A liquid cleaning device for preventing silicon wafer oxidation

Abstract

The application discloses a liquid cleaning device for preventing silicon wafer oxidation, which comprises an operation main body, the operation main body comprises a base, the base is rotationally connected with a rotating shaft through a support arranged on the top of the base, and the rotating shaft is fixedly connected with an ultrasonic cleaning box on the circumferential outer surface; the ultrasonic cleaning box is internally provided with a placing part, the placing part comprises a supporting block, the bottom of the supporting block is fixedly connected with the inner wall bottom of the ultrasonic cleaning box, the top of the supporting block is fixedly connected with a supporting plate, the top of the supporting plate is fixedly connected with a frame plate, and a load object for placing external silicon wafers is arranged between the adjacent surfaces of the frame plate. The ultrasonic cleaning box and the placing part are arranged, the ultrasonic cleaning box is intermittently swung left and right, the lower surface of the silicon wafer is intermittently and alternately contacted with the second load plate and the first load plate, the lower surface of the silicon wafer can be fully cleaned, the trouble of turning over the silicon wafer by 180 degrees for secondary cleaning is saved, the cleaning time is saved, the cleaning efficiency is high, and the automatic production is facilitated.

Description

Technical Field

[0001] This invention relates to the field of silicon wafer cleaning technology, and more specifically to a chemical cleaning device for preventing silicon wafer oxidation. Background Technology

[0002] After photovoltaic silicon wafers undergo various processing steps such as slicing, chamfering, double-sided grinding, and polishing, their surfaces become heavily contaminated. To prevent further oxidation, the outer surface of the silicon wafer needs to be cleaned with a chemical solution to remove contaminants. Contaminants typically exist on the silicon wafer surface in the form of atoms, ions, molecules, particles, or films, through physical or chemical adsorption. Ultrasonic cleaning machines utilize the cavitation, acceleration, and flow effects of ultrasound in liquids to directly and indirectly act on the liquid and contaminants, dispersing, emulsifying, and peeling off the contaminant layer to achieve the cleaning purpose.

[0003] Existing ultrasonic cleaning equipment is a physical cleaning method. First, the silicon wafer is placed in the cleaning tank, then the ultrasonic cleaning solution is added. During propagation, the pressure of the medium changes alternately, generating tearing forces in the negative pressure area of ​​the liquid and forming extremely tiny vacuum bubbles. These bubbles rapidly collapse, producing minute scrubbing motions that remove the contaminant layer. Since both sides of the silicon wafer need to be cleaned, there is a contact surface between the wafer and the rack in the cleaning tank. This contact surface cannot be cleaned by the ultrasonic waves, requiring the wafer to be manually rotated 180 degrees for a second cleaning. Overall, the cleaning efficiency is low, which is not conducive to automated production. Summary of the Invention

[0004] Technical problems to be solved

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a chemical cleaning device for preventing silicon wafer oxidation. This device effectively solves the problem that existing ultrasonic cleaning equipment is a physical cleaning method. First, the silicon wafer is placed in the cleaning tank, and then the ultrasonic cleaning solution is added. Since both sides of the silicon wafer need to be cleaned, there is a contact surface between the wafer and the rack in the cleaning tank. This contact surface cannot be cleaned by the ultrasonic waves, requiring the wafer to be manually rotated 180 degrees for a second cleaning. This results in low overall cleaning efficiency and is not conducive to automated production.

[0006] Technical solution

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] The present invention provides a chemical cleaning device for preventing silicon wafer oxidation, comprising an operating body, the operating body including a base, the base being rotatably connected to a rotating shaft via a bracket disposed on its top, and an ultrasonic cleaning chamber being fixedly connected to the outer circumference of the rotating shaft;

[0009] The ultrasonic cleaning chamber is provided with a placement section, which includes a support block. The bottom of the support block is fixedly connected to the bottom of the inner wall of the ultrasonic cleaning chamber. A support plate is fixedly connected to the top of the support block. A frame plate is fixedly connected to the top of the support plate. A carrier for placing external silicon wafers is provided between adjacent surfaces of a pair of frame plates.

[0010] Furthermore, the top of the ultrasonic cleaning box is rotatably connected to a viewing window via a damper hinge, and the top of the base is fixedly connected to a lifting seat that is connected to the bottom of the ultrasonic cleaning box.

[0011] Furthermore, the loading component includes a first loading plate and a second loading plate, which are staggered from left to right. The end face of the first loading plate is fixedly connected to the side of the frame plate. A lifting groove is formed on the lower surface of the frame plate that fits against the outer surface of the second loading plate. A lifting rod is fixedly connected to the top of the second loading plate, and the top end of the lifting rod passes through the lifting groove and is slidably connected to the inside of the frame plate.

[0012] Furthermore, both the first and second carrier plates have water-permeable holes inside, and triangular plates are fixedly connected to the lower surfaces of both the first and second carrier plates, with an arc-shaped rod fixedly connected to the bottom of the triangular plates.

[0013] Furthermore, a ramp block is fixedly connected to the side of the frame plate away from the first load plate. The ramp block is slidably connected to a reciprocating block through a sliding hole opened inside it, and the lower surface of the reciprocating block is in contact with the inclined surface of the ramp block.

[0014] Furthermore, a piston plate is slidably connected to the inner wall of the ultrasonic cleaning chamber, and a push rod is fixedly connected between adjacent surfaces of a pair of piston plates. A limiting rod that slides with the interior of the ultrasonic cleaning chamber is fixedly connected to the side of the piston plate away from the push rod, and a push plate that slides with the interior of the reciprocating block is fixedly connected to the outer circumference of the limiting rod.

[0015] Furthermore, the reciprocating block has an opening slot on the side near the frame plate, and the end face of the second carrier plate is fixedly connected to a smooth rod that slides against the inner wall of the opening slot via a connecting rod.

[0016] Beneficial effects

[0017] The technical solution provided by this invention has the following advantages compared with the prior art:

[0018] This invention is equipped with an ultrasonic cleaning box and a placement part, which allows the ultrasonic cleaning box to swing intermittently from left to right, so that the lower surface of the silicon wafer alternately contacts the second carrier plate and the first carrier plate, thereby enabling thorough cleaning of the lower surface of the silicon wafer. This eliminates the trouble of flipping the silicon wafer 180 degrees for secondary cleaning, greatly reduces the cleaning time of the silicon wafer, has high cleaning efficiency, and is conducive to automated production. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0020] Figure 1 This is a three-dimensional structural schematic diagram of an embodiment of the present invention;

[0021] Figure 2 This is a three-dimensional structural diagram of the ultrasonic cleaning box and placement part according to an embodiment of the present invention;

[0022] Figure 3 This is a three-dimensional structural schematic diagram of the placement part according to an embodiment of the present invention;

[0023] Figure 4 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of part A in the middle;

[0024] Figure 5 This is a schematic diagram of the three-dimensional separation of the smooth rod, reciprocating block, and push plate in an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of a three-dimensional portion of the object in an embodiment of the present invention.

[0026] The labels in the diagram represent: 1. Operating body; 11. Base; 12. Support; 13. Rotating shaft; 14. Ultrasonic cleaning box; 141. Piston plate; 142. Push rod; 143. Limiting rod; 144. Push plate; 15. Viewing window; 16. Lifting seat; 2. Placement part; 21. Support block; 22. Support plate; 23. Frame plate; 231. Lifting groove; 232. Inclined block; 233. Sliding hole; 234. Reciprocating block; 2341. Opening groove; 24. Loading component; 241. First loading plate; 242. Second loading plate; 2421. Smooth rod; 243. Lifting rod; 244. Water permeable hole; 245. Triangular plate; 246. Arc rod. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] The present invention will be further described below with reference to embodiments.

[0029] Example:

[0030] Please see Figures 1-6 The present invention provides a technical solution: a chemical cleaning device for preventing silicon wafer oxidation, including an operating body 1, the operating body 1 including a base 11, the base 11 being rotatably connected to a rotating shaft 13 via a bracket 12 set on its top, and an ultrasonic cleaning box 14 being fixedly connected to the outer circumference of the rotating shaft 13.

[0031] The ultrasonic cleaning chamber 14 is provided with a placement part 2, which includes a support block 21. The bottom of the support block 21 is fixedly connected to the bottom of the inner wall of the ultrasonic cleaning chamber 14. A support plate 22 is fixedly connected to the top of the support block 21. A frame plate 23 is fixedly connected to the top of the support plate 22. A carrier 24 for placing external silicon wafers is provided between the adjacent surfaces of a pair of frame plates 23.

[0032] The top of the ultrasonic cleaning box 14 is rotatably connected to a viewing window 15 via a damper hinge, and the top of the base 11 is fixedly connected to a lifting seat 16 that is connected to the bottom of the ultrasonic cleaning box 14.

[0033] The loading component 24 includes a first loading plate 241 and a second loading plate 242, which are staggered from left to right. The end face of the first loading plate 241 is fixedly connected to the side of the frame plate 23. The lower surface of the frame plate 23 is provided with a lifting groove 231 that fits against the outer surface of the second loading plate 242. The top of the second loading plate 242 is fixedly connected with a lifting rod 243, and the top end of the lifting rod 243 passes through the lifting groove 231 and is slidably connected to the inside of the frame plate 23.

[0034] Both the first carrier plate 241 and the second carrier plate 242 have water-permeable holes 244 inside, which increases the contact area between the lower surface of the silicon wafer and the cleaning solution. At the same time, it facilitates the rapid removal of contaminants from the silicon wafer and their dissolution in the solution. During the intermittent small-angle oscillation of the ultrasonic cleaning box 14, the flow of the solution through the water-permeable holes 244 is conducive to the removal of contaminants. Triangular plates 245 are fixedly connected to the lower surface of both the first carrier plate 241 and the second carrier plate 242. An arc-shaped rod 246 is fixedly connected to the bottom of the triangular plate 245. With the cooperation of the triangular plate 245 and the arc-shaped rod 246, the contaminants in the water-permeable holes 244 are quickly dissolved in the solution. At the same time, the arc-shaped rod 246 acts as a "reinforcing rib", further improving the stability of the first carrier plate 241 and the second carrier plate 242.

[0035] A ramp block 232 is fixedly connected to the side of the frame plate 23 away from the first load plate 241. The ramp block 232 is slidably connected to a reciprocating block 234 through a sliding hole 233 opened inside it, and the lower surface of the reciprocating block 234 is in contact with the inclined surface of the ramp block 232.

[0036] A piston plate 141 is slidably connected to the inner wall of the ultrasonic cleaning chamber 14. A push rod 142 is fixedly connected between adjacent surfaces of a pair of piston plates 141. A limiting rod 143 that slides with the interior of the ultrasonic cleaning chamber 14 is fixedly connected to the side of the piston plate 141 away from the push rod 142. A push plate 144 that slides with the interior of the reciprocating block 234 is fixedly connected to the outer circumference of the limiting rod 143.

[0037] The reciprocating block 234 has an opening slot 2341 on the side near the frame plate 23, and the end face of the second carrier plate 242 is fixedly connected to a smooth rod 2421 that slides against the inner wall of the opening slot 2341 via a connecting rod.

[0038] refer to Figure 1-6 Existing ultrasonic cleaning equipment is a physical cleaning method. First, the silicon wafer is placed in the cleaning tank, then the ultrasonic cleaning solution is added. During the propagation of the ultrasonic waves, the pressure of the medium alternates, generating tearing forces in the negative pressure area of ​​the liquid and forming extremely tiny vacuum bubbles. These bubbles rapidly collapse, producing minute scrubbing motions that remove the contaminant layer. Since both sides of the silicon wafer need to be cleaned, there is a contact surface between the wafer and the rack in the cleaning tank. This contact surface cannot be cleaned by the ultrasonic waves, requiring the wafer to be manually rotated 180 degrees for a second cleaning. Overall, the cleaning efficiency is low, which is not conducive to automated production.

[0039] To overcome the aforementioned defects, this invention designs a chemical cleaning device to prevent silicon wafer oxidation.

[0040] Silicon wafer placement:

[0041] Initially, the output end of the lifting seat 16 drives the ultrasonic cleaning box 14 to tilt to the left at a small angle. The ultrasonic cleaning box 14 rotates around the inside of the bracket 12 by means of the rotating shaft 13. Then, the silicon wafer to be cleaned is placed on the upper surface of the carrier 24. At the same time, protective plates are detachably installed on both sides of the frame plate 23. The silicon wafer is located in the space enclosed by the protective plate and the frame plate 23. After the silicon wafer is placed, ultrasonic cleaning solution is introduced into the ultrasonic cleaning chamber 14. Due to the slight leftward tilt of the ultrasonic cleaning chamber 14, the solution is affected by gravity and mainly gathers to the left (but the horizontal level of the solution always covers the upper surface of the silicon wafer). The gravity of the solution pushes the piston plate 141 to slide a short distance to the left, causing the limiting rod 143 to slide along the inside of the ultrasonic cleaning chamber 14 (the limiting rod 143 not only limits the sliding distance of the piston plate 141, but also ensures that the piston plate 141 slides smoothly). This causes the push rod 142 to slide a short distance to the left in sync, and causes the push plate 144 and the reciprocating block 234 to slide a short distance to the left in sync. The lower surface of the reciprocating block 234 slides along the inclined surface of the ramp block 232 (the reciprocating block 234 slides a short distance to the left on one side and a short distance downward on the other side, and relative sliding occurs between the reciprocating block 234 and the push plate 144). Meanwhile, the opening slot 2341 on the reciprocating block 234 slides along the outer circumference of the smooth rod 2421. The end face of the second carrier plate 242 is fixed to the smooth rod 2421 by the connecting rod. The second carrier plate 242, the lifting rod 243 and the smooth rod 2421 are combined into a whole. The reciprocating block 234 slides to the left and down simultaneously, causing the second carrier plate 242, the lifting rod 243 and the smooth rod 2421 to slide down simultaneously until the reciprocating block 234 slides to the leftmost side of the ramp block 232. At this time, the second carrier plate 242 is located below the first carrier plate 241. The lower surface of the silicon wafer is in contact with the upper surface of the first carrier plate 241, and the lower surface of the silicon wafer is not in contact with the upper surface of the second carrier plate 242.

[0042] Silicon wafer tilted to the left for cleaning:

[0043] As described above, when the ultrasonic cleaning chamber 14 is tilted to the left at a small angle, the silicon wafer adheres to the upper surface of the first carrier plate 241 (the lower surface of the silicon wafer does not contact the upper surface of the second carrier plate 242). Then, the ultrasonic generator inside the ultrasonic cleaning chamber 14 is activated. The principle is that under the action of strong ultrasonic waves, sparse and dense parts are generated inside the liquid. The sparse parts generate near-vacuum cavities. When the cavities disappear, strong local pressure is generated nearby, causing the chemical bonds in the molecules to break. Thus, the impurities on the surface of the silicon wafer are decomposed. The high-pressure and high-temperature shock wave generated by the bursting of the bubbles reduces the adhesion between the dirt and the cleaned object, causing the dirt to be destroyed. At the same time, the vibration of the bubbles can perform friction cleaning on the surface of the cleaned object. The bubbles can also penetrate into the cracks and vibrate, causing the mist layer to fall off. When oil adheres to certain solid surfaces, the oil is emulsified by ultrasound and quickly detaches from the surface of the part being cleaned. Ultrasonic cavitation generates a high velocity gradient and upflow on the surface of the part being cleaned, which can further weaken or remove boundary layer contamination. At the same time, ultrasonic vibration also causes strong vibration of the medium particles, which causes the surface of the part being cleaned to be subjected to strong impact, causing the contaminants to quickly detach from the surface.

[0044] Tilting the silicon wafer to the right for cleaning (primary purpose: to switch the contact surface of the lower surface of the silicon wafer):

[0045] The first carrier plate 241 and the second carrier plate 242 are staggered from left to right. When the ultrasonic cleaning box 14 is tilted to the left at a small angle, the first carrier plate 241 is in contact with the lower surface of the silicon wafer (this contact surface cannot be cleaned by ultrasonic waves). At this time, the ultrasonic cleaning box 14 is adjusted to tilt to the right at a small angle, and the second carrier plate 242 is in contact with the lower surface of the silicon wafer. The previously uncleaned contact surface will then be cleaned by ultrasonic waves. By intermittently repeating the above operation, even if the ultrasonic cleaning box 14 swings intermittently from left to right, the lower surface of the silicon wafer is intermittently in contact with the second carrier plate 242 and the first carrier plate 241, so that the lower surface of the silicon wafer can be cleaned well. This eliminates the trouble of flipping the silicon wafer 180 degrees for secondary cleaning, greatly reduces the cleaning time of the silicon wafer, has high cleaning efficiency, and is conducive to automated production (due to the cavitation effect of ultrasonic waves, prolonged cleaning can damage the silicon wafer).

[0046] Specifically, the output end of the lifting seat 16 causes the ultrasonic cleaning box 14 to tilt to the right at a small angle. Due to the influence of gravity, the ultrasonic cleaning solution mainly gathers to the right. The gravity of the solution pushes the piston plate 141 to slide to the right a short distance, causing the limit rod 143 to slide along the inside of the ultrasonic cleaning box 14, causing the push rod 142 to slide to the right a short distance simultaneously, causing the push plate 144 and the reciprocating block 234 to slide to the right a short distance simultaneously. The lower surface of the reciprocating block 234 slides to the upper right along the slope of the ramp block 232 (the reciprocating block 234 slides to the right a short distance on one side and upwards a short distance on the other side, and the push plate 144 partially slides out of the reciprocating block 234). Meanwhile, the opening slot 2341 on the reciprocating block 234 slides along the outer circumferential surface of the smooth rod 2421. The reciprocating block 234 slides short distance to the right and short distance upward at the same time, causing the second carrier plate 242, the lifting rod 243 and the smooth rod 2421 to slide short distance upward synchronously until the reciprocating block 234 slides to the rightmost side of the ramp block 232. At this time, the second carrier plate 242 passes over the first carrier plate 241 and is above it. The lower surface of the silicon wafer does not contact the upper surface of the first carrier plate 241, and the lower surface of the silicon wafer is in contact with the upper surface of the second carrier plate 242. Then the liquid will clean the previously contacted surfaces.

[0047] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A chemical cleaning device for preventing silicon wafer oxidation, characterized in that, include: The operating body (1) includes a base (11), and the base (11) is rotatably connected to a rotating shaft (13) via a bracket (12) set on its top. An ultrasonic cleaning box (14) is fixedly connected to the outer circumference of the rotating shaft (13). Placement section (2), the placement section (2) includes a support block (21), the bottom of the support block (21) is fixedly connected to the bottom of the inner wall of the ultrasonic cleaning box (14), the top of the support block (21) is fixedly connected to a support plate (22), the top of the support plate (22) is fixedly connected to a frame plate (23), and a carrier (24) for placing external silicon wafers is provided between adjacent surfaces of a pair of frame plates (23). The top of the ultrasonic cleaning box (14) is rotatably connected to a viewing window (15) via a damper hinge, and the top of the base (11) is fixedly connected to a lifting seat (16) connected to the bottom of the ultrasonic cleaning box (14). The loading component (24) includes a first loading plate (241) and a second loading plate (242). The first loading plate (241) and the second loading plate (242) are staggered from left to right. The end face of the first loading plate (241) is fixedly connected to the side of the frame plate (23). The lower surface of the frame plate (23) is provided with a lifting groove (231) that fits against the outer surface of the second loading plate (242). The top of the second loading plate (242) is fixedly connected with a lifting rod (243), and the top end of the lifting rod (243) passes through the lifting groove (231) and is slidably connected to the inside of the frame plate (23). Both the first loading plate (241) and the second loading plate (242) have water-permeable holes (244) inside. Both the first loading plate (241) and the second loading plate (242) have triangular plates (245) fixedly connected to their lower surfaces. The bottom of the triangular plates (245) has an arc-shaped rod (246) fixedly connected to them.

2. The chemical cleaning device for preventing silicon wafer oxidation according to claim 1, characterized in that: The frame plate (23) is fixedly connected to a ramp block (232) on the side away from the first load plate (241). The ramp block (232) is slidably connected to a reciprocating block (234) through a sliding hole (233) opened inside it, and the lower surface of the reciprocating block (234) is in contact with the inclined surface of the ramp block (232).

3. The chemical cleaning device for preventing silicon wafer oxidation according to claim 2, characterized in that: A piston plate (141) is slidably connected to the inner wall of the ultrasonic cleaning box (14). A push rod (142) is fixedly connected between adjacent surfaces of a pair of piston plates (141). A limiting rod (143) that slides with the inside of the ultrasonic cleaning box (14) is fixedly connected to the side of the piston plate (141) away from the push rod (142). A push plate (144) that slides with the inside of the reciprocating block (234) is fixedly connected to the outer circumference of the limiting rod (143).

4. The chemical cleaning device for preventing silicon wafer oxidation according to claim 2, characterized in that: The reciprocating block (234) has an opening slot (2341) on the side near the frame plate (23), and the end face of the second carrier plate (242) is fixedly connected to a smooth rod (2421) that slides against the inner wall of the opening slot (2341) by a connecting rod.

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