Wafer edge chamfer cutting and cleaning method and cutting and cleaning device

Abstract

A wafer cutting and cleaning device comprises a machine body (10), a cutting station table (20), a rotating mechanism (30), a moving frame (40), an etching system (50), a water jet cutter system (60) and an air knife system (70). The wafer edge chamfer manufacturing method comprises the steps that a wafer is fixed to a machining station, and a machining station rotating mechanism is started to rotate the wafer; an etching liquid nozzle is moved to the position close to the edge of the wafer, and etching liquid is sprayed to the edge of the wafer; the high-pressure water nozzle is moved to the position near the edge of the wafer sprayed with the etching liquid previously, the high-pressure water jet cutter is started, and jet cutting is conducted on the etched position of the wafer according to a preset angle; then a high-pressure air knife installed together with the high-pressure water nozzle is started, and the surface cut by the water knife is further subjected to jet cutting and trimming according to the preset angle; and feeding the wafer into a cleaning station for later cleaning. According to the invention, the accuracy of the cutting angle in the chamfering process can be ensured, and the completeness of the wafer and the intact internal structure can be effectively protected.

Description

Technical Field

[0002] The present invention relates to the technical field of wafer processing, and in particular to a wafer edge chamfering, cutting and cleaning method and equipment. Background Art

[0003] Wafer chamfering is a commonly used technology at present. Its main purpose is to prevent the wafer edge from breaking. During the manufacturing and use of wafers, they are often hit by robots, etc., which causes the wafer edge to break and form stress concentration areas. These stress concentration areas will cause the wafer to continuously release contaminants during use, thereby affecting the product yield. Second, prevent the concentration of thermal stress. When the wafer is in use, it will undergo countless high-temperature processes, such as oxidation and diffusion. When the thermal stress generated in these processes exceeds the strength of the silicon lattice, dislocation and stacking fault defects will occur. Rounding the edge of the wafer can prevent such defects from occurring at the edge of the wafer. Third, increase the flatness of the epitaxial layer and the photoresist layer at the edge of the wafer. In the epitaxial process, the growth rate of the sharp angle area will be higher than that of the flat surface. Therefore, it is easy to produce protrusions on the edge of the wafer without rounding. Similarly, when applying photoresist using a spin coater, the photoresist solution will also accumulate at the edge of the wafer. These uneven edges will affect the focus accuracy of the mask.

[0004] The existing methods for making chamfers or inclined planes on wafer edges include mechanical grinding, laser cutting, and etching. Although mechanical grinding and laser cutting are more convenient and economical, they also have the following problems, such as easy generation of broken pieces, poor uniformity, and foreign matter contamination. The simple etching method has poor control accuracy and is prone to erosion of the surrounding wafers. Summary of the invention

[0005] The present invention adopts a method combining etching and cutting, and particularly adopts a water and wind cutting method which is less harmful to the wafer, thereby avoiding the technical problem of easily damaging the wafer in the prior art.

[0006] The cutting and cleaning equipment designed by the present invention to solve the above-mentioned technical problems includes a machine body, a cutting station arranged in the machine body, a rotating mechanism for driving the cutting station, and a movable frame arranged above the cutting station. The machine body is also provided with an etching system, a water knife system and an air knife system. The etching liquid nozzle in the etching system, the high-pressure water knife nozzle in the water knife system and the high-pressure air knife nozzle in the air knife system are installed on the movable frame. The cutting and cleaning device also includes a control system for controlling the above-mentioned systems and the rotating mechanism.

[0007] The further improvement of the present invention is that: the etching system also includes an etching liquid tank, an etching liquid pipeline for conveying the etching liquid to the etching liquid nozzle, and an etching liquid amount adjustment mechanism for controlling the opening size of the etching liquid nozzle. The water knife system also includes a water tank, a booster water pump, a high-pressure water pipeline for conveying high-pressure water to the high-pressure water knife nozzle, and a first angle adjuster arranged on the high-pressure water knife nozzle. The air knife system also includes a booster air pump connected to an air source, a high-pressure air pipeline for conveying high-pressure air to the high-pressure air knife nozzle, and a second angle adjuster arranged on the high-pressure air knife nozzle.

[0008] In order to ensure the accuracy of the cutting angle, the first angle adjuster and the second angle adjuster of the present invention are both servo motors, and the rotation angles of the high-pressure water knife nozzle and the high-pressure air knife nozzle are controlled by the deceleration system, and the servo motors are controlled by the control system. Or the first angle adjuster is a contour adjuster, including a contour plate, a first mold roller fixed on the high-pressure water knife nozzle abuts against the contour edge of the contour plate, and also includes a first elastic member for abutting the high-pressure water knife nozzle. The second angle adjuster is a contour adjuster, including a contour plate, a second mold roller fixed on the high-pressure air knife nozzle abuts against the contour edge of the contour plate, and also includes a second elastic member for abutting the high-pressure air knife nozzle, and the first elastic member and the second elastic member are both rubber piles.

[0009] The method for performing wafer chamfering processing using the cutting and cleaning equipment is as follows: the method comprises the following steps: a. First, fix the wafer on the processing position, start the processing position rotating mechanism to rotate the wafer, and the rotating mechanism gradually decreases as the etching liquid nozzle gradually moves toward the edge; b. Move the etching liquid nozzle to the edge of the wafer and spray the etching liquid to the edge of the wafer. The amount of etching liquid sprayed increases as the nozzle moves toward the edge. c. After the etching liquid stays on the wafer surface for a period of time, the high-pressure water nozzle is moved to the edge of the wafer previously sprayed with the etching liquid, and the high-pressure water jet is turned on to spray and cut the etched position of the wafer at a predetermined angle. The high-pressure water jet gradually increases as it moves toward the edge; d. After step C is completed, the high-pressure air knife installed together with the high-pressure water nozzle is started, and the surface cut by the water jet is further jetted and cut and trimmed at a predetermined angle. The high-pressure air knife gradually increases in size as it moves toward the edge; e. Send the wafer to the cleaning station for post-cleaning.

[0010] The present invention adopts the above technical solution, which can ensure the accuracy of the cutting angle during the chamfering process and effectively protect the integrity of the chip and the integrity of the internal structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic diagram of a wafer chamfering cutting process according to the present invention; Figure 2 is a schematic diagram of a mobile frame of a cutting and cleaning device of the present invention; Figure 3 is a cross-sectional schematic diagram of an etching liquid nozzle of the present invention; Figure 4 It is a working schematic diagram of the first and second angle adjusters of the present invention. DETAILED DESCRIPTION

[0012] The specific embodiments of the present invention are described in conjunction with the above drawings.

[0013] Depend on Figure 1 It can be seen that the cutting and cleaning device in the present invention includes a body 10, a cutting station 20 arranged in the body, a rotating mechanism 30 for driving the cutting station 20, and also includes a movable frame 40 arranged above the cutting station. The body is also provided with an etching system 50, a water knife system 60 and an air knife system 70. The etching liquid nozzle 51 in the etching system 50, the high-pressure water knife nozzle 61 in the water knife system 60 and the high-pressure air knife nozzle 71 in the air knife system 70 are installed on the movable frame 40. The cutting and cleaning device also includes a control system 80 for controlling the above-mentioned systems and the rotating mechanism. The method for using the device to perform chamfer cutting and cleaning of wafers includes the following steps: a. first, fix wafer A on the processing position, and start the processing position rotating mechanism to rotate the wafer; b. move the etching liquid nozzle to the vicinity of the wafer edge, and spray the etching liquid to the wafer edge; c. after the etching liquid stays on the wafer surface for a period of time, move the high-pressure water nozzle to the vicinity of the wafer edge previously sprayed with the etching liquid, start the high-pressure water jet, and spray and cut the etched position of the wafer at a predetermined angle; d. after step C is completed, start the high-pressure air knife installed together with the high-pressure water nozzle, and further spray and cut the surface cut by the water jet at a predetermined angle; e. send the wafer to the cleaning station for post-cleaning. This combination of processing mainly involves softening the wafer when the etching liquid is sprayed and etched on the designated area of ​​the wafer. In this way, the water knife and air knife are used to cut the wafer in the softened state. This can avoid the problem that long-term wafer etching may damage the surrounding tissue. The softened tissue can be completely borne by the wafer itself, and the wafer itself will not cause physical damage to it, thereby ensuring the safety of the wafer itself. Since the angle adjustment method is used for cutting, the precise cutting of the chamfer is also guaranteed.

[0014] Depend on Figures 1 to 3It can be seen that the etching system 50 in the present invention also includes an etching liquid tank 52, an etching liquid pipeline 53 for conveying etching liquid to the etching liquid nozzle 51, and an etching liquid amount adjustment mechanism 54 for controlling the opening size of the etching liquid nozzle 51. The water knife system 60 also includes a water tank 62, a booster pump 63, a high-pressure water pipeline 64 for conveying high-pressure water to the high-pressure water knife nozzle 61, and a first angle adjuster 65 arranged on the high-pressure water knife nozzle 61, and the air knife system 70 also includes a booster pump 62 connected to the wind source, a high-pressure air pipeline 73 for conveying high-pressure air to the high-pressure air knife nozzle 71, and a second angle adjuster 74 arranged on the high-pressure air knife nozzle 71. In the present invention, the movable frame is a fan-shaped structure, wherein the etching liquid nozzle 51, the high-pressure water knife nozzle 61 and the high-pressure air knife nozzle 71 are all installed in the same circular position of the movable frame, and the direction is opposite to the rotation direction of the wafer. When the etching liquid is sprayed to the edge of the wafer, etching is carried out. Since the water knife and the air knife are separated from the etching liquid nozzle by a distance, a certain amount of time is given to the etching to ensure that the etched area of ​​the wafer is softened. This distance is set by the corrosion rate of the etching liquid, which can ensure softening without excessive corrosion. The angles of the air knife and the water knife are controlled by the adjustment device to achieve the required angle and shape. By cutting the wafer with the air and water knives, the cooling and preliminary cleaning effects can be further achieved.

[0015] In the present invention, the first angle adjuster 65 and the second angle adjuster 74 are both servo motors, which control the rotation angles of the high-pressure water jet nozzle 61 and the high-pressure air jet nozzle 71 through a reduction system. The servo motors are controlled by the control system 80 (not shown in the figure).

[0016] Depend on Figure 4It can be seen that the first angle adjuster 65 in the present invention is a profiling adjuster, including a profiling plate 651, a first mold roller 652 fixed on the high-pressure water jet nozzle 61 abuts against the profiling edge of the profiling plate 651, and also includes a first elastic member 653 for abutting against the high-pressure water jet nozzle 61. The second angle adjuster 74 is a profiling adjuster, including a profiling plate 741, a second mold roller 742 fixed on the high-pressure air knife nozzle 71 abuts against the profiling edge of the profiling plate 741, and also includes a second elastic member 743 for abutting against the high-pressure air knife nozzle 71, and the first elastic member 653 and the second elastic member 743 are both rubber piles. The contour adjustment structure in this scheme is relatively simple. As the nozzle moves toward the edge of the wafer, the trajectory of the mold roller changes under the control of the contour plate, thereby changing the angle of the controlled nozzle. If the shape of the wafer chamfer is different, the contour plate can be directly replaced. The reliability is relatively high and the precision is relatively accurate. The elastic component 743 in the present invention can ensure the accuracy of the angle adjustment and prevent jumping during the contouring action, and the rubber pile is used as the elastic recovery element, mainly to avoid the possibility of up and down jumping caused by ordinary spring elements, which affects the error of the cutting angle. The rubber pile is not very sensitive to rebound during the compression process, and can absorb a certain compression force to a certain extent, thereby preventing up and down jumping.

[0017] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A wafer edge chamfering cutting and cleaning method, characterized in that: The method comprises the following steps: a. First, fix the wafer on the processing position and start the processing position rotation mechanism to rotate the wafer; b. Move the etching liquid nozzle to the edge of the wafer and spray the etching liquid toward the edge of the wafer; c. After the etching liquid stays on the wafer surface for a period of time, the high-pressure water nozzle is moved to the edge of the wafer previously sprayed with the etching liquid, and the high-pressure water jet is turned on to spray and cut at the etched position of the wafer at a predetermined angle; d. After step C is completed, the high-pressure air knife installed together with the high-pressure water nozzle is started, and the surface cut by the water jet is further jet-cut and trimmed at a predetermined angle; e. Send the wafer to the cleaning station for post-cleaning.

2. The wafer edge chamfering cutting and cleaning method according to claim 1, characterized in that: The rotation speed of the rotating mechanism in step a decreases as the etching liquid nozzle gradually moves toward the edge, and the amount of etching liquid sprayed in step b also increases as the nozzle moves toward the edge.

3. The wafer edge chamfering cutting and cleaning method according to claim 1, characterized in that: The high-pressure water knife and high-pressure air knife in steps c and d gradually increase in size as they move toward the edge.

4. A cutting and cleaning device for implementing the manufacturing method according to any one of claims 1 to 3, characterized in that: The cutting and cleaning device comprises a machine body (10), a cutting station (20) arranged in the machine body, a rotating mechanism (30) for driving the cutting station (20), and a moving frame (40) arranged above the cutting station. The machine body is also provided with an etching system (50), a water knife system (60) and an air knife system (70). The etching liquid nozzle (51) in the etching system (50), the high-pressure water knife nozzle (61) in the water knife system (60) and the high-pressure air knife nozzle (71) in the air knife system (70) are installed on the moving frame (40). The cutting and cleaning device also comprises a control system (80) for controlling the above-mentioned systems and the rotating mechanism.

5. The cutting and cleaning device according to claim 4, characterized in that: The etching system (50) further comprises an etching liquid tank (52), an etching liquid pipeline (53) for conveying the etching liquid to the etching liquid nozzle (51), and an etching liquid amount adjustment mechanism (54) for controlling the opening size of the etching liquid nozzle (51).

6. The cutting and cleaning device according to claim 4, characterized in that: The water knife system (60) further comprises a water tank (62), a booster water pump (63), a high-pressure water pipeline (64) for conveying high-pressure water to the high-pressure water knife nozzle (61), and a first angle adjuster (65) arranged on the high-pressure water knife nozzle (61); the air knife system (70) further comprises a booster air pump (62) connected to an air source, a high-pressure air pipeline (73) for conveying high-pressure air to the high-pressure air knife nozzle (71), and a second angle adjuster (74) arranged on the high-pressure air knife nozzle (71).

7. The cutting and cleaning device according to claim 6, characterized in that: The first angle adjuster (65) and the second angle adjuster (74) are both servo motors, which control the rotation angles of the high-pressure water knife nozzle (61) and the high-pressure air knife nozzle (71) through a speed reduction system, and the servo motors are controlled by the control system (80).

8. The cutting and cleaning device according to claim 6, characterized in that: The first angle adjuster (65) is a contour adjuster, comprising a contour plate (651), a first mold roller (652) fixed on the high-pressure water jet nozzle (61) abutting against a contour edge of the contour plate (651), and a first elastic member (653) for abutting against the high-pressure water jet nozzle (61).

9. The cutting and cleaning device according to claim 6, characterized in that: The second angle adjuster (74) is a contour adjuster, comprising a contour plate (741), a second mold roller (742) fixed on the high-pressure air knife nozzle (71) abutting against the contour edge of the contour plate (741), and also comprising a second elastic member (743) for abutting against the high-pressure air knife nozzle (71).

10. The cutting and cleaning device according to claim 8 or 9, characterized in that: The first elastic component (653) and the second elastic component (743) are both rubber piles.

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