Supercritical carbon dioxide quartz silicon material purifying and cleaning device

Abstract

The invention relates to the technical field of silicon material production and processing, in particular to a supercritical carbon dioxide quartz silicon material purifying and cleaning device, which comprises a silicon material cleaning kettle connected with supercritical carbon dioxide cleaning equipment, and further comprises flushing regulation and control equipment, the flushing regulation and control equipment is respectively connected with the silicon material cleaning kettle and the supercritical carbon dioxide cleaning equipment; the flushing regulation and control equipment comprises a regulation and control air cylinder, a compensation air hole, a basic concentration air hole and a diffusion air hole are formed in the regulation and control air cylinder, and the flushing regulation and control equipment further comprises a regulation and control assembly used for regulating the on-off states of the compensation air hole and the diffusion air hole. The cleaning state control system is located on the silicon material cleaning kettle and is in signal connection with the regulation and control assembly; the cleaning efficiency and the cleaning quality are effectively improved, the strict requirements of semiconductors and photovoltaic silicon materials for surface cleanliness are met, and the cleaning device is suitable for purifying and cleaning silicon materials of different structures.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of silicon material production and processing, and particularly relates to a supercritical carbon dioxide quartz silicon material purification and cleaning device. BACKGROUND

[0002] In the production process of semiconductor and photovoltaic grade high-purity quartz products and silicon materials, complete removal of surface contaminants is a key link to ensure the performance and reliability of the products.

[0003] Traditional wet chemical cleaning technology generally relies on a large amount of high-purity acid, alkali, solvent and ultrapure water, and has many inherent defects such as long process flow, high energy consumption, chemical reagent residue, generation of difficult-to-handle waste liquid, microstructure damage and dry spot caused by liquid surface tension, and the like, especially when processing precision parts with complex three-dimensional structures, the limitations are particularly prominent.

[0004] To overcome these difficulties, supercritical carbon dioxide cleaning technology has been introduced into this field as an advanced dry cleaning process; the core of the technology is to utilize the unique properties of supercritical carbon dioxide, which has high permeability as a gas and strong solubility as a liquid, to realize efficient and residue-free purification and cleaning through an integrated equipment system including a high-pressure pump, a cleaning main tank, a separation tank, a refrigeration unit, a precise entrainer adding system and a carbon dioxide recycling device. The typical process flow is as follows: after the workpiece to be processed is loaded into the high-pressure cleaning main tank, the system makes carbon dioxide enter the supercritical state through temperature rise and pressure increase, and injects an accurate amount of entrainer to enhance its extraction capacity for specific contaminants; then, the supercritical fluid fully penetrates and peels off the organic and inorganic contaminants on the surface of the workpiece in the circulation process; after the cleaning is completed, the fluid rich in contaminants is guided to the separation tank to precipitate impurities through pressure reduction, and the gasified carbon dioxide is condensed and liquefied for recycling, and the workpiece is dry and clean after pressure relief.

[0005] In the prior art, the traditional wet chemical cleaning technology relies on a large amount of high-purity acid, alkali, solvent and ultrapure water, and has many defects such as long process flow, high energy consumption, chemical reagent residue, generation of difficult-to-handle waste liquid, easy damage to microstructure and formation of dry spots, and the like, especially when processing precision parts with complex three-dimensional structures, the limitations are particularly prominent; and the existing supercritical carbon dioxide quartz silicon material purification and cleaning device has a fixed mode of opening and closing of the air hole, which is difficult to adapt to the cleaning requirements of silicon materials of different sizes and structures, easy to have local cleaning blind area, and has insufficient control ability for cleaning coverage, the support structure is easy to cause incomplete cleaning of the contact area of the silicon material, and the contaminants are easy to accumulate to cause secondary pollution, and therefore it is difficult to efficiently meet the stringent requirements of semiconductor and photovoltaic grade silicon materials on surface cleanliness. SUMMARY

[0006] The present application aims to provide a supercritical carbon dioxide quartz silicon material purification cleaning device to solve the problems raised in the background art.

[0007] To achieve the above object, the present application provides the following technical solutions:

[0008] A supercritical carbon dioxide quartz silicon material purification cleaning device, comprising a silicon material cleaning kettle connected with a supercritical carbon dioxide cleaning device, further comprising:

[0009] A flushing control device connected with the silicon material cleaning kettle and the supercritical carbon dioxide cleaning device respectively;

[0010] The flushing control device comprises a control air cylinder, wherein a compensation air hole, a basic concentrated air hole and a diffusion air hole are formed on the control air cylinder, and the flushing control device further comprises a control assembly for adjusting the on-off of the compensation air hole and the diffusion air hole.

[0011] A cleaning state control system located on the silicon material cleaning kettle and signal connected with the control assembly;

[0012] The cleaning state control system is used to automatically control the control assembly to change the on-off of the compensation air hole and the diffusion air hole according to the structure of the silicon material cleaning part and the cleaning coverage.

[0013] As a further scheme of the present application, the control assembly comprises:

[0014] An automatic driving ring frame rotatably installed on the silicon material cleaning kettle and driven to rotate by an external driving device, wherein the external driving device is signal connected with the cleaning state control system;

[0015] A plurality of transmission gears rotatably installed on the silicon material cleaning kettle and all meshed with the automatic driving ring frame;

[0016] A telescopic tooth plate meshed with the transmission gears;

[0017] A plugging control unit located on the control air cylinder and communicated with the compensation air hole, the basic concentrated air hole and the diffusion air hole respectively, and further fixedly connected with the telescopic tooth plate.

[0018] As a further scheme of the present application, the plugging control unit comprises:

[0019] A plurality of regulating cylinder sleeves are arranged on the regulating cylinder, and the number of the regulating cylinder sleeves is equal to the number of the transmission gears, and the plurality of regulating cylinder sleeves are uniformly distributed on the regulating cylinder;

[0020] The plugging regulating slide and the guiding slide are both slidingly installed in the regulating cylinder sleeve, and the plugging regulating slide and the guiding slide are connected through a heating connecting rod, and the regulating cylinder sleeve, the plugging regulating slide and the guiding slide form a regulating space;

[0021] In the normal working state, the supercritical carbon dioxide in the supercritical carbon dioxide cleaning equipment enters the basic concentrated air hole through the regulating space, so as to realize concentrated flushing of the silicon cleaning piece.

[0022] When the cleaning surface is increased, the plugging regulating slide is moved away from the diffusion air hole, at this time, the regulating space is connected with the basic concentrated air hole and the diffusion air hole at the same time, so as to realize diffusion flushing of the silicon cleaning piece.

[0023] The other end of the telescopic rod penetrates through the regulating cylinder sleeve and is fixedly connected with the telescopic gear plate.

[0024] As a further scheme of the present application, the heating device is fixedly installed on the plugging regulating slide and is electrically connected with the heating connecting rod.

[0025] The heating device is further connected with the cleaning state control system in signal, so as to control the temperature of the supercritical carbon dioxide.

[0026] A plurality of turbulence recesses are uniformly arranged on the heating connecting rod.

[0027] As a further scheme of the present application, the number of the compensation air holes is less than the number of the diffusion air holes, and the compensation air holes are arranged close to the bottom end of the regulating cylinder.

[0028] When part of the plugging regulating slide is moved away from the compensation air hole, at this time, part of the regulating space is connected with the compensation air hole, the basic concentrated air hole and the diffusion air hole at the same time, so as to realize compensation flushing of the silicon cleaning piece.

[0029] As a further scheme of the present application, the cleaning state control system comprises a silicon structure identification module, a cleaning coverage monitoring module, a fluid state monitoring module, a central control unit and a data storage and feedback module.

[0030] The silicon structure identification module is used for collecting the size, surface structure and three-dimensional model data of the silicon cleaning piece.

[0031] The cleaning coverage monitoring module is used for monitoring the contact area, coverage area and jetting angle of supercritical carbon dioxide and the silicon material in real time.

[0032] The fluid state monitoring module is used for monitoring the pressure, temperature and flow rate of supercritical carbon dioxide.

[0033] The central control unit is signal connected with each module and the regulating and controlling component, and is used for receiving detection data, data analysis and issuing control instructions.

[0034] The data storage and feedback module is used for storing cleaning process data and feeding back the cleaning state.

[0035] As a further scheme of the present application, the working process of the cleaning state control system comprises the following steps:

[0036] Step 1, the silicon material structure identification module collects the shape size, surface structure and total surface area data of the silicon material cleaning piece and transmits the data to the central control unit.

[0037] Step 2, the central control unit presets initial cleaning parameters according to the silicon material data.

[0038] Step 3, after the cleaning is started, the cleaning coverage monitoring module and the fluid state monitoring module collect cleaning coverage information and supercritical carbon dioxide state data in real time and transmit the data to the central control unit.

[0039] Step 4, the central control unit calculates the cleaning coverage rate and checks the supercritical carbon dioxide state parameters.

[0040] Step 5, according to the calculation and checking results, the central control unit issues action instructions to the regulating and controlling component to control the on-off state of the compensation air holes, the diffusion air holes and the basic concentrated air holes.

[0041] Step 6, the cycle monitoring and dynamic adjustment are performed at a preset period until the cleaning completion condition is met, and then the cleaning process is terminated.

[0042] As a further scheme of the present application, it further comprises a driving motor, which is signal connected with the flushing regulating and controlling device through a control line.

[0043] The control line is used for controlling the driving motor to start after the flushing regulating and controlling device is connected with supercritical carbon dioxide.

[0044] A rotating shaft, one end of which is fixedly connected with the driving motor.

[0045] A rotating cleaning platform, which is fixedly connected with the other end of the rotating shaft and is located in the silicon material cleaning kettle and used for supporting the silicon material cleaning piece to face the air holes.

[0046] As a further scheme of the present application: further comprising: fixed pillars, the number of the fixed pillars is multiple, the multiple fixed pillars are uniformly fixed and installed on the top of the rotating cleaning platform, for supporting the silicon material cleaning piece;

[0047] Reciprocating lifting pillars, the number of the reciprocating lifting pillars is multiple, the multiple reciprocating lifting pillars all penetrate the top of the rotating cleaning platform, and the bottom ends of the reciprocating lifting pillars are connected with the electromagnetic control device in the cavity on the rotating cleaning platform;

[0048] The electromagnetic control device is in signal connection with the cleaning state control system;

[0049] Among them, the multiple electromagnetic device maintenance openings are arranged at intervals with the multiple fixed pillars, when the electromagnetic control device drives the reciprocating lifting pillars to reach the highest point, the height of the top of the reciprocating lifting pillars is higher than the height of the top of the fixed pillars;

[0050] When the electromagnetic control device drives the reciprocating lifting pillars to reach the lowest point, the height of the top of the reciprocating lifting pillars is lower than the height of the top of the fixed pillars, so as to realize the alternating change of the contact points of the rotating cleaning platform and the silicon material cleaning piece;

[0051] And the electromagnetic device maintenance opening is located at the bottom end of the rotating cleaning platform and connected with the cavity.

[0052] As a further scheme of the present application: further comprising: an inclined surface, the inclined surface is arranged at the top end of the rotating cleaning platform;

[0053] And a drainage chute, the number of the drainage chute is multiple, the multiple drainage chutes are uniformly arranged on the side wall of the rotating cleaning platform, wherein one end of the drainage chute is adjacent to the inclined surface.

[0054] Compared with the prior art, the present application has the following advantages:

[0055] 1. The structure is novel, through the cooperation of the flushing control device and the cleaning state control system, the on-off of the compensation air hole, the diffusion air hole and the basic concentrated air hole can be automatically controlled according to the structure of the silicon material cleaning piece and the cleaning coverage, the flexible switching of concentrated flushing, diffusion flushing and compensation flushing is realized, the cleaning demand of different structure silicon materials is adapted, and the blind area of cleaning is effectively reduced;

[0056] 2. The cleaning state control system can monitor the silicon material structure, the cleaning coverage and the pressure, temperature, flow rate and other states of supercritical carbon dioxide in real time, dynamically adjusts the cleaning parameters through the central control unit, has high automation degree, and ensures the precise controllability of the cleaning process;

[0057] 3、The regulating assembly realizes the quick and accurate control of the opening and closing of the air hole through the cooperative action of the automatic driving ring frame, the transmission gear, the telescopic tooth plate and the blocking regulating unit, has fast response speed, small displacement error and stable cleaning effect;

[0058] 4、The heating device cooperates with the heating connecting rod to accurately control the temperature of the supercritical carbon dioxide, and the turbulence recess on the heating connecting rod can enhance the turbulence intensity of the fluid and improve the stripping capacity of the pollutants in the micropores on the surface of the silicon material;

[0059] 5、The rotary cleaning platform rotates under the driving of the driving motor, cooperates with the alternating action of the fixed pillar and the reciprocating lifting pillar, can change the contact point of the silicon material and the platform, eliminate the cleaning blind area of the contact area, and ensure that the silicon material is evenly cleaned;

[0060] 6、The slope on the rotary cleaning platform cooperates with the drainage chute to timely discharge the pollutants cleaned, reduce the secondary pollution caused by accumulation, and improve the cleaning cleanliness;

[0061] 7、The supercritical carbon dioxide can be recycled and used through related equipment, reduce the operation cost, and avoid the waste liquid pollution problem of the traditional wet cleaning, more environmentally friendly and efficient;

[0062] 8、The whole device can effectively improve the cleaning efficiency and cleaning quality, meet the strict requirements of the surface cleanliness of the semiconductor and photovoltaic grade silicon material, and is suitable for purification and cleaning of silicon materials with different structures. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 The whole process flow chart of the supercritical carbon dioxide quartz silicon material purification and cleaning device in the embodiment of the application.

[0064] Figure 2 The three-dimensional structure schematic diagram of the rotary cleaning platform in the embodiment of the application.

[0065] Figure 3 The three-dimensional structure schematic diagram of the transmission gear distribution in the embodiment of the application.

[0066] Figure 4 The three-dimensional structure schematic diagram of the fixed pillar and the reciprocating lifting pillar distribution in the embodiment of the application.

[0067] Figure 5 The three-dimensional structure schematic diagram of the electromagnetic device maintenance opening in the embodiment of the application.

[0068] Figure 6 The three-dimensional structure schematic diagram of the regulating air cylinder in the embodiment of the application.

[0069] Figure 7 The three-dimensional structure schematic diagram of the automatic driving ring frame in the embodiment of the application.

[0070] Figure 8 This is a three-dimensional structural diagram of the cylinder liner distribution control in an embodiment of the present invention.

[0071] Figure 9 This is a three-dimensional structural diagram of the blocking and regulating sliding column in an embodiment of the present invention.

[0072] Figure 10 This is a three-dimensional structural diagram of the guide slide in an embodiment of the present invention.

[0073] Figure 11 This is a system architecture block diagram of the cleaning status control system in an embodiment of the present invention.

[0074] In the diagram: 1-Silicon material cleaning tank, 2-Rinsing and regulating equipment, 3-Supercritical carbon dioxide cleaning equipment, 4-Rotating cleaning platform, 5-Drainage chute, 6-Fixed support column, 7-Reciprocating lifting support column, 8-Inclined surface, 9-Control line, 10-Regulating air cylinder, 11-Compensating air hole, 12-Drive motor, 13-Regulating cylinder liner, 14-Automatic drive ring frame, 15-Transmission gear, 16-Telescopic toothed plate, 17-Electromagnetic device inspection port, 18-Rotating shaft, 19-Foundation centralized air hole, 20-Diffusive air hole, 21-Telescopic rod, 22-Heating equipment, 23-Blocking and regulating slide column, 24-Heating connecting rod, 25-Turbulence recess, 26-Guide slide column. Detailed Implementation

[0075] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0076] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0077] Please see Figures 1-11 The present invention provides a supercritical carbon dioxide quartz silicon purification and cleaning device, comprising a silicon cleaning tank 1, wherein the silicon cleaning tank 1 is connected to a supercritical carbon dioxide cleaning device 3, and further comprising:

[0078] A rinsing control device 2 is connected to the silicon material cleaning tank 1 and the supercritical carbon dioxide cleaning device 3, respectively.

[0079] The flushing control device 2 includes a control air cylinder 10, which has a compensation air hole 11, a basic centralized air hole 19 and a diffusion air hole 20. The flushing control device 2 also includes a control component for adjusting the on / off state of the compensation air hole 11 and the diffusion air hole 20.

[0080] And a cleaning status control system, which is located on the silicon material cleaning tank 1 and is signal-connected to the control component;

[0081] The cleaning status control system is used to automatically control the operation of the regulating components according to the structure of the silicon material cleaning component and the condition of the cleaning coverage area, so as to change the on / off state of the compensation air hole 11 and the diffusion air hole 20.

[0082] In the field of semiconductor and photovoltaic silicon cleaning, the air vents of traditional supercritical carbon dioxide cleaning equipment are mostly in a fixed mode, which makes it difficult to adapt to the cleaning needs of silicon materials of different sizes and structures (such as silicon materials with deep grooves or micropores on the surface), and often results in local cleaning blind spots. In this invention, the cleaning status control system first identifies the structural characteristics of the silicon material to be cleaned (such as whether it is an irregularly shaped part, the complexity of the surface, and the size of the surface area) and the real-time cleaning coverage (such as monitoring the contact area between carbon dioxide and silicon material through infrared) by preset parameters or sensors, and then sends instructions to the control component. When processing silicon materials with simple structures that require high-intensity centralized cleaning, the control component closes the compensation air hole 11 and the diffusion air hole 20, and supercritical carbon dioxide is ejected only through the basic centralized air hole 19 to form a high-velocity jet that enhances the peeling force on local contaminants. When processing silicon materials with complex three-dimensional structures, the control component opens the diffusion air hole 20, so that carbon dioxide is ejected from the basic centralized air hole 19 and the diffusion air hole 20 at the same time, expanding the cleaning range and ensuring that areas such as deep trenches and micropores can be covered, thereby achieving targeted and adaptive cleaning control and solving the problem of poor cleaning adaptability of traditional equipment.

[0083] The supercritical carbon dioxide cleaning equipment 3 specifically includes a cryogenic carbon dioxide storage tank, a high-pressure plunger pump, a preheating heat exchanger, a precise entrainer addition system, and a carbon dioxide recycling device. The cryogenic carbon dioxide storage tank stores liquid carbon dioxide, which is then transported to the high-pressure plunger pump via pipeline. The high-pressure plunger pump pressurizes the liquid carbon dioxide to above 7.38 MPa, providing the pressure basis for it to enter the supercritical state. The pressurized carbon dioxide enters the preheating heat exchanger and is heated to above 31.1°C, forming a supercritical carbon dioxide fluid. The precise entrainer addition system can precisely add entrainers (such as ethanol, acetone, etc., with the addition amount controlled within the range of 0.1%-5%) to the supercritical carbon dioxide fluid according to the type of contaminants on the silicon material surface (such as organic residues, metal ions, etc.) using a micro-metering pump, thereby enhancing the solubility of supercritical carbon dioxide in contaminants. The carbon dioxide recycling device cools and depressurizes the carbon dioxide fluid discharged from the silicon material cleaning vessel 1 through a condensation separation system, restoring it to a liquid state. After purification, it is then transported back to the cryogenic carbon dioxide storage tank, realizing the recycling of carbon dioxide and reducing operating costs.

[0084] In one embodiment of the present invention, please refer to Figures 1-10 The control component includes:

[0085] An automatic drive ring frame 14 is rotatably mounted on the silicon material cleaning tank 1 and is driven to rotate by an external drive device, which is connected to the cleaning status control system.

[0086] The transmission gear 15 is a plurality of transmission gears, which are rotatably mounted on the silicon material cleaning tank 1 and are all meshed with the automatic drive ring frame 14.

[0087] Telescopic toothed plate 16, which meshes with the transmission gear 15;

[0088] The sealing and control unit is located on the control air cylinder 10 and is connected to the compensation air hole 11, the basic centralized air hole 19 and the diffusion air hole 20 respectively. The sealing and control unit is also fixedly connected to the telescopic toothed plate 16.

[0089] The blocking and control unit includes:

[0090] The number of regulating cylinder liners 13 is equal to the number of transmission gears 15, and the plurality of regulating cylinder liners 13 are evenly distributed on the regulating cylinder 10.

[0091] The blocking control slide 23 and the guide slide 26 are slidably installed in the control cylinder sleeve 13, and the blocking control slide 23 and the guide slide 26 are connected by a heating connecting rod 24. The control cylinder sleeve 13, the blocking control slide 23 and the guide slide 26 form a control space.

[0092] Under normal operating conditions, the supercritical carbon dioxide in the supercritical carbon dioxide cleaning equipment 3 enters the basic centralized air hole 19 through the control space to achieve centralized rinsing of the silicon material cleaning parts.

[0093] When the coverage cleaning surface is increased, the blocking control slide 23 is moved away from the diffusion air hole 20. At this time, the control space is connected to the basic centralized air hole 19 and the diffusion air hole 20 at the same time, so as to realize the diffusion rinsing of the silicon material cleaning part.

[0094] And a telescopic rod 21, one end of which is connected to the sealing and adjusting slide 23, and the other end of which passes through the adjusting cylinder liner 13 and is fixedly connected to the telescopic toothed plate 16.

[0095] Please see Figures 1-10 It also includes: a heating device 22, which is fixedly installed on the sealing and regulating slide column 23 and electrically connected to the heating connecting rod 24;

[0096] The heating device 22 is also connected to the cleaning status control system for controlling the temperature of supercritical carbon dioxide.

[0097] And a plurality of turbulence recesses 25, wherein the plurality of turbulence recesses 25 are evenly distributed on the heating connecting rod 24.

[0098] The number of compensation air holes 11 is less than the number of diffusion air holes 20, and the compensation air holes 11 are located near the bottom of the regulating air cylinder 10.

[0099] When the partially blocked control slide 23 moves away from the compensation air hole 11, at this time, part of the control space is simultaneously connected to the compensation air hole 11, the basic centralized air hole 19 and the diffusion air hole 20, so as to realize the compensation rinsing of the silicon material cleaning component.

[0100] In the field of supercritical carbon dioxide cleaning, traditional equipment often uses a single drive structure for vent control, making it difficult to achieve synchronous and precise control of multiple vents. Furthermore, the stability of the carbon dioxide fluid state significantly affects the cleaning effect. In this invention, the control components achieve efficient coordination through multi-stage transmission: the automatic drive ring frame 14 uses an inner gear ring structure that meshes with the output gear of an external servo motor (external drive device), with its rotational accuracy controllable within ±0.5°, ensuring transmission stability; multiple transmission gears 15 (e.g., 8, evenly distributed in a ring) mesh with the gear ring of the automatic drive ring frame 14, converting rotational motion into linear motion of the telescopic gear plate 16. The telescopic gear plate 16 uses a high-precision guide rail, with a displacement error ≤0.1mm, ensuring the accuracy of the sealing control. In the sealing and control unit, the inner wall of the control cylinder liner 13 is provided with a wear-resistant coating (such as a titanium nitride coating). The clearance between the control cylinder liner 13 and the sealing and control slide 23 and the guide slide 26 is controlled at 0.02-0.05mm, and a V-ring sealing structure is adopted to prevent supercritical carbon dioxide leakage. The position of the control space can be adjusted by the position of the slide liner. When the sealing and control slide liner 23 closes the diffuser hole 20, the control space is close to the innermost side of the control cylinder liner 13, and carbon dioxide is ejected through the basic centralized air hole 19 with a flow rate of 15-20m / s to achieve centralized high-pressure flushing. When the slide liner is moved away, the position of the control space changes, and in conjunction with the fan-shaped distribution (60° included angle) of the diffuser hole 20, a wide-coverage diffusion flushing is formed. Meanwhile, the heating device 22 uses armored heating wire (power 50-200W). Through PID adjustment of the cleaning status control system, the carbon dioxide temperature can be stably controlled at 31.1-60℃ (accuracy ±0.5℃). The heating connecting rod 24 is made of copper alloy to enhance thermal conductivity. Its surface turbulence indentations 25 (diameter 3-5mm, depth 1-2mm, spiral distribution) can generate intense turbulence in the carbon dioxide fluid, with turbulence intensity more than 30% higher than that of a smooth connecting rod. This significantly enhances the ability to remove contaminants from the micropores (diameter ≤10μm) on the silicon surface, while ensuring sufficient heating of the carbon dioxide gas. The telescopic rod 21 is made of high-strength alloy steel and can withstand pressures of over 10MPa, ensuring stable power transmission under high pressure and enabling rapid switching of the on / off states of each air hole (response time ≤0.5s). This improves the overall adaptability of the device to complex silicon structures and cleaning efficiency.

[0101] Furthermore, in silicon material cleaning practices, due to limitations imposed by gravity and the carbon dioxide spray angle, traditional equipment often has a weaker cleaning effect on the lower part of the silicon material (such as the bottom end of a silicon rod with a diameter of 50mm or more) than on the upper part, easily leading to contaminant residue. In this invention, the number of compensation air holes 11 is less than that of diffusion air holes 20 (for example, there are 8 diffusion air holes 20 and 5 compensation air holes 11), and they are concentrated within a 180° range at the bottom of the control air cylinder 10, forming a directional supplementary spray area. When the cleaning status control system detects through image recognition or pressure sensors that the cleaning coverage of the lower part of the silicon material is lower than a preset threshold (e.g., 80%), it controls the blocking control slide 23 to move outward along the control cylinder liner 13, thereby opening the compensation air hole 11. At this time, while maintaining the injection of the basic concentrated air hole 19 and the diffusion air hole 20, the supercritical carbon dioxide in part of the control space forms a downward-sloping supplementary jet through the compensation air hole 11. Its flow rate is 15-20% higher than that of the diffusion air hole 20 (due to the small opening area), which can enhance the impact force on the gaps and corners of the lower part of the silicon material. It complements the upper coverage of the diffusion air hole 20, ensuring that the cleaning effect of the silicon material is consistent throughout its entire length from top to bottom, meeting the stringent requirements of semiconductor-grade silicon material for surface cleanliness (e.g., contaminant particle size ≤0.1μm).

[0102] In one embodiment of the present invention, please refer to Figures 1-11 The cleaning status control system includes (the following components can be installed in appropriate positions in the silicon material cleaning tank 1 as needed, as long as they can perform normal detection functions; their specific installation positions are not limited here):

[0103] Silicon Material Structure Recognition Module: Includes a high-definition industrial image sensor (resolution ≥ 12 million pixels) and a 3D structured light scanner, used to collect the external dimensions, surface structure (such as deep grooves, micropore distribution) and three-dimensional model data of silicon material cleaning parts, and to identify whether the silicon material is an irregularly shaped part, the complexity of the surface and the size of the surface area.

[0104] Cleaning coverage monitoring module: It consists of an infrared thermal imager (temperature range 30-80℃, accuracy ±0.5℃) and a laser displacement sensor (measurement range 0-500mm, accuracy ±0.01mm), which monitors the contact area, coverage area and spray angle of supercritical carbon dioxide and silicon material in real time.

[0105] Fluid state monitoring module: includes a pressure sensor (measurement range 0-30MPa, accuracy ±0.05MPa), a temperature sensor (measurement range 20-100℃, accuracy ±0.1℃) and a mass flow sensor (measurement range 0-5kg / h, accuracy ±0.5%), which monitor the pressure, temperature and flow rate of supercritical carbon dioxide, respectively.

[0106] Central control unit: adopts an industrial-grade PLC controller (response time ≤ 0.1ms), which is connected to the above modules and control components (automatic drive ring frame, transmission gears, etc.) to receive detection data, perform data analysis and issue control commands;

[0107] Data storage and feedback module: Includes solid-state drive (storage capacity ≥1TB) and touch screen, used to store cleaning process data (such as silicon material parameters, real-time monitoring values, and control commands), and can provide real-time feedback on the cleaning status through the display screen.

[0108] The specific workflow of the cleaning status control system includes the following steps:

[0109] 1. Silicon material information collection and initial identification;

[0110] After the silicon material is placed on the rotary cleaning platform 4, the silicon material structure recognition module is activated. It uses a high-definition image sensor and a 3D structured light scanner to collect the silicon material's external dimensions (such as length L and diameter D), surface structure features (such as micropore diameter d and trench depth h), and total surface area S. total The data is transmitted to the central control unit and stored;

[0111] 2. Initial cleaning parameters preset;

[0112] The central control unit is based on the total surface area S of the silicon material. total And the surface complexity (e.g., micropore density ρ = number of micropores / unit area), preset initial cleaning parameters: including the initial pressure P0 of supercritical carbon dioxide (based on silicon volume V = π(D / 2)). 2 L, with P0 = k1 × V, where k1 is the pressure coefficient, ranging from 0.02 to 0.05 MPa / cm. 3 ), initial temperature T0 (35-40℃) and initial opening status of the foundation centralized air vents.

[0113] 3. Real-time cleaning status monitoring;

[0114] After the cleaning process is initiated, the cleaning coverage monitoring module acquires the cleaned area S in real time using an infrared thermal imager. cleansed The laser displacement sensor monitors the distance Δx between the silicon material surface and the injection nozzle; the fluid state monitoring module simultaneously collects the real-time pressure P, temperature T and flow rate Q of supercritical carbon dioxide and transmits the data to the central control unit in real time.

[0115] 4. Calculation and judgment of cleaning coverage;

[0116] The central control unit calculates the cleaning coverage rate using the following formula:

[0117]

[0118] Where η is the cleaning coverage rate (unit: %), S cleansed The cleaned area is monitored in real time (unit: cm). 2 ), S total The total surface area of ​​silicon material obtained in step 1 (unit: cm²) 2 );

[0119] If η < 80% (preset threshold), it is determined that there is a cleaning blind spot and the cleaning range needs to be expanded; if η ≥ 95%, it is determined that the coverage is sufficient and the current state can be maintained or the local cleaning intensity can be increased.

[0120] 5. Fluid state stability verification;

[0121] To ensure that supercritical carbon dioxide is in a stable supercritical state (temperature ≥ 31.1℃, pressure ≥ 7.38MPa), the central control unit verifies the state parameters using the following formula:

[0122] △P=|PP cr |,△T=|TT cr |;

[0123] Where P is the real-time pressure (unit: MPa), P cr The critical pressure of carbon dioxide is 7.38 MPa; T is the real-time temperature (unit: °C). cr This is the critical temperature for carbon dioxide (31.1℃).

[0124] If ΔP > 0.5 MPa or ΔT > 2℃, then adjust using heating device 22 and high-pressure plunger pump to make ΔP ≤ 0.3 MPa and ΔT ≤ 1℃.

[0125] 6. Control component action command issued;

[0126] When the silicon material has a simple structure (no deep trenches / micropores, ρ < 5 particles / cm) 2 When η≥90%, the central control unit commands the automatic drive of the ring frame 14 to rotate, which drives the telescopic tooth plate 16 to retract through the transmission gear 15, so that the sealing control slide column 23 closes the compensation air hole 11 and the diffusion air hole 20, leaving only the basic centralized air hole 19 open, thereby enhancing the local flushing intensity (the flow rate is increased to 18-20m / s).

[0127] When silicon material has a complex structure (with deep grooves / micropores, ρ≥5 pores / cm) 2 When η < 80%, the control slide 23 is moved away to open the diffuser 20, so that supercritical carbon dioxide is ejected from the base central air hole 19 and the diffuser 20 at the same time (diffuser injection angle 60°), thus expanding the coverage area.

[0128] When the laser displacement sensor detects that the lower part of the silicon material (the area ≤1 / 3L from the platform surface) Δx > preset value (e.g., 50mm) and η < 70%, it commands the opening of the compensation air hole 11 to form a downward-sloping supplementary jet (the flow rate is 15% higher than that of the diffusion air hole) to compensate for the lower cleaning blind area.

[0129] 7. Circular monitoring and dynamic adjustment;

[0130] With a monitoring cycle of 5 seconds, steps 3-6 are repeated. The central control unit dynamically adjusts the action of the control components and the state parameters of supercritical carbon dioxide based on real-time data until η≥95% and ΔP≤0.3MPa and ΔT≤1℃ for three consecutive cycles.

[0131] 8. Determining and terminating the cleaning process;

[0132] The central control unit determines that cleaning is complete when the following conditions are met: ① η ≥ 98% for 5 consecutive cycles; ② Concentration of pollutants in supercritical carbon dioxide (detected by an online laser particle size analyzer) ≤ 0.1 mg / m³. 3 ③ The cleaning time reaches the preset duration (based on S). total t=k2×S total k2 is the time coefficient, with a value ranging from 0.01 to 0.03 h / cm. 2 Subsequently, the control component was instructed to close all air vents, and the supercritical carbon dioxide cleaning equipment stopped supplying liquid and entered the recovery process.

[0133] Through the above components and workflow, the cleaning status control system achieves fully automated and precise control of the silicon material cleaning process, effectively solving problems such as poor adaptability and local blind spots of traditional equipment, and ensuring that the surface cleanliness of semiconductor and photovoltaic grade silicon materials meets stringent requirements.

[0134] In one embodiment of the present invention, please refer to Figures 1-11 It also includes: a drive motor 12, which is connected to the flushing control device 2 via a control line 9;

[0135] The control line 9 is used to control the start of the drive motor 12 after supercritical carbon dioxide is introduced into the flushing control device 2;

[0136] A rotating shaft 18, one end of which is fixedly connected to the drive motor 12;

[0137] And a rotating cleaning platform 4, which is fixedly connected to the other end of the rotating shaft 18, and the rotating cleaning platform 4 is located inside the silicon material cleaning tank 1, for supporting the silicon material cleaning component facing the air hole.

[0138] It also includes: a fixed support column 6, wherein there are multiple fixed support columns 6, which are evenly fixedly installed on the top of the rotary cleaning platform 4 to support the silicon material cleaning component;

[0139] The reciprocating lifting support column 7 is a plurality of such columns, and all such columns 7 penetrate the top of the rotary cleaning platform 4. The bottom ends of the reciprocating lifting support columns 7 are connected to the electromagnetic control device in the cavity of the rotary cleaning platform 4.

[0140] The electromagnetic control device is signal-connected to the cleaning status control system.

[0141] Among them, multiple electromagnetic device inspection ports 17 are spaced apart from multiple fixed support columns 6. When the electromagnetic control device drives the reciprocating lifting support column 7 to reach the highest point, the height of the top of the reciprocating lifting support column 7 is higher than the height of the top of the fixed support column 6.

[0142] When the electromagnetic control device drives the reciprocating lifting column 7 to the lowest point, the height of the top of the reciprocating lifting column 7 is lower than the height of the top of the fixed column 6, so as to alternately change the contact point between the rotating cleaning platform 4 and the silicon cleaning component.

[0143] And an electromagnetic device access port 17, which is located at the bottom of the rotating cleaning platform 4 and connected to the cavity.

[0144] It also includes: an inclined surface 8, which is disposed at the top of the rotary cleaning platform 4;

[0145] And a plurality of diversion troughs 5, wherein the plurality of diversion troughs 5 are evenly provided on the side wall of the rotating cleaning platform 4, wherein one end of the diversion trough 5 is adjacent to the inclined surface 8.

[0146] Passed. In traditional silicon material cleaning, the static placement of silicon material can easily lead to cleaning blind spots in the area in contact with the support components, and the detached contaminants can easily accumulate on the platform, causing secondary pollution. In this invention, when supercritical carbon dioxide is introduced into the rinsing control device 2 (system pressure reaches above 5MPa), the control line 9 triggers the drive motor 12 (such as a stepper motor) to start. The drive motor 12 drives the rotating cleaning platform 4 to rotate smoothly at a speed of 5-10r / min through the rotating shaft 18, so that the silicon material cleaning components are evenly aligned with each air hole in the circumference, avoiding uneven cleaning caused by spraying in one direction. The fixed support column 6 (50mm high) on the rotary cleaning platform 4 initially supports the silicon material. Simultaneously, the cleaning status control system, according to the cleaning progress (e.g., every 30 seconds), drives the reciprocating lifting column 7 (80mm stroke) in alternating motion via electromagnetic control equipment. When it reaches its highest point (30mm above the fixed support column 6), the silicon material is lifted and detached from the fixed support column 6, completely exposing the previously contacted area. When it descends to its lowest point (below the fixed support column 6), the silicon material falls back onto the fixed support column 6, achieving dynamic switching of the contact point and eliminating cleaning blind spots (and through the compensation air vents 11, the contact area can be cleaned quickly, ensuring consistent cleaning results). The inclined surface 8 (15° inclination angle) at the top of the rotary cleaning platform 4 cooperates with the drainage trough 5 (20mm wide, 15mm deep) on the side wall, allowing contaminants (such as metal ions and particles) to slide along the inclined surface 8 into the drainage trough 5 under the action of centrifugal force and gravity, ultimately being discharged to the recovery channel at the bottom of the silicon material cleaning tank 1, preventing accumulation and contamination. The electromagnetic device inspection port 17 (100mm in diameter) can be opened periodically to maintain and calibrate the electromagnetic control equipment, ensuring the accuracy of the reciprocating lifting support column 7 (error ≤ 0.5mm), improving overall cleaning efficiency and cleanliness, and meeting the standard of ≤ 10ppb content of metallic impurities on the surface of photovoltaic-grade silicon material.

[0147] The electromagnetic control equipment is signal-connected to the cleaning status control system. The electromagnetic control equipment includes an electromagnet, a return spring, a lifting plate, and a guide sleeve. All of these components are existing technologies. The electromagnet is fixedly installed at the bottom of the cavity of the rotating cleaning platform 4. The lifting plate is located above the electromagnet and fixedly connected to the bottom end of the reciprocating lifting support column 7. The return spring is sleeved on the outside of the reciprocating lifting support column 7, with its two ends abutting against the lifting plate and the inner wall of the top of the cavity, respectively. The guide sleeve is fixed at the through hole of the rotating cleaning platform 4 and slides in cooperation with the reciprocating lifting support column 7.

[0148] Under the control of the cleaning status control system, the current change of the electromagnet adopts a stepped increasing / decreasing mode. In the initial stage, the current slowly increases from 0 to 30% of the rated current (lasting 0.5-1 second), gradually increasing the electromagnetic attraction on the lifting plate and driving the reciprocating lifting support 7 to slowly rise against the spring force of the return spring. In the middle stage, the current is maintained in a stable change within the range of 30%-80% (speed ≤0.2A / s), ensuring uniform lifting and lowering of the support. When approaching the highest / lowest point, the current decreases to 0 or increases to the rated value at a rate of 0.1A / s, achieving buffer braking. Through this current control method, the lifting speed of the reciprocating lifting support 7 can be controlled at 5-10mm / s, and the acceleration ≤2mm / s². 2 It effectively prevents silicon cleaning parts from slipping or shifting due to sudden displacement, and is especially suitable for stable support of cylindrical silicon materials or irregularly shaped quartz parts with a diameter of 50-200mm.

[0149] It should be noted that, in this invention, unless otherwise explicitly specified and limited, the terms "sliding," "rotating," "fixed," and "equipped" should be interpreted broadly. For example, they can refer to welded connections, bolted connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0150] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A supercritical carbon dioxide quartz silica purification and cleaning device, comprising a silica cleaning tank, wherein the silica cleaning tank is connected to a supercritical carbon dioxide cleaning device, characterized in that, Also includes: A rinsing and control device is provided, which is connected to both the silicon material cleaning tank and the supercritical carbon dioxide cleaning device. The flushing control device includes a control air cylinder, which has a compensation air hole, a basic centralized air hole and a diffusion air hole. The flushing control device also includes a control component for adjusting the opening and closing of the compensation air hole and the diffusion air hole. And a cleaning status control system, which is located on the silicon material cleaning tank and is signal-connected to the control component; The cleaning status control system is used to automatically control the operation of the regulating components according to the structure of the silicon material cleaning component and the condition of the cleaning coverage area, so as to change the opening and closing of the compensation air hole and the diffusion air hole.

2. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 1, characterized in that, The control component includes: An automatic drive ring frame is rotatably mounted on the silicon material cleaning tank and is driven to rotate by an external drive device, which is connected to the cleaning status control system. The transmission gears are multiple in number, and the multiple transmission gears are rotatably mounted on the silicon material cleaning tank and are all meshed with the automatic drive ring frame; A telescopic toothed plate, which meshes with the transmission gear; The system also includes a blocking control unit located on the control air cylinder and connected to the compensation air hole, the base centralized air hole, and the diffusion air hole, respectively. The blocking control unit is also fixedly connected to the telescopic toothed plate.

3. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 2, characterized in that, The blocking and control unit includes: The number of regulating cylinder liners is equal to the number of transmission gears, and the plurality of regulating cylinder liners are evenly distributed on the regulating cylinder. The control slide and guide slide are slidably installed in the control cylinder sleeve, and the control slide and guide slide are connected by a heating link. The control cylinder sleeve, the control slide and guide slide form a control space. Under normal operating conditions, the supercritical carbon dioxide in the supercritical carbon dioxide cleaning equipment enters the basic centralized air hole through the control space to achieve centralized rinsing of the silicon material cleaning parts. When increasing the coverage cleaning area, the blocking control slide is moved away from the diffusion air hole. At this time, the control space is connected to both the basic centralized air hole and the diffusion air hole to achieve diffusion rinsing of the silicon material cleaning part. And a telescopic rod, one end of which is connected to the sealing and adjusting slide column, and the other end of which passes through the adjusting cylinder liner and is fixedly connected to the telescopic toothed plate.

4. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 3, characterized in that, Also includes: A heating device, which is fixedly installed on the sealing and regulating sliding column and electrically connected to the heating connecting rod; The heating device is also connected to the cleaning status control system for controlling the temperature of supercritical carbon dioxide. And turbulence recesses, wherein there are multiple turbulence recesses, and the multiple turbulence recesses are evenly formed on the heating connecting rod.

5. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 3 or 4, characterized in that, The number of compensation air holes is less than the number of diffusion air holes, and the compensation air holes are located near the bottom of the regulating air cylinder; When the partially blocked control slide is moved away from the compensation air hole, at this time, part of the control space is simultaneously connected to the compensation air hole, the basic centralized air hole and the diffusion air hole, so as to realize the compensation rinsing of the silicon material cleaning component.

6. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 4, characterized in that, The cleaning status control system includes a silicon material structure identification module, a cleaning coverage monitoring module, a fluid status monitoring module, a central control unit, and a data storage and feedback module. Among them, the silicon material structure recognition module is used to collect the external dimensions, surface structure and three-dimensional model data of the silicon material cleaning parts; The cleaning coverage monitoring module is used to monitor the contact area, coverage area and spray angle between supercritical carbon dioxide and silicon material in real time. The fluid state monitoring module is used to monitor the pressure, temperature, and flow rate of supercritical carbon dioxide; The central control unit is connected to each module and control component via signals, and is used to receive detection data, analyze data, and issue control commands. The data storage and feedback module is used to store cleaning process data and provide feedback on the cleaning status.

7. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 6, characterized in that, The workflow of the cleaning status control system includes the following steps: Step 1: The silicon material structure recognition module collects the external dimensions, surface structure, and total surface area data of the silicon material cleaning part and transmits them to the central control unit. Step 2: The central control unit presets the initial cleaning parameters based on the silicon material data; Step 3: After the cleaning is started, the cleaning coverage monitoring module and the fluid state monitoring module collect cleaning coverage information and supercritical carbon dioxide state data in real time and transmit them to the central control unit. Step 4: The central control unit calculates the cleaning coverage and verifies the supercritical carbon dioxide state parameters; Step 5: Based on the calculation and verification results, the central control unit sends action commands to the control components to control the on / off status of the compensation air vents, diffusion air vents and foundation centralized air vents. Step 6: Monitor and dynamically adjust the process in a preset cycle until the cleaning completion conditions are met, then control the cleaning process to terminate.

8. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 1, characterized in that, Also includes: A drive motor, wherein the drive motor is connected to the flushing control device via a control line; The control line is used to control the start of the drive motor after supercritical carbon dioxide is introduced into the flushing control equipment. A rotating shaft, one end of which is fixedly connected to the drive motor; And a rotary cleaning platform, which is fixedly connected to the other end of the rotary shaft, and the rotary cleaning platform is located inside the silicon material cleaning tank to support the silicon material cleaning parts facing the air holes.

9. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 8, characterized in that, Also includes: A plurality of fixed supports are uniformly fixedly installed on the top of the rotary cleaning platform to support the silicon material cleaning components. The reciprocating lifting support column is multiple in number, and all of the multiple reciprocating lifting support columns penetrate through the top of the rotating cleaning platform. The bottom end of each reciprocating lifting support column is connected to the electromagnetic control device inside the cavity of the rotating cleaning platform. The electromagnetic control device is signal-connected to the cleaning status control system. The electromagnetic device inspection ports are spaced apart from the fixed support columns. When the electromagnetic control device drives the reciprocating lifting support column to the highest point, the height of the top of the reciprocating lifting support column is higher than the height of the top of the fixed support column. When the electromagnetic control device drives the reciprocating lifting column to the lowest point, the height of the top of the reciprocating lifting column is lower than the height of the top of the fixed column, so as to alternately change the contact point between the rotating cleaning platform and the silicon cleaning component. And an electromagnetic device access port, which is located at the bottom of the rotating cleaning platform and connected to the cavity.

10. The supercritical carbon dioxide quartz silica purification and cleaning device according to claim 9, characterized in that, Also includes: An inclined plane is provided at the top of the rotating cleaning platform; And a plurality of diversion troughs, wherein the plurality of diversion troughs are evenly provided on the side wall of the rotating cleaning platform, wherein one end of the diversion trough is adjacent to the inclined surface.

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