Equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid

Abstract

The utility model discloses a device for recovering silicon powder from semiconductor silicon wafer processing cutting fluid, which comprises a working table, two groups of supporting legs are symmetrically arranged at the bottom of the working table, a fixing frame is fixedly arranged at the top of the working table, a controller is arranged on one side of the bottom of the working table, and the controller is connected with the supporting legs. The device is characterized in that a positioning frame is fixedly installed at the position, located below the fixing frame, of the top of the workbench, an ultrasonic generator is fixedly installed in the center of the bottom of the workbench, a separation and recovery assembly is arranged below the fixing frame, and positioning assemblies are arranged in and above the positioning frame; the separating and recycling assembly comprises a movable plate arranged on the upper portion in the fixing frame. After a silicon wafer is cut, the silicon powder in the cutting fluid can be effectively separated and recycled, and the problems that the silicon powder in the waste cutting fluid is difficult to separate and recycle, the disposal cost is high and resources are wasted are solved. The equipment is simple to operate, and the practicability is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of waste cutting fluid resource, specifically to a kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid. BACKGROUND

[0002] In the current semiconductor industry wafer production process, cutting fluid will be used a lot. At present, diamond wire cutting is used as mainstream technology to slice silicon ingot, because the thickness of silicon wafer is similar to the diameter of cutting wire, so at least more than 30% of crystalline silicon is cut and ground into silicon powder, which is mixed into cutting fluid. This not only causes a large amount of crystalline silicon loss, reduces product output rate, but also reduces the performance of cutting fluid by mixing silicon powder into cutting fluid, which increases production cost. And the purity of these worn silicon powder is very high, which can reach 99.99%, so the recycling value is high.

[0003] In terms of recycling, the waste cutting fluid is mixed with a large amount of silicon powder, but because the silicon powder is micron-sized particle size, it still has similar properties to cutting fluid, strong surface adsorption, high surface energy, high chemical purity, good dispersion performance, high stability of molecular system in cutting fluid, and the addition of a large amount of surfactants, stabilizers and other components in cutting fluid makes it have excellent stability. Therefore, the difficulty coefficient of recycling silicon powder from waste cutting fluid is increased, so the resource is basically in the state of harmless disposal or low-value utilization.

[0004] A kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid is proposed to solve the problems raised in the above. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid to solve the problems raised in the above background technology due to the stable chemical properties of waste cutting fluid system, small particle size, good dispersion and high stability of silicon powder, which leads to large separation and recovery difficulty. At the same time, efficient separation and recovery of silicon powder from waste cutting fluid also solves the problems of crystalline silicon waste, high production cost and waste cutting fluid only harmless disposal.

[0006] To achieve the above purpose, the utility model provides the following technical scheme: a kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid, including workbench;

[0007] Two groups of supporting legs are symmetrically installed at the bottom of the workbench, and a fixed frame is fixedly installed at the top of the workbench, and a controller is arranged at one side of the bottom of the workbench;

[0008] It also includes:

[0009] The top of the workbench is fixedly installed with a positioning frame below the fixed frame, the bottom center of the workbench is fixedly installed with an ultrasonic generator, the lower part of the fixed frame is provided with a separation assembly, and the inside and upper part of the positioning frame are provided with a positioning assembly.

[0010] The separation assembly comprises a movable plate provided above the inside of the fixed frame, one side of the movable plate is fixedly installed with a threaded sleeve, the inside of the threaded sleeve is threadedly connected with a threaded rod, and the two ends of the threaded rod are rotationally connected with the fixed frame and the workbench respectively.

[0011] The top side of the fixed frame is fixedly installed with a driving motor, the output end of the driving motor is fixedly connected with the threaded rod through the fixed frame, the other side of the movable plate is symmetrically installed with a movable sleeve, the inside of the two movable sleeves is slidably connected with a support rod, and the two ends of the two support rods are fixedly connected with the fixed frame and the workbench respectively.

[0012] Preferably, the top center of the movable plate is fixedly installed with a stirring motor, the output end of the stirring motor is fixedly installed with a stirring shaft through the movable plate, and the outside of the stirring shaft is symmetrically installed with a plurality of stirring rods.

[0013] Preferably, the bottom of the movable plate is fixedly installed with an ultrasonic vibration rod on one side of the stirring shaft.

[0014] Preferably, the top side of the movable plate is fixedly installed with a liquid storage tank, a liquid outlet pipe is provided through the side and lower part of the liquid storage tank, the liquid outlet pipe is connected with the movable plate in a penetrating manner, and the outside of the liquid outlet pipe is provided with an electromagnetic valve below.

[0015] Preferably, the positioning assembly comprises positioning plates symmetrically provided in the inside of the positioning frame, limit rods are symmetrically installed on the sides away from each other of the two positioning plates, the limit rods are slidably connected with the positioning frame, a return spring is sleeved on the outside of one side of the limit rod, one end of the return spring is fixedly connected with the positioning frame, the other end of the return spring is fixedly connected with the limit rod, the top of each of the two positioning plates is fixedly installed with a vertical rod, one side of the vertical rod is fixedly installed with a guide rod, the outside of one side of the guide rod is slidably connected with a mounting frame, and the mounting frame is fixedly connected with the positioning frame.

[0016] Preferably, the top of each of the two vertical rods is hingedly connected with a rotating rod, a torsional spring is arranged at the connection between the rotating rod and the vertical rod, and a column block is fixedly installed on the upper part of one side of the rotating rod.

[0017] Preferably, the bottom of the movable plate is symmetrically provided with two groups of fixed blocks on both sides, and a fixed rod is fixedly arranged between each group of two fixed blocks, and a movable block is slidably connected to the outside of the fixed rod, and a telescopic spring is sleeved on one side of the outside of the fixed rod, one end of the telescopic spring is fixedly connected with one side of the fixed block, the other end of the telescopic spring is fixedly connected with the movable block, and a fixed seat is fixedly arranged at the bottom of the movable block, and the column block is adaptively connected with the fixed seat.

[0018] The utility model discloses a kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid, and movable separation assembly is arranged below fixed frame, silicon powder in waste cutting fluid can be efficiently separated, and silicon powder recovery is facilitated.

[0019] 1. When the cutting fluid is recycled, the waste cutting fluid is placed in the square box, and is transferred to the upper part of the workbench by the forklift, so that the rear side of the square box is attached to the positioning frame. Then, the driving motor is started to drive the threaded rod to rotate, which in turn drives the threaded sleeve to move, causing the movable plate to descend. The movable plate moves and drives the movable sleeve to slide on the support rod to limit the movement, causing the stirring shaft to insert into the square box and the ultrasonic vibration rod to insert into the square box. The calcium chloride solution is stored in the liquid storage tank, and the amount of calcium chloride added to the square box is controlled by the electromagnetic valve on the liquid outlet pipe. The stirring motor drives the stirring rod to rotate, stirring the waste cutting fluid, making it fully homogeneous, and accelerating the reaction. By adding a certain proportion of calcium chloride to the reaction system, the calcium chloride dissociates into positive and negative ions after being added to the system, and a strong hydration effect occurs, which reduces the number of free water molecules in the liquid and dehydrates the system, thereby destroying the stable phase structure of the molecules. After adding calcium chloride to the cutting fluid containing a surfactant, Ca+ compresses the double electric layer, reduces the zeta potential, and reduces the mutual repulsive force between silicon molecules, destroying the stability of the molecules and making them lose their stable state. Under the action of van der Waals force, it may collide and become dispersed, and then have sedimentation properties.

[0020] The ultrasonic generator is also started, and the strong cavitation effect, disturbance effect, high acceleration, crushing and stirring effect, and other multi-level effects produced by the ultrasonic radiation pressure are used to increase the molecular motion frequency and speed of the substances in the waste cutting fluid, increase the solvent penetration, and accelerate the separation of silicon powder and solvent, promoting the instability and sedimentation of silicon powder. After the ultrasonic reaction is completed, the waste cutting fluid square box is transferred from the workbench, and the separated waste cutting fluid is allowed to stand and separate. The supernatant is transferred to the sewage station for treatment, and the silicon powder is recovered. This makes it easy to effectively separate the silicon powder in the cutting fluid after cutting the silicon wafer, recover the silicon powder, and solve the problem of high disposal cost and resource waste of waste cutting fluid silicon powder separation. The equipment is easy to operate, and the practicality is improved.

[0021] 2. When positioning the square box, the rear side of the square box is attached to the positioning frame, then the movable plate is lowered to drive the fixing seat to be lowered, the fixing seat is lowered to be clamped outside the column block, then the movable plate continues to be lowered to push the rotating rod to rotate, the rotating rod rotates to push the positioning plate to move through the vertical rod, so that the limiting rod slides on the positioning frame and compresses the reset spring, so that the two positioning plates are attached to the two sides of the square box, then the movable plate continues to be lowered to make the movable block slide on the fixed rod, and the extension spring can be stretched, so that the movable plate can move after positioning the square box, through the positioning assembly, the user can conveniently fix the square box, and displacement of the square box in actual production is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a front structure schematic view of the utility model;

[0023] Figure 2 It is a movable plate moving structure schematic view of the utility model;

[0024] Figure 3 It is a positioning frame top view structure schematic view of the utility model;

[0025] Figure 4 It is a positioning frame top view structure schematic view of the utility model; Figure 2 It is a A area enlarged structure schematic view of the utility model;

[0026] Figure 5 It is a B area enlarged structure schematic view of the utility model; Figure 2

[0027] In the drawing: 1, workbench; 101, support leg; 102, fixed frame; 103, positioning frame; 104, ultrasonic generator; 2, separation and recovery assembly; 201, movable plate; 202, threaded rod; 203, drive motor; 204, threaded sleeve; 205, movable sleeve; 206, support rod; 207, stirring motor; 208, stirring shaft; 209, stirring rod; 210, ultrasonic vibration rod; 211, liquid storage tank; 212, liquid outlet pipe; 3, positioning assembly; 301, positioning plate; 302, limiting rod; 3021, reset spring; 303, vertical rod; 304, mounting frame; 305, guide rod; 306, rotating rod; 3061, column block; 307, torsional spring; 308, fixed block; 309, fixed rod; 310, movable block; 311, extension spring; 312, fixing seat. DETAILED DESCRIPTION

[0028] ​Clearly, the described embodiments are merely a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] Please refer to Figures 1-5 The utility model provides technical scheme: a kind of equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid, including workbench 1, the bottom of the workbench 1 is symmetrically equipped with two groups of supporting legs 101, and the top of workbench 1 is fixedly installed with fixed frame 102, and the bottom of workbench 1 side is provided with controller, further comprising: the top of the workbench 1 is fixedly installed with positioning frame 103 below fixed frame 102, and the bottom center of workbench 1 is fixedly installed with ultrasonic generator 104, specifically QYCF ultrasonic generator, as prior art is used, and the below of fixed frame 102 is provided with separation recovery subassembly 2, and the inside and top of positioning frame 103 are provided with positioning assembly 3, wherein the separation recovery subassembly 2 includes movable plate 201 being arranged in the inside top of fixed frame 102, and the side of movable plate 201 is fixedly installed with threaded sleeve 204, and the inside of threaded sleeve 204 is threadedly connected with threaded rod 202, and the two ends of threaded rod 202 are rotatably connected with fixed frame 102 and workbench 1 respectively, wherein the top of fixed frame 102 side is fixedly installed with driving motor 203, and the output end of driving motor 203 is fixedly connected with threaded rod 202 through fixed frame 102, and the other side of movable plate 201 is symmetrically installed with movable sleeve 205, and the inside of two movable sleeves 205 is slidably connected with support rod 206, and the two ends of two support rods 206 are fixedly connected with fixed frame 102 and workbench 1 respectively, so that after cutting silicon wafer, it is convenient to effectively separate silicon powder in cutting fluid, recover silicon powder, avoid causing resource waste, save cost, improve practicality.

[0030] The top center of the movable plate 201 is fixedly installed with a stirring motor 207, and the output end of the stirring motor 207 penetrates through the movable plate 201 and is fixedly installed with a stirring shaft 208, and the outside of the stirring shaft 208 is symmetrically installed with a plurality of stirring rods 209, which can stir the waste cutting fluid. The bottom of the movable plate 201 is fixedly installed with an ultrasonic vibration rod 210 on one side of the stirring shaft 208. The specific model of the ultrasonic vibration rod 210 is ZB2000, which is a prior art. The ultrasonic vibration rod 210 can be inserted into the waste cutting fluid. The top side of the movable plate 201 is fixedly installed with a liquid storage tank 211, and a liquid outlet pipe 212 is penetratingly arranged on the side of the liquid storage tank 211, and the liquid outlet pipe 212 is connected with the movable plate 201, and an electromagnetic valve is arranged on the outside of the liquid outlet pipe 212, which is convenient for adjusting the calcium chloride medicament dosage. The positioning assembly 3 comprises positioning plates 301 symmetrically arranged inside the positioning frame 103, and limit rods 302 are symmetrically installed on the sides away from the two positioning plates 301, and the limit rods 302 are slidingly connected with the positioning frame 103, and a reset spring 3021 is sleeved on the outside of the limit rod 302, one end of the reset spring 3021 is fixedly connected with the positioning frame 103, and the other end of the reset spring 3021 is fixedly connected with the limit rod 302, and the top of the two positioning plates 301 is fixedly installed with a vertical rod 303, and the vertical rod 303 is fixedly installed with a guide rod 305 on one side, and the guide rod 305 is slidingly connected with a mounting bracket 304 on the outside of one side, and the mounting bracket 304 is fixedly connected with the positioning frame 103, which is convenient for the user to fix the tank and avoid displacement of the tank in subsequent production operation.

[0031] The top of the two vertical rods 303 is hingedly connected with a rotating rod 306, and a torsional spring 307 is arranged at the connection between the rotating rod 306 and the vertical rod 303, and a column block 3061 is fixedly installed on the side of the rotating rod 306, so that the rotating rod 306 can always be inclined under the action of the torsional spring 307. The bottom of the movable plate 201 is symmetrically installed with two groups of fixed blocks 308 on both sides, and a fixed rod 309 is fixedly installed between every two fixed blocks 308, and an active block 310 is slidingly connected with the outside of the fixed rod 309, and a telescopic spring 311 is sleeved on the outside of the fixed rod 309, one end of the telescopic spring 311 is fixedly connected with one side of the fixed block 308, and the other end of the telescopic spring 311 is fixedly connected with the active block 310, and a fixed seat 312 is fixedly installed on the bottom of the active block 310, and the column block 3061 is adaptively connected with the fixed seat 312, so that the descent of the movable plate 201 can drive the positioning plate 301 to move.

[0032] Working principle: Before using the equipment for recovering silicon powder from semiconductor silicon wafer processing cutting fluid, the overall condition of the device needs to be checked to determine whether it can work normally. According to the actual situation, the waste cutting fluid is poured into the tank, and the ultrasonic vibration rod 210 is inserted into the waste cutting fluid. The waste cutting fluid is stirred by the stirring motor 207 and the stirring rods 209, and the waste cutting fluid is treated by the ultrasonic vibration rod 210. The waste cutting fluid is treated by the ultrasonic vibration rod 210. Figure 1 -Figure 5 As shown, when the cutting liquid is recycled, the waste cutting liquid in the square box is transferred to the upper part of the workbench 1 by the forklift, the rear side of the square box is attached to the positioning frame 103, then the driving motor 203 is started to drive the threaded rod 202 to rotate, the threaded rod 202 rotates to drive the threaded sleeve 204 to move, so that the movable plate 201 descends, the movable sleeve 205 slides on the support rod 206 during the movement to limit the movement, so that the stirring shaft 208 is inserted into the square box, and the ultrasonic vibration rod 210 is inserted into the square box; the calcium chloride solution is stored in the liquid storage tank 211, and the amount of calcium chloride added into the square box is controlled by the electromagnetic valve on the liquid outlet pipe 212; the stirring motor 207 drives the stirring rod 209 to rotate to stir the cutting liquid, so that the waste cutting liquid is fully homogenized, and the reaction rate is improved. By adding a certain proportion of calcium chloride to the reaction system, the calcium chloride dissociates into positive and negative ions when it is added to the system, and strong hydration occurs, that is, water is competed for, so that the free water molecules in the liquid are reduced, and the system is dehydrated, thereby destroying the stable phase structure of the molecules. After adding calcium chloride to the cutting liquid containing a surfactant, Ca 2+ The double electric layer is compressed, the zeta potential is reduced, the mutual repulsion between silicon molecules is reduced, the molecular stability is destroyed, and the stable state is lost. Under the action of van der Waals force, it is possible to collide and become dispersed and then have sedimentation.

[0033] At the same time, the ultrasonic generator 104 and the ultrasonic vibration rod 210 are started, the strong cavitation effect, disturbance effect, high acceleration, crushing and stirring effect and other multi-level effects generated by ultrasonic radiation pressure are utilized, the movement frequency and speed of the substance molecules in the waste cutting liquid are increased, the solvent penetration is increased, thereby accelerating the separation of the silicon powder and the solvent, and promoting the unstable settling of the silicon powder. After ultrasonic completion, the waste cutting liquid square box separated is transferred from the workbench 1, and is left to separate, the upper waste water enters the sewage station for treatment, and the silicon powder is recycled. After the silicon wafer is cut, the silicon powder in the cutting liquid can be effectively separated, the silicon powder is recycled, the problems of high difficulty in separating the waste cutting liquid silicon powder, high disposal cost and resource waste are solved. The device is simple to operate, and the practicality is improved;

[0034] When positioning the square box, the rear side of the square box is attached to the positioning frame 103, then the movable plate 201 is lowered to drive the fixed seat 312 to be lowered, the fixed seat 312 is clamped outside the column block 3061, then the movable plate 201 continues to be lowered to push the rotating rod 306 to rotate, the rotating rod 306 rotates to push the positioning plate 301 to move through the vertical rod 303, so that the limiting rod 302 slides on the positioning frame 103 and compresses the return spring 3021, so that the two positioning plates 301 are attached to the two sides of the square box, then the movable plate 201 continues to be lowered to make the movable block 310 slide on the fixed rod 309, and the extension spring 311 can be stretched, so that the movable plate 201 can also be moved after positioning the square box, through the positioning assembly 3, the user can conveniently fix the square box, and displacement of the square box in actual production is avoided.

[0035] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacement to part of the technical features, and any modification, equivalent replacement, improvement, etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. An apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid, comprising a worktable (1); The bottom of the workbench (1) is symmetrically equipped with two sets of support legs (101), and the top of the workbench (1) is fixedly equipped with a fixed frame (102), and a controller is provided on one side of the bottom of the workbench (1). Its features are, Also includes: The top of the workbench (1) is fixedly installed with a positioning frame (103) below the fixed frame (102), and an ultrasonic generator (104) is fixedly installed at the bottom center of the workbench (1). A separation and recycling component (2) is provided below the fixed frame (102), and a positioning component (3) is provided inside and above the positioning frame (103). The separation and recycling component (2) includes a movable plate (201) disposed above the inside of the fixed frame (102), and a threaded sleeve (204) is fixedly installed on one side of the movable plate (201), and a threaded rod (202) is threadedly connected inside the threaded sleeve (204), and the two ends of the threaded rod (202) are rotatably connected to the fixed frame (102) and the worktable (1) respectively. Among them, a drive motor (203) is fixedly installed on one side of the top of the fixed frame (102), and the output end of the drive motor (203) passes through the fixed frame (102) and is fixedly connected to the threaded rod (202). On the other side of the movable plate (201), movable sleeves (205) are symmetrically installed. Support rods (206) are slidably connected inside the two movable sleeves (205), and the two ends of the two support rods (206) are fixedly connected to the fixed frame (102) and the worktable (1) respectively.

2. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 1, characterized in that: A stirring motor (207) is fixedly installed at the top center of the movable plate (201), and the output end of the stirring motor (207) passes through the movable plate (201) and is fixedly installed with a stirring shaft (208), and several stirring rods (209) are symmetrically installed on the outside of the stirring shaft (208).

3. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 2, characterized in that: An ultrasonic vibrating rod (210) is fixedly installed on the bottom of the movable plate (201) on one side of the stirring shaft (208).

4. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 1, characterized in that: A liquid storage tank (211) is fixedly installed on one side of the top of the movable plate (201), and a liquid outlet pipe (212) is provided through the lower side of one side of the liquid storage tank (211). The liquid outlet pipe (212) is connected through the movable plate (201), and an electromagnetic valve is provided on the lower outside of the liquid outlet pipe (212).

5. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 1, characterized in that: The positioning component (3) includes positioning plates (301) symmetrically arranged inside the positioning frame (103), and limiting rods (302) are symmetrically installed on the opposite sides of the two positioning plates (301). The limiting rods (302) are slidably connected to the positioning frame (103). A return spring (3021) is sleeved on the outer side of the limiting rod (302). One end of the return spring (3021) is fixedly connected to the positioning frame (103), and the other end of the return spring (3021) is fixedly connected to the limiting rod (302). A vertical rod (303) is fixedly installed on the top of the two positioning plates (301). A guide rod (305) is fixedly installed on one side of the vertical rod (303). A mounting frame (304) is slidably connected to the outer side of the guide rod (305). The mounting frame (304) is fixedly connected to the positioning frame (103).

6. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 5, characterized in that: The top of each of the two uprights (303) is hinged with a rotating rod (306), and a torsion spring (307) is provided at the connection between the rotating rod (306) and the upright (303). A column block (3061) is fixedly installed on one side above the rotating rod (306).

7. The apparatus for recovering silicon powder from semiconductor silicon wafer cutting fluid according to claim 6, characterized in that: Two sets of fixing blocks (308) are symmetrically installed on both sides of the bottom of the movable plate (201), and a fixing rod (309) is fixedly installed between the two fixing blocks (308) in each set. A movable block (310) is slidably connected to the outside of the fixing rod (309). A telescopic spring (311) is sleeved on one side of the fixing rod (309). One end of the telescopic spring (311) is fixedly connected to one side of the fixing block (308), and the other end of the telescopic spring (311) is fixedly connected to the movable block (310). A fixing seat (312) is fixedly installed at the bottom of the movable block (310), and the column block (3061) is adapted to the fixing seat (312).

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