purification device was pressurized with high-purity helium to an absolute pressure of 600 kPa and maintained for 48 hours. The pressure drop of the device was 0.5%. The positive pressure helium mass spectrometer was used to detect leaks, and the leak rate was 1*10-11 pa.m 3 / s, the leakage rate is qualified, and then it is pressurized with high-purity helium to an absolute pressure of 110kPa, and then evacuated to an absolute pressure of 0.01pa with a vacuum pump. After repeating the above operation 3 times, the temperature of the wiped film evaporator is raised to 90°C, the temperature of the top condenser is reduced to 30°C, the vacuum pump is turned on to control the pressure in the purification device at an absolute pressure of 0.1-1pa, and then the crude metal precursor tetrakis(ethylmethylamino)zirconium [abbreviated as: TEMAZ] in the raw material tank 1 is pumped from the feed port 2a position at a constant rate of 3kg / h to a distillation tower with a height of 2m and a diameter of DN25 for continuous distillation, the reflux ratio is 5, the high-purity metal precursor tetrakis(ethylmethylamino)zirconium [abbreviated as: TEMAZ] in the tower bottom product collecting tank 11 is detected by nuclear magnetic resonance hydrogen spectrum to have a chemical purity of 99.6%, the metal impurity purity is detected by ICP-MS to be 99.9999% (6N), and the product yield is 80%.

[0068] Example 3

[0069] The purification device was pressurized with high-purity nitrogen to an absolute pressure of 400 kPa and maintained for 12 hours. The pressure drop of the device was 0.8%. The vacuum pressure method helium mass spectrometer was used to detect leaks, and the leak rate was 1.5*10-11 pa.m 3 / s, the leakage rate is qualified, and then high-purity nitrogen is used to pressurize to an absolute pressure of 105kPa, and then a vacuum pump is used to evacuate to an absolute pressure of 0.5pa. After repeating the above operation 3 times, the temperature of the wiped film evaporator is raised to 70°C, and the temperature of the top condenser is reduced to 10°C. The vacuum pump is turned on to control the pressure in the purification device at an absolute pressure of 5900-6100Pa, and then the crude silicon-based precursor bis(tert-butylamino)silane [abbreviated as BTBAS] in the raw material tank 1 is pumped from the feed port 2b position at a constant rate of 5kg / h to a distillation tower with a tower height of 3m and a tower diameter of DN100 for continuous distillation. The reflux ratio is 1. The chemical purity of the high-purity silicon-based precursor bis(tert-butylamino)silane [abbreviated as BTBAS] in the top product collection tank 9 is 99.8% by nuclear magnetic resonance hydrogen spectrum detection, and the metal impurity purity is 99.9999% (6N) by ICP-MS detection, and the product yield is 89%

[0070] Reference Figure 3-11 , a purification method and device for preparing semiconductor-grade metal precursors and silicon-based precursors, comprising a feed pipe 1 and a guide pipe 7 and a booster pipe 2 connected thereto; a constant pressure assembly 3 is provided at one end of the booster pipe 2, and the constant pressure pipe is connected to a distillation tower, a self-locking valve 8 is provided at the bottom of the booster pipe 2, and the self-locking valve 8 is connected to the feed assembly; the booster pipe 2 keeps the pressure in the feed pipe 1 and the pressure in the distillation tower constant through the constant pressure pipe, and at the same time, the constant pressure pipe controls the opening and closing of a control valve 5 at the connection between the feed pipe 1 and the distillation tower, and a driving assembly 4 arranged at one end of the feed pipe 1 guides the raw materials in the constant feed pipe 1 into the distillation tower;

[0071] Specifically, the feed pipe 1 is connected to the distillation tower, the booster pipe 2 and the guide pipe 7 respectively, and the guide pipe 7 is connected to the external feed equipment. When the distillation tower is set to a preset pressure, the pressure in the constant pipe compresses the space in the connected booster pipe 2, so that the raw materials in the feed pipe 1 connected to the booster pipe 2 and the pressure in the pipe are lower than the pressure in the constant pressure pipe. The booster equipment connected to the external pipe 6 fixedly connected to a section of the booster pipe 2 boosts the pressure in the feed pipe 1 and the booster pipe 2 to be consistent with the pressure in the distillation tower. When the pressure in the distillation tower is equal to that in the constant pressure pipe, the control valve 5 arranged at one end of the feed pipe 1 is passively opened, so that the drive component 4 can deliver the raw materials in the feed pipe 1 into the distillation tower at the same pressure, so as to avoid the pressure imbalance in the distillation tower caused by the lack of pressure of the material, thereby reducing the purification efficiency of the distillation tower.

[0072] The constant pressure tube includes a piston block 31, and the piston block 31 is arranged in the constant pressure tube, one end of the piston block 31 is fixedly connected to a connecting shaft 33, and the other end of the piston block 31 is fixedly connected to a directional rod 32; the end of the connecting shaft 33 away from the piston block 31 is fixedly connected to a piston block 2 34, and the piston block 2 34 is arranged in the boosting tube 2; a stop block 57 is provided at the connection between the constant pressure tube and the distillation tower, one end of the stop block 57 is connected to a support rod 56, and the support rod 56 is transmission-connected to the control valve 5;

[0073] Specifically, when the piston block 1 31 in the constant pressure pipe is connected to the distillation tower, the pressure in the tower causes the piston block 1 31 to drive the piston block 2 34 fixedly connected to the connecting shaft 33 to move in a directional manner along the boosting pipe 2. When the boosting pipe 2 increases the pressure through the boosting device connected to the external pipe 6, the piston block 2 34 in the boosting pipe 2 drives the piston block 1 31 to move in a directional manner, so that the piston block 1 31 drives the control valve 5 connected to the stop block 57 to open and close, so that the control valve 5 feeds the feed pipe 1 and the distillation tower at a constant pressure, thereby avoiding pressure imbalance in the distillation tower, which leads to a reduction in the efficiency of the raw material reaction in the distillation tower.

[0074] The self-locking valve 8 comprises a partition plate 1 81, a sleeve rod 82 is fixedly connected to the top of the partition plate 1 81, a sleeve cap 85 is sleeved on the top of the sleeve rod 82, a support spring 87 is fixedly connected to the top of the sleeve cap 85, and a partition plate 2 88 is fixedly connected to the end of the support spring 87 away from the sleeve cap 85, and the partition plate is fixed in the boost pipe 2;

[0075] Specifically, a guide groove 83 and a connecting groove 84 are provided in a sleeve rod 82 fixedly connected to the partition plate 1 81 in the self-locking valve 8, and a sleeve cap 85 sleeved on the sleeve rod 82 is fixed on the partition plate 2 88 by a support spring 87, and a slot 89 provided on the partition plate 2 88 is connected to the boost pipe 2. When the pressure in the boost pipe 2 is consistent with that in the feed pipe 1, the support spring 87 drives the sleeve cap 85 and the sleeve rod 82 to close, and a limiting block 86 fixedly connected in the sleeve cap 85 closes the connecting groove 84 provided on the sleeve rod 82, so that the boost pipe 2 is disconnected from the feed pipe 1, so that the driving component 4 can feed the raw material in the feed pipe 1 into the distillation tower, so that the distillation tower can purify the raw material in a stable state, and improve the stability of the pressure in the distillation tower. The device has a simple structure and is flexible to use, and is worthy of wide promotion.

[0076] The control valve 5 includes a bracket 51, and the bracket 51 is fixed on the feeding pipe 1, and a movable bar 52 is symmetrically slidably connected in the bracket 51, and a rack 1 53 is fixedly connected between the two movable bars 52, and the two racks 1 53 are meshed and connected with a linkage assembly 54, and the linkage assembly 54 includes a gear block 543, and the gear block 543 is meshed with the rack 1 53, and the bottom end of the gear block 543 is meshed with a rack 2 544, and one end of the rack 2 544 is fixedly connected with a connecting rod 545, and the connecting rod 545 is fixedly connected to the support rod 56;

[0077] Specifically, the bracket 51 in the control valve 5 is slidably connected with the movable bar 52, which drives the support rod 56 to move through the stop block 57, so that the rack 2 544 fixedly connected to the support rod 56 drives the meshing gear block 543 to rotate, and the baffle 542 arranged at the bottom end of the rack 2 544 is fixed on the limit frame 541, and the two racks 1 53 meshing with the gear block 543 drive the movable bar 52 to move relative to each other, and the pull rod 11 fixedly connected to the movable bar 52 drives the valve plate 12 to move relative to each other, so that the feed pipe 1 and the discharge port 13 opened in the distillation pipe are opened, and after the pressure in the feed pipe 1 is synchronized with the pressure in the distillation tower, the control valve 5 is passively opened, so that the raw material can be more conveniently fed into the tower, and when the raw material is safely fed into the tower, the movable rod 42 closes the discharge port 13 under the action of the reset spring 55;

[0078] The driving assembly 4 includes a hydraulic pump 41, one end of the hydraulic pump 41 is fixedly connected to a movable rod 42, one end of the movable rod 42 is fixedly connected to a pusher block 43, and the pusher block 43 is arranged in the feeding pipe 1;

[0079] Specifically, the hydraulic pump 41 in the driving assembly 4 delivers the raw materials into the distillation tower through the push block 43 via the movable rod 42, thereby improving the convenience of the device when used. The device has a simple structure and is flexible to use, and is worthy of wide promotion.

[0080] Working principle: the feed pipe 1 is connected to the distillation tower, the booster pipe 2 and the guide pipe 7 respectively, and the guide pipe 7 is connected to the external feed device. When the preset pressure is set in the distillation tower, the pressure in the constant pipe compresses the space in the connected booster pipe 2, so that the raw material in the feed pipe 1 connected to the booster pipe 2 and the pressure in the pipe are lower than the pressure in the constant pressure pipe. The booster device connected to the external pipe 6 fixedly connected to a section of the booster pipe 2 boosts the pressure in the feed pipe 1 and the booster pipe 2 to be consistent with the pressure in the distillation tower. When the pressure in the distillation tower and the constant pressure pipe is equal, the control valve 5 arranged at one end of the feed pipe 1 is passively opened, so that the drive component 4 can deliver the raw material in the feed pipe 1 into the distillation tower at the same pressure, so as to avoid the pressure imbalance in the distillation tower caused by the lack of pressure of the material, thereby reducing the purification efficiency of the distillation tower.

[0081] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A purification method for preparing semiconductor-grade metal precursors and silicon-based precursors, characterized in that: The following steps are involved: Step 1: Pressure test and leak test of purification device: pressurize the purification device with high-purity inert gas to an absolute pressure of 300-600 kPa, and then maintain the pressure for 12-48 hours. After the pressure drop of the entire purification device is ≤1%, the entire purification device is tested for helium leaks using the helium detection method, and the leak rate is ≤2*10 -10 pa.m 3 / s indicates that the air tightness of the entire purification device meets the purification requirements of metal precursors and silicon-based precursors; Step 2: gas replacement of the purification device: first use a vacuum pump to evacuate the entire purification device to an absolute pressure of ≤1Pa, then cut off the vacuum valve, open the inert gas charging valve to pressurize the purification device to an absolute pressure of 101-110kPa, repeat the above operation 3-30 times, and replace the atmosphere in the purification device with an inert gas atmosphere; Step 3: Turn on the scraped film evaporator for heating and the tower top condenser for cooling; open the scraped film evaporator heat medium inlet and outlet pipe valves, pass the heat medium to heat the scraped film evaporator to 40-200℃; open the tower top condenser refrigerant inlet and outlet pipe valves, pass the refrigerant to cool the condenser to -30-40℃; Step 4: Evacuate the purification device and control the pressure; start the vacuum pump to pump the pressure in the purification device to an absolute pressure of 0.01Pa to 60000Pa and wait for feeding; Step 5: Feeding crude metal precursor or crude silicon-based precursor; open the feed pump 2 and the feed valve 2a, 2b, 2c or 2d, and use the feed pump to transport the crude metal precursor or crude silicon-based precursor in the raw material tank 1 to the distillation tower at a constant rate of 1 to 10 kg / h.

2. A purification method for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 1, characterized in that: In the step 4, the purification device is evacuated to an absolute pressure of 0.01 to 60,000 Pa, preferably 0.1 to 50,000 Pa.

3. The method for purifying semiconductor-grade metal precursors and silicon-based precursors according to claim 1, characterized in that: The helium detection method in step 1 can be one or a combination of vacuum helium mass spectrometry leak detection, positive pressure helium mass spectrometry leak detection, vacuum pressure helium mass spectrometry leak detection, back pressure helium mass spectrometry leak detection, and the leakage rate of the purification device is required to be ≤2*10 - 10 pa.m 3 / s, preferably the leakage rate is ≤2*10 -11 pa.m 3 / s.

4. The purification method for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 1, characterized in that: The high-purity inert gas in step 1 and step 2 is one of high-purity nitrogen, high-purity argon, high-purity helium, high-purity neon, and high-purity xenon, preferably high-purity nitrogen or high-purity argon.

5. The purification method for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 1, characterized in that: The silicon-based precursor can be any one of bis(diethylamino)silane, bis(tert-butylamino)silane, diisopropylaminosilane, and tris(dimethylamino)silane; the metal precursor can be any one of tetrakis(methylethylamino)hafnium, tetrakis(methylethylamino)zirconium, tris(dimethylamino)cyclopentadienyl hafnium, tris(dimethylamino)cyclopentadienyl zirconium, tetrakis(dimethylamino)tin, tetrakis(dimethylamino)titanium, and tris(dimethylamino)n-propylcyclopentadienyl zirconium.

6. A purification device for preparing semiconductor-grade metal precursors and silicon-based precursors, characterized in that: The purification method according to any one of claims 1 to 5 is implemented, comprising a feed pipe (1) and a feed guide pipe (7) and a pressure boost pipe (2) connected thereto; A constant pressure assembly (3) is provided at one end of the boosting pipe (2), and the constant pressure pipe is connected to the distillation tower; a self-locking valve (8) is provided at the bottom end of the boosting pipe (2), and the self-locking valve (8) is connected to the feeding assembly; The boost pipe (2) maintains the pressure in the feed pipe (1) and the pressure in the distillation tower constant through the constant pressure pipe. At the same time, the constant pressure pipe controls the opening and closing of the control valve (5) at the connection between the feed pipe (1) and the distillation tower. The driving component (4) provided at one end of the feed pipe (1) guides the raw materials in the feed pipe (1) at a constant pressure into the distillation tower.

7. A purification device for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 6, characterized in that: The constant pressure tube comprises a piston block (31), and the piston block (31) is arranged in the constant pressure tube, one end of the piston block (31) is fixedly connected to a connecting shaft (33), and the other end of the piston block (31) is fixedly connected to a directional rod (32); the end of the connecting shaft (33) away from the piston block (31) is fixedly connected to a piston block (34), and the piston block (34) is arranged in the boosting tube (2); a stop block (57) is provided at the connection between the constant pressure tube and the distillation tower, one end of the stop block (57) is connected to a support rod (56), and the support rod (56) is transmission-connected to the control valve (5).

8. The purification device for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 6, characterized in that: The self-locking valve (8) comprises a partition plate 1 (81), the top end of the partition plate 1 (81) is fixedly connected to a sleeve rod (82), the top end of the sleeve rod (82) is sleeved with a sleeve cap (85), the top end of the sleeve cap (85) is fixedly connected to a support spring (87), the end of the support spring (87) away from the sleeve cap (85) is fixedly connected to a partition plate 2 (88), and the partition plate is fixed in the boost pipe (2).

9. The purification device for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 6, characterized in that: The control valve (5) comprises a bracket (51), and the bracket (51) is fixed on the feeding pipe (1), and a movable bar (52) is symmetrically slidably connected inside the bracket (51), and a rack one (53) is fixedly connected between two movable bars (52), and the two racks one (53) are meshingly connected with a linkage assembly (54), and the linkage assembly (54) comprises a gear block (543), and the gear block (543) is meshing with the rack one (53), and the bottom end of the gear block (543) is meshing with the rack two (544), and one end of the rack two (544) is fixedly connected with a connecting rod (545), and the connecting rod (545) is fixedly connected to the support rod (56).

10. The purification device for preparing semiconductor-grade metal precursors and silicon-based precursors according to claim 6, characterized in that: The driving assembly (4) comprises a hydraulic pump (41), one end of the hydraulic pump (41) is fixedly connected to a movable rod (42), one end of the movable rod (42) is fixedly connected to a pusher block (43), and the pusher block (43) is arranged in the feeding pipe (1).

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