Regeneration wafer metal film etching equipment

Abstract

The application discloses a kind of regenerative wafer metal film corrosion equipment, including two groups of etching tank, the etching tank includes bent plate and two groups of movable base plate, the outer wall of two groups of movable base plate is provided with the elastic sealing ring of bent structure, two groups of movable base plate are movably arranged in the bent cavity of bent plate and form sealing to the bottom of bent plate, two groups of etching tank are installed above the material receiving groove, also be provided with rotary discharging structure, for driving two groups of bent plate rotation, so that the precipitate on the upper end of bent plate falls into the material receiving groove by its gravity effect.The etching tank is provided with rotary discharging structure, can control two groups of movable base plate to rotate by rotary discharging structure, to remove the sealing to the bottom of bent plate, so that bent plate mixed solution falls into the material receiving groove by its gravity, precipitate falls into the material receiving groove by its gravity and the scouring of water flow flow, avoid manual cleaning, reduce labor intensity.

Description

Technical Field

[0001] This invention relates to the field of regenerated wafer processing technology, and in particular to a metal film etching device for regenerated wafers. Background Technology

[0002] In the semiconductor manufacturing field, as the feature size of integrated circuits continues to shrink, the requirements for wafer surface flatness and the precision of metal film removal are becoming increasingly stringent. In the reclaimed wafer manufacturing process, metal film etching is a critical step, and its process stability directly determines the wafer's reusability and device performance. Currently, the mainstream technology in the industry is to alternately etch the metal film on the surface of the reclaimed wafer using two etchants of different concentrations.

[0003] Specifically, the process typically involves first etching the wafer in a high-concentration mixture of hydrofluoric acid, nitric acid, and acetic acid for a period of time, then switching to a diluted solution of the same type for further etching, followed by another period of etching in the high-concentration mixture. This alternating etching process, using a combination of fast and slow chemical reactions, achieves synergistic optimization across efficiency, quality, cost, and environmental protection. This has propelled semiconductor manufacturing towards higher precision, lower cost, and greater sustainability, providing crucial technological support for the large-scale application of regenerated wafers.

[0004] In actual operation, sediment will be generated at the bottom of the etching tank. After each etching is completed, the sediment at the bottom of the etching tank needs to be cleaned manually, which is quite troublesome. Therefore, this application provides a regenerated wafer metal film etching equipment to meet the needs. Summary of the Invention

[0005] The purpose of this application is to provide a metal film etching device for regenerated wafers, which solves the technical problem of manual cleaning of sediment at the bottom of the etching tank in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solution: a metal film etching device for regenerated wafers, comprising two sets of etching tanks, each etching tank including a U-shaped plate and two sets of movable base plates. The outer walls of the two sets of movable base plates are provided with elastic sealing rings of a U-shaped structure. The two sets of movable base plates are movably disposed within the U-shaped cavity of the U-shaped plate and form a seal on the bottom of the U-shaped plate. The two sets of etching tanks are installed above a receiving tank. A rotating feeding structure is also provided to drive the two sets of movable base plates to rotate, so that the precipitate on the upper part of the movable base plates falls into the receiving tank by its own gravity.

[0007] As a preferred embodiment of this example, the rotary feeding structure includes a drive motor mounted on the outer wall of the corrosion tank, first pulleys mounted on corresponding rotating shafts, and second pulleys mounted on the output shaft of the drive motor.

[0008] Both sets of movable base plates are rotatably connected to the corrosion tank via corresponding rotating shafts, with the drive end of the rotating shaft penetrating the corrosion tank;

[0009] Both sets of the first pulleys and one set of the second pulleys are connected by belt assembly;

[0010] The drive motor is mounted on the outer wall of the corrosion tank.

[0011] As a preferred embodiment of this invention, a pneumatic sealing structure is also provided, which includes a cylinder and a piston cylinder installed on the outer wall of the corrosion tank.

[0012] A sealing piston is installed at the lower end of the cylinder, and the lower end of the sealing piston is slidably disposed in the inner cavity of the piston cylinder. Air pipes communicating with the inner cavity of the piston cylinder are provided on both outer walls of the piston cylinder, and the air inlet ends of the two sets of air pipes are sealed and rotatably connected to the ends of the corresponding rotating shafts.

[0013] The rotating shaft is provided with an air inlet, and the air inlet is connected to the inflation chamber of the inner cavity of the elastic sealing ring through a connecting hose. The inner cavity of the rotating shaft is provided with a gas flow channel that communicates with the air inlet and the inner cavity of the air pipe.

[0014] As a preferred embodiment of this invention, an auxiliary feeding structure is also provided to assist in the feeding of sediments onto the movable base plate.

[0015] As a preferred embodiment of this example, the auxiliary feeding structure includes a magnetic shielding ring coaxially arranged with the rotating shaft. The magnetic shielding ring has multiple grooves arranged circumferentially on the end face facing the corrosion tank, and a first permanent magnet and a second permanent magnet are respectively arranged in adjacent grooves at intervals.

[0016] The movable base plate has a groove at the end near the magnetic shielding ring, and a third permanent magnet is provided in the groove. A through hole is provided on the elastic sealing ring corresponding to the third permanent magnet.

[0017] The third permanent magnet has opposite magnetic poles at its opposite ends to the first permanent magnet, and the third permanent magnet has the same magnetic poles at its opposite ends as the second permanent magnet;

[0018] The upper end of the rotating shaft is fixed with a limiting strip, which is movably disposed in the inner cavity corresponding to the movable base plate. The movable base plate is movably connected to the rotating shaft and is provided with a movable cavity adapted to the rotating shaft and the limiting strip.

[0019] In a preferred embodiment of this invention, the magnetic shielding ring does not have a first permanent magnet and a second permanent magnet disposed along the X-axis.

[0020] In a preferred embodiment of this invention, the two sets of corrosion tanks are arranged at different heights. The outer wall of the corrosion tank at the higher height is provided with a drain pipe that can drain liquid into the corrosion tank at the lower height, and a valve is installed on the drain pipe.

[0021] In a preferred embodiment of this invention, both sets of the spiral plates are provided with ultrasonic generators and electric heating tubes on their inner walls.

[0022] In summary, the technical effects and advantages of this invention are as follows:

[0023] 1. The present invention has a reasonable structure. The corrosion tank is equipped with a rotating feeding structure. The two sets of movable bottom plates can be rotated by the rotating feeding structure, thereby releasing the seal on the bottom of the U-shaped plate. The mixture of the U-shaped plate falls into the receiving tank by its own gravity, and the sediment falls into the receiving tank by its own gravity and the flushing of the water flow, avoiding manual cleaning and reducing labor intensity.

[0024] 2. In this invention, a pneumatic sealing structure and an auxiliary feeding structure are provided. The two work together to avoid frictional loss of the elastic sealing ring and improve the sealing effect. At the same time, the movable base plate can move back and forth on the rotating shaft and collide with the inner wall of the corrosion tank, promoting the falling of the sediment on the movable base plate. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 for Figure 1 Schematic diagram of the rotating feeding structure;

[0028] Figure 3 for Figure 2 Schematic diagram of the movable base plate structure;

[0029] Figure 4 for Figure 3 Schematic diagram of the partial split structure in the middle;

[0030] Figure 5 for Figure 4 Schematic diagram of the transfer shaft structure;

[0031] Figure 6 for Figure 4 Schematic diagram of the central magnetic ring structure;

[0032] Figure 7 for Figure 4 Schematic diagram of the cross-sectional structure of the movable base plate.

[0033] In the diagram: 1. Receiving trough; 2. Etching tank; 3. Rotary feeding structure; 4. Pneumatic sealing structure; 5. Magnetic shielding ring; 6. First permanent magnet; 7. Third permanent magnet; 8. Air inlet; 9. Drain pipe; 10. Second permanent magnet; 11. Inflation chamber; 12. Limiting strip;

[0034] 21. Herringbone plate; 22. Movable base plate;

[0035] 31. Drive motor; 32. First pulley; 33. Second pulley; 34. Belt; 35. Elastic sealing ring; 36. Shaft;

[0036] 41. Cylinder; 42. Piston cylinder; 43. Air pipe. Detailed Implementation

[0037] 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.

[0038] Example: Reference Figure 1-3 The regenerated wafer metal film etching equipment shown includes two sets of etching tanks 2. Each etching tank 2 includes a U-shaped plate 21 and two sets of movable base plates 22. The outer walls of the two sets of movable base plates 22 are provided with U-shaped elastic sealing rings 35. The two sets of movable base plates 22 are movably disposed in the U-shaped cavity of the U-shaped plate 21 and form a seal on the bottom of the U-shaped plate 21. The two sets of etching tanks 2 are installed above the receiving tank 1. A rotating feeding structure 3 is also provided to drive the two sets of movable base plates 22 to rotate, so that the deposits on the upper end of the movable base plates 22 fall into the receiving tank 1 by their own gravity.

[0039] In use, the rotating feeding structure 3 is controlled by the PLC controller. The rotating feeding structure 3 can control the two sets of movable base plates 22 to rotate, thereby releasing the seal on the bottom of the spiral plate 21. This allows the mixture in the spiral plate 21 to fall into the receiving tank 1 by its own gravity, and the sediment falls into the receiving tank by its own gravity and the flushing of the water flow, avoiding manual cleaning and reducing labor intensity.

[0040] It should be noted that: First, the movable base plate 22 is rotated 180° and finally the lower end face of the movable base plate 22 faces upward to form a seal on the bottom of the corrosion tank 2; Second, two sets of movable base plates 22 are set up. The two sets of movable base plates 22 rotate at the same time, which can open multiple water leakage points at the same time. This is conducive to the rapid discharge of the corrosion liquid in the corrosion tank 2 while also preserving enough water flow to flush the movable base plate 22.

[0041] As a preferred embodiment of this example, Figure 1-3 As shown, the rotary feeding structure 3 includes a drive motor 31 mounted on the outer wall of the corrosion tank 2, a first pulley 32 mounted on a corresponding rotating shaft 36, and a second pulley 33 mounted on the output shaft of the drive motor 31.

[0042] Both sets of movable base plates 22 are rotatably connected to the corrosion tank 2 via corresponding rotating shafts 36, with the drive end of the rotating shaft 36 penetrating through the corrosion tank 2;

[0043] The two sets of first pulleys 32 and the set of second pulleys 33 are all connected by belts 34;

[0044] The drive motor 31 is mounted on the outer wall of the corrosion tank 2.

[0045] During operation, the second pulley 38 can be driven to rotate by the drive motor 31. The two sets of rotating shafts 36 are rotated by the belt 34 and the two sets of first pulleys 32, which in turn drive the two sets of movable base plates 22 to rotate. After rotating 180°, they return to their original positions. During this process, the mixture of the shaped plate 21 falls into the receiving tank 1 by its own gravity, and the sediment falls into the receiving tank by its own gravity and the flushing of the water flow, avoiding manual cleaning and reducing labor intensity. In particular, when the movable base plate 22 tilts during rotation, it is more conducive to the discharge of sediment on the movable base plate 22.

[0046] It should be noted that initially, the outer walls of both sets of elastic sealing rings 35 (except for the opposite ends, the opposite ends of the two sets of elastic sealing rings 35 abut against each other) abut against the inner wall of the corrosion tank 2, forming a seal.

[0047] As a preferred embodiment of this example, Figure 1-5As shown, a pneumatic sealing structure 4 is also provided, which includes a cylinder 41 and a piston cylinder 42 installed on the outer wall of the corrosion tank 2.

[0048] A sealing piston is installed at the lower end of the cylinder 41, and the lower end of the sealing piston is slidably disposed in the inner cavity of the piston cylinder 42. Air pipes 43 communicating with the inner cavity of the piston cylinder 42 are provided on both outer walls of the piston cylinder 42, and the air inlet ends of the two sets of air pipes 43 are sealed and rotatably connected to the ends of the corresponding rotating shafts 36.

[0049] The rotating shaft 36 is provided with an air inlet 8, and the air inlet 8 is connected to the inflation chamber 11 of the inner cavity of the elastic sealing ring 35 through a connecting hose. The inner cavity of the rotating shaft 36 is provided with a gas flow channel that communicates with the air inlet 8 and the inner cavity of the air pipe 43.

[0050] Before controlling the drive motor 31 to work, first control the cylinder 41 to drive the piston to move upward, so that the air pressure inside the inflation chamber 11 decreases, the elastic sealing ring 35 contracts and separates from the inner wall of the corrosion groove 2, and also separates from the opposite end of the corresponding movable base plate 22. At this time, the drive motor 31 can be controlled to work to drive the movable base plate 22 to rotate. After the movable base plate 22 rotates 180°, control the cylinder 41 to move downward and return to its original position. At this time, the gas in the piston cylinder 42 is compressed into the inflation chamber 11 through the action of the piston. The inflation chamber 11 expands, so that the outer wall of the elastic sealing ring 35 seals against the outer wall of the corrosion groove 2 and the opposite end of the corresponding elastic sealing ring 35. This can prevent the elastic sealing ring 35 from rubbing against the corrosion groove 2 during the rotation of the movable base plate 22, which would cause wear. The sealing effect of the elastic sealing ring 35 that is worn will be greatly reduced.

[0051] As a preferred embodiment of this invention, an auxiliary feeding structure is also provided to assist in the feeding of sediment on the movable base plate 22.

[0052] The auxiliary feeding structure makes it easier to completely remove the sediment on the upper part of the movable base plate 22.

[0053] As a preferred embodiment of this example, Figure 4-7 As shown, the auxiliary feeding structure includes a magnetic shielding ring 5 coaxially arranged with the rotating shaft 36. The magnetic shielding ring 5 has multiple grooves arranged in a circle on the end face facing the corrosion tank 2, and a first permanent magnet 6 and a second permanent magnet 10 are respectively arranged in adjacent grooves at intervals.

[0054] The movable base plate 22 has a groove at the end near the magnetic shielding ring 5, and a third permanent magnet 7 is provided in the groove. A through hole is provided on the elastic sealing ring 35 corresponding to the third permanent magnet 7.

[0055] The third permanent magnet 7 has opposite magnetic poles to the first permanent magnet 6 at its opposite ends, and the third permanent magnet 7 has the same magnetic poles to the second permanent magnet 10 at its opposite ends.

[0056] The upper end of the rotating shaft 36 is fixed with a limiting strip 12, which is movably disposed in the inner cavity of the corresponding movable base plate 22. The movable base plate 22 is movably connected to the rotating shaft 36 and is provided with a movable cavity adapted to the rotating shaft 36 and the limiting strip 12.

[0057] As the drive motor 31 drives the two movable base plates 22 to rotate (at this time, the outer wall of the elastic sealing ring 35 does not contact the corrosion tank 2 and the outer wall of the opposite elastic sealing ring 35, and a gap is generated between the outer wall of the elastic sealing ring 35 and the inner wall of the corrosion tank 2), during this process, the third permanent magnet 7 on the movable base plate 22 will move to a position opposite to the first permanent magnet 6 (at this time, the corrosion liquid in the corrosion tank 2 has been discharged, and there are a few difficult-to-remove sediments remaining on the upper end of the movable base plate 22). At this time, the opposite magnetic poles generate attraction, causing the movable base plate 22 to rotate on the shaft. The movable base plate 22 slides on the shaft 36 and impacts the interior of the corrosion tank 2, shaking off the sediment on the movable base plate 22. When the third permanent magnet 7 moves to the relative position of the adjacent second permanent magnet 10, the repulsive force is generated by the same magnetic poles, causing the movable base plate 22 to move away from the second permanent magnet 10 on the shaft 36 and eventually impact the interior of the corrosion tank 2, promoting the falling of the sediment on it. This process is repeated, and the movable base plate 22 moves back and forth on the shaft 36 to form collisions, which can completely remove the sediment on the movable base plate 22 without the need for rinsing with water, thus saving water resources.

[0058] It should be noted that the corrosion tank 2 is made of a non-magnetic material.

[0059] As a preferred embodiment of this example, Figure 6 As shown, the first permanent magnet 6 and the second permanent magnet 10 are not provided on the axis of the magnetic shielding ring 5 along the X-axis.

[0060] The purpose is to ensure that when the two sets of movable base plates 22 are horizontally positioned inside the cavity of the U-shaped plate 21 and form a seal on the U-shaped plate 21, the third permanent magnet 7 is not positioned opposite to the first permanent magnet 6 and the second permanent magnet 10, thus preventing the generation of attraction or repulsion. This avoids the elastic sealing ring 35 from being excessively compressed due to magnetic action, which would reduce the compressive strength between the corresponding side and the inside of the corrosion tank 2, thus hindering a good seal between the elastic sealing ring 35 and the corrosion tank 2.

[0061] As a preferred embodiment of this example, Figure 1As shown, the two sets of corrosion tanks 2 are arranged at different heights. The outer wall of the corrosion tank 2 at the higher height is provided with a drain pipe 9 that can drain liquid into the corrosion tank 2 at the lower height, and a valve is installed on the drain pipe 9.

[0062] In practical use, after the high-concentration etchant has finished etching, the concentration of the etchant inside is sufficient to meet the demand for the low-concentration etchant. To avoid wasting resources, the high-concentration etchant is placed in the high-concentration etchant tank 2, and the low-concentration etchant is placed in the low-concentration etchant tank 2. After the wafer is etched, the etchant in the low-concentration etchant tank 2 is directly discharged into the receiving tank 1, and the etchant in the high-concentration etchant tank 2 is discharged into the low-concentration etchant tank 2 for reuse.

[0063] It should be noted that the drain pipe 9 is located above the sediment.

[0064] As a preferred embodiment of this invention, not shown in the figure, both sets of U-shaped plates 21 are provided with ultrasonic generators and electric heating tubes on their inner walls.

[0065] When using the etching solution in etching tank 2 to etch the wafer, the assistance of an ultrasonic generator and an electric heating tube (temperature control) makes it easier to achieve rapid and comprehensive etching of the wafer.

[0066] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A metal film etching device for regenerated wafers, comprising two sets of etching tanks (2), characterized in that: The corrosion tank (2) includes a U-shaped plate (21) and two sets of movable base plates (22). The outer walls of the two sets of movable base plates (22) are provided with elastic sealing rings (35) of U-shaped structure. The two sets of movable base plates (22) are movably arranged in the U-shaped cavity of the U-shaped plate (21) and form a seal on the bottom of the U-shaped plate (21). The two sets of corrosion tanks (2) are installed above the receiving tank (1) and are also provided with a rotating feeding structure (3) for driving the two sets of movable base plates (22) to rotate, so that the sediment at the upper end of the movable base plate (22) falls into the receiving tank (1) by its own gravity. The rotary feeding structure (3) includes a drive motor (31) mounted on the outer wall of the corrosion tank (2), a first pulley (32) mounted on the corresponding rotating shaft (36), and a second pulley (33) mounted on the output shaft of the drive motor (31). Both sets of movable base plates (22) are rotatably connected to the corrosion tank (2) through corresponding rotating shafts (36), and the driving end of the rotating shaft (36) passes through the corrosion tank (2). Both sets of the first pulleys (32) and one set of the second pulleys (33) are connected by belts (34); The drive motor (31) is mounted on the outer wall of the corrosion tank (2); A pneumatic sealing structure (4) is also provided, which includes a cylinder (41) and a piston cylinder (42) installed on the outer wall of the corrosion tank (2). A sealing piston is installed at the lower end of the cylinder (41), and the lower end of the sealing piston is slidably disposed in the inner cavity of the piston cylinder (42). Air pipes (43) communicating with the inner cavity of the piston cylinder (42) are provided on both outer walls of the piston cylinder (42), and the air inlet ends of the two sets of air pipes (43) are sealed and rotatably connected to the end of the corresponding rotating shaft (36). The rotating shaft (36) is provided with an air inlet (8), and the air inlet (8) is connected to the inflation chamber (11) of the inner cavity of the elastic sealing ring (35) through a connecting hose. The inner cavity of the rotating shaft (36) is provided with a gas flow channel that is connected to the air inlet (8) and the inner cavity of the air pipe (43).

2. The metal film etching equipment for regenerated wafers according to claim 1, characterized in that: An auxiliary feeding structure is also provided to assist in the feeding of sediment on the movable base plate (22).

3. The metal film etching equipment for regenerated wafers according to claim 2, characterized in that: The auxiliary feeding structure includes a magnetic shielding ring (5) coaxially arranged with the rotating shaft (36). The magnetic shielding ring (5) has multiple grooves arranged in a circle on the end face facing the corrosion tank (2), and a first permanent magnet (6) and a second permanent magnet (10) are respectively arranged in adjacent grooves. The movable base plate (22) has a groove at the end near the magnetic shielding ring (5), and a third permanent magnet (7) is provided in the groove. A through hole is provided on the part of the elastic sealing ring (35) corresponding to the third permanent magnet (7). The third permanent magnet (7) has opposite magnetic poles to the first permanent magnet (6), and the third permanent magnet (7) has the same magnetic poles to the second permanent magnet (10). The upper end of the rotating shaft (36) is fixed with a limiting strip (12), which is movably disposed in the inner cavity of the corresponding movable base plate (22). The movable base plate (22) is movably connected to the rotating shaft (36) and is provided with a movable cavity that is adapted to the rotating shaft (36) and the limiting strip (12).

4. The metal film etching equipment for regenerated wafers according to claim 3, characterized in that: The magnetic shielding ring (5) does not have a first permanent magnet (6) and a second permanent magnet (10) along the X-axis.

5. The metal film etching equipment for regenerated wafers according to claim 1, characterized in that: The two sets of corrosion tanks (2) are arranged at different heights. The outer wall of the corrosion tank (2) at the higher height is provided with a drain pipe (9) that can drain liquid to the corrosion tank (2) at the lower height, and a valve is installed on the drain pipe (9).

6. The metal film etching equipment for regenerated wafers according to claim 1, characterized in that: Both sets of the spiral plates (21) are equipped with ultrasonic generators and electric heating tubes on their inner walls.

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