Wafer wet etching device

Abstract

The utility model discloses a wafer wet etching device which comprises an etching groove, a liquid storage bin is fixedly installed at the bottom of the etching groove, a working table is installed on the upper surface of a bottom plate of the etching groove in a sliding mode, a wafer rotating chuck is horizontally and rotatably installed on the working table, and a through liquid outlet is formed in the position, corresponding to a through hole, of the working table. An anti-corrosion pump is arranged outside one side of the liquid storage bin, the input end of the anti-corrosion pump is fixedly connected with a liquid inlet pipe, the output end of the anti-corrosion pump is fixedly connected with a liquid discharging pipe, supporting blocks are arranged at the positions, close to the top, of the inner periphery of the etching tank, a spraying bin is fixedly installed on the supporting blocks, and a plurality of nozzles are arranged on the lower surface of the spraying bin and distributed in a circumferential mode; the end, away from the anti-corrosion pump, of the liquid discharging pipe penetrates through the side wall of the etching groove and communicates with the spraying bin. A plurality of nozzles are arranged on the spraying bin, and a plurality of layers of nozzles and the wafer rotating chuck are concentrically and circumferentially distributed, so that a solution sprayed by the nozzles can be uniformly distributed on the surface of a wafer, and the uniformity of wafer etching is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of etching, in particular to a wafer wet etching device. Background Art

[0002] The chemical reaction of wet etching belongs to the reaction between liquid phase and solid phase. When wet etching is in progress, first, the reactants in the solution will use the diffusion effect to pass through a very thin boundary layer to reach the surface of the etched film. Then, these reactants will react chemically with the molecules on the surface of the film to generate various products. These products on the surface of the film will also use the diffusion effect to pass through the boundary layer into the solution, and then be discharged with the solution.

[0003] During the existing wet etching process, the wafer is in a high-speed rotating state, and the chemical solution is sprayed to the center of the wafer. The centrifugal force of the rotation then causes the solution to flow from the center of the wafer to the edge. However, the centrifugal force at the edge of the wafer is the greatest, causing the solution to stay at the edge of the wafer for a short time, resulting in an etching rate in the center that is higher than that at the edge, resulting in poor uniformity of the entire wafer, making the final wafer product unevenly etched. Utility Model Content

[0004] The utility model aims to provide a wafer wet etching device, which can evenly spray the solution onto the surface of the wafer, effectively solving the problem that the solution is sprayed onto the center of the wafer and flows to the edge by centrifugal force, causing the solution to stay at the edge of the wafer for a short time, resulting in an etching rate in the center higher than that at the edge, resulting in poor uniformity of the entire wafer.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a wafer wet etching device, comprising an etching tank, a liquid storage tank is fixedly installed at the bottom of the etching tank, a through hole is opened on one side of the bottom plate of the etching tank, the etching tank is connected with the liquid storage tank through the through hole, a workbench is slidably installed on the upper surface of the bottom plate of the etching tank, a wafer rotating chuck is horizontally rotatably installed on the workbench, a cavity is arranged in the workbench, the bottom of the wafer rotating chuck extends downward into the cavity, a driving mechanism for driving the wafer rotating chuck to rotate back and forth is arranged in the cavity, and a through hole is opened at the position of the workbench corresponding to the through hole. A through discharge port, a heating pipe is fixedly installed at the bottom of the liquid storage bin, an anti-corrosion pump is arranged on the outside of one side of the liquid storage bin, the input end of the anti-corrosion pump is fixedly connected with a liquid inlet pipe, the end of the liquid inlet pipe away from the anti-corrosion pump passes through the side wall of the liquid storage bin and extends to the interior of the liquid storage bin, the output end of the anti-corrosion pump is fixedly connected with a discharge pipe, support blocks are arranged around the etching tank near the top, a spray bin is fixedly installed on the support block, a plurality of nozzles are arranged on the lower surface of the spray bin, the nozzles are distributed in a circle, the end of the discharge pipe away from the anti-corrosion pump passes through the side wall of the etching tank and is connected with the spray bin.

[0006] The wafer rotation chuck is used to install the wafer, the driving mechanism is used to drive the wafer rotation chuck to rotate back and forth, the anti-corrosion pump is used to transport the solution in the liquid storage tank through the liquid inlet pipe and the liquid discharge pipe to the spraying tank, and then spray it onto the wafer through the nozzle at the lower end of the spraying tank for etching. After etching, the solution flowing down from the wafer flows into the liquid storage tank through the drain port on the workbench and the through hole at the bottom of the etching tank. The heating pipe in the liquid storage tank is also used to heat the solution. Since the nozzles are distributed in a circle, the solution can be evenly sprayed onto the wafer surface, so that the etching rate of the wafer surface is consistent, thereby improving the uniformity of the entire wafer.

[0007] Preferably, a sealing portion is provided at one end of the workbench away from the drain port, a downwardly inclined inclined portion is provided on the side of the sealing portion facing the drain port, the lower end of the inclined portion extends between the wafer rotating chuck and the drain port, and the wafer rotating chuck and the inclined portion are sealed and rotatably connected. Providing the inclined portion can facilitate the solution to flow to the drain port and avoid solution residue on the surface of the workbench.

[0008] Preferably, the sealing part extends through the side wall of the corresponding etching groove to the outside of the etching groove, and the sealing part is slidably connected to the side wall of the etching groove. The workbench and the etching groove are arranged to be slidably connected, and the sealing part and the side wall of the etching groove are arranged to be slidably connected so that the workbench can be pulled out of the etching groove, which is convenient for mounting the wafer on the wafer rotating chuck, and the sealing part is arranged to seal the gap between the etching groove and the workbench to prevent the solution from leaking out.

[0009] Preferably, the driving mechanism comprises an electric telescopic rod, a rack and a gear matching the rack, the gear is fixedly mounted on the bottom of the wafer rotating chuck, the bottom of the gear is rotatably connected to the workbench, the electric telescopic rod is fixedly mounted on the side of the cavity away from the gear, one end of the rack is fixedly connected to the output end of the electric telescopic rod, and the other end is meshed with the gear. The rack is driven to move back and forth by the telescopic movement of the electric telescopic rod, thereby driving the gear to rotate back and forth, so that the wafer rotating chuck can rotate back and forth.

[0010] Preferably, one end of the liquid inlet pipe located in the liquid storage bin is fixedly connected with a filter, which is used to filter impurities in the solution to improve etching quality.

[0011] Preferably, the nozzle is provided with multiple layers from the outside to the inside, and is concentric with the wafer rotating chuck, and the outermost layer of the nozzle faces the edge of the wafer rotating chuck, thereby increasing the amount of solution sprayed and ensuring that the solution sprayed from the nozzle can be evenly distributed on the wafer surface, thereby improving the etching quality and etching rate.

[0012] Compared with the prior art, the utility model adopts the above technical solution and has the following technical effects:

[0013] The utility model arranges multiple nozzles on a spray bin, and has multiple layers distributed on the same center and circumference as the wafer rotating chuck, so that the solution sprayed from the nozzles can be evenly distributed on the wafer surface, and then the wafer rotating chuck is driven to rotate back and forth by a driving mechanism, so that the solution flow at the edge of the wafer is not less than that at the center of the wafer, thereby avoiding the problem that the solution is sprayed to the center of the wafer and then flows to the edge through centrifugal force, causing the solution to stay at the edge of the wafer for a short time, resulting in an etching rate in the center being higher than that at the edge, resulting in poor uniformity of the entire wafer, thereby improving the etching uniformity of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a front cross-sectional schematic diagram of the utility model;

[0015] Figure 2 It is a structural schematic diagram of the workbench of the utility model;

[0016] Figure 3 It is a bottom view schematic diagram of the spraying bin of the utility model.

[0017] Explanation of the reference numerals in the accompanying drawings: 1. Etching groove; 2. Liquid storage tank; 3. Through hole; 4. Workbench; 5. Wafer rotation chuck; 6. Cavity; 7. Driving mechanism; 8. Drain port; 9. Heating pipe; 10. Anti-corrosion pump; 11. Liquid inlet pipe; 12. Drain pipe; 13. Support block; 14. Spraying tank; 15. Nozzle; 16. Sealing part; 17. Inclined part; 18. Electric telescopic rod; 19. Rack; 20. Gear; 21. Filter. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.

[0020] See also Figure 1-3The utility model provides a technical solution: it includes an etching tank 1, a liquid storage tank 2 is fixedly installed at the bottom of the etching tank 1, a through hole 3 is opened on one side of the bottom plate of the etching tank 1, the etching tank 1 is connected with the liquid storage tank 2 through the through hole 3, a workbench 4 is slidably installed on the upper surface of the bottom plate of the etching tank 1, a wafer rotating chuck 5 is horizontally rotatably installed on the workbench 4, a cavity 6 is arranged in the workbench 4, the bottom of the wafer rotating chuck 5 extends downward into the cavity 6, a driving mechanism 7 for driving the wafer rotating chuck 5 to rotate back and forth is arranged in the cavity 6, a through discharge port 8 is opened at the position of the workbench 4 corresponding to the through hole 3, and the bottom of the liquid storage tank 2 is fixedly installed A heating pipe 9 is installed, and an anti-corrosion pump 10 is arranged on the outside of one side of the liquid storage tank 2. The input end of the anti-corrosion pump 10 is fixedly connected to a liquid inlet pipe 11, and the end of the liquid inlet pipe 11 away from the anti-corrosion pump 10 passes through the side wall of the liquid storage tank 2 and extends to the inside of the liquid storage tank 2. The output end of the anti-corrosion pump 10 is fixedly connected to a discharge pipe 12. Support blocks 13 are arranged around the etching tank 1 near the top, and a spraying tank 14 is fixedly installed on the support block 13. A plurality of nozzles 15 are arranged on the lower surface of the spraying tank 14, and the nozzles 15 are distributed in a circle. The end of the discharge pipe 12 away from the anti-corrosion pump 10 passes through the side wall of the etching tank 1 and is connected to the spraying tank 14.

[0021] A sealing portion 16 is provided at one end of the workbench 4 away from the drain port 8, and a downwardly inclined inclined portion 17 is provided on the side of the sealing portion 16 facing the drain port 8. The lower end of the inclined portion 17 extends between the wafer rotating chuck 5 and the drain port 8, and the wafer rotating chuck 5 and the inclined portion 17 are sealed and rotatably connected.

[0022] The sealing portion 16 passes through the side wall of the corresponding etching groove 1 and extends to the outside of the etching groove 1 , and the sealing portion 16 and the side wall of the etching groove 1 are slidably connected.

[0023] The driving mechanism 7 includes an electric telescopic rod 18, a rack 19 and a gear 20 matching the rack 19. The gear 20 is fixedly mounted on the bottom of the wafer rotating chuck 5. The bottom of the gear 20 is rotatably connected to the workbench 4. The electric telescopic rod 18 is fixedly mounted on a side of the cavity 6 away from the gear 20. One end of the rack 19 is fixedly connected to the output end of the electric telescopic rod 18, and the other end is meshed with the gear 20.

[0024] One end of the liquid inlet pipe 11 located in the liquid storage bin 2 is fixedly connected to a filter 21 .

[0025] The nozzles 15 are provided with multiple layers from the outside to the inside and are coaxial with the wafer rotating chuck 5 . The nozzles 15 on the outermost layer face the edge of the wafer rotating chuck 5 .

[0026] Working principle or structural principle: First, start the heating tube 9 to heat the solution, and pull the workbench 4 out of the etching tank 1, install the wafer to be etched on the wafer rotating chuck 5, then push the workbench 4 into the etching tank 1, start the anti-corrosion pump 10 and the electric telescopic rod 18, the anti-corrosion pump 10 pumps the solution in the liquid storage tank 2, the solution is filtered through the filter 21 and then transported to the spraying tank 14 through the liquid inlet pipe 11 and the liquid discharge pipe 12, and then sprayed through the nozzle 15, the electric telescopic rod 18 drives the rack 19 to move back and forth, thereby driving the gear 20 to rotate back and forth, and the gear 20 drives the wafer rotating chuck 5 Rotating synchronously with the wafer, the solution sprayed from the nozzle 15 is distributed to the surface of the wafer to etch the wafer, and then the centrifugal force of the rotation of the wafer rotating chuck 5 causes the etched solution to flow to the inclined portion 17 of the workbench 4, so that the solution flows from the inclined portion 17 to the drain port 8, and finally flows from the drain port 8 through the through hole 3 and returns to the liquid storage tank 2. Since the nozzles 15 are distributed in multiple layers in a circle and are concentric with the wafer rotating chuck 5, the solution can be evenly sprayed on the surface of the wafer, avoiding the problem that the etching rate in the center of the wafer is higher than that at the edge, resulting in poor uniformity of the entire wafer, thereby improving the etching uniformity of the wafer.

[0027] So far, the embodiments of the utility model have been described in detail in conjunction with the accompanying drawings. It should be noted that the implementation methods not shown or described in the drawings or the body of the specification are all forms known to ordinary technicians in the relevant technical field and are not described in detail. In addition, the above definitions of each component are not limited to the various specific structures, shapes or methods mentioned in the embodiments, and ordinary technicians in the field can simply change or replace them.

[0028] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways, even if such combinations and / or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All of these combinations and / or combinations fall within the scope of the present invention.

[0029] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wafer wet etching device, comprising an etching tank (1), characterized in that: A liquid storage tank (2) is fixedly installed at the bottom of the etching tank (1), a through hole (3) is provided on one side of the bottom plate of the etching tank (1), and the etching tank (1) is connected to the liquid storage tank (2) through the through hole (3). A workbench (4) is slidably installed on the upper surface of the bottom plate of the etching tank (1), and a wafer rotating chuck (5) is horizontally rotatably installed on the workbench (4). A cavity (6) is provided in the workbench (4), and the bottom of the wafer rotating chuck (5) extends downward into the cavity (6). A driving mechanism (7) for driving the wafer rotating chuck (5) to rotate back and forth is provided in the cavity (6). A through discharge port (8) is provided on the workbench (4) at a position corresponding to the through hole (3). A heating pipe (9) is fixedly installed at the bottom of the liquid storage tank (2). An anti-corrosion pump (10) is arranged on the outside of one side of the liquid storage bin (2), and the input end of the anti-corrosion pump (10) is fixedly connected to a liquid inlet pipe (11), and the end of the liquid inlet pipe (11) away from the anti-corrosion pump (10) passes through the side wall of the liquid storage bin (2) and extends to the inside of the liquid storage bin (2), and the output end of the anti-corrosion pump (10) is fixedly connected to a liquid discharge pipe (12), and a support block (13) is arranged around the etching tank (1) near the top, and a spray bin (14) is fixedly installed on the support block (13), and a plurality of nozzles (15) are arranged on the lower surface of the spray bin (14), and the nozzles (15) are distributed in a circular shape, and the end of the liquid discharge pipe (12) away from the anti-corrosion pump (10) passes through the side wall of the etching tank (1) and is connected to the spray bin (14).

2. A wafer wet etching device according to claim 1, characterized in that: A sealing portion (16) is provided at one end of the workbench (4) away from the drain port (8), and a downwardly inclined inclined portion (17) is provided on the side of the sealing portion (16) facing the drain port (8), and the lower end of the inclined portion (17) extends between the wafer rotating chuck (5) and the drain port (8), and the wafer rotating chuck (5) and the inclined portion (17) are sealed and rotatably connected.

3. A wafer wet etching device according to claim 2, characterized in that: The sealing portion (16) passes through the side wall of the corresponding etching groove (1) and extends to the outside of the etching groove (1), and the sealing portion (16) and the side wall of the etching groove (1) are slidably connected.

4. A wafer wet etching device according to claim 1, characterized in that: The driving mechanism (7) comprises an electric telescopic rod (18), a rack (19) and a gear (20) matched with the rack (19); the gear (20) is fixedly mounted on the bottom of the wafer rotating chuck (5); the bottom of the gear (20) is rotatably connected to the workbench (4); the electric telescopic rod (18) is fixedly mounted on a side of the cavity (6) away from the gear (20); one end of the rack (19) is fixedly connected to the output end of the electric telescopic rod (18), and the other end is meshed with the gear (20).

5. The wafer wet etching device according to claim 1, characterized in that: One end of the liquid inlet pipe (11) located in the liquid storage bin (2) is fixedly connected to a filter (21).

6. A wafer wet etching device according to claim 1, characterized in that: The nozzles (15) are provided with multiple layers from the outside to the inside and are cocentric with the wafer rotating chuck (5), and the outermost layer of the nozzles (15) is facing the edge of the wafer rotating chuck (5).

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