Method for removing movable redundant materials on surface of chip

Abstract

The invention discloses a method for removing movable redundant substances on the surface of a chip. The method comprises the following steps: preparing a soaking solution; determining the position of a redundant object on the surface of the chip by adopting a detection tool; the chip is soaked in the soaking solution, a soft-head brush is used for sweeping the redundant material distribution area on the surface of the chip back and forth for multiple times, and then the chip is shaken in the solution for multiple times and then fished out; drying the surface of the chip by using a high-pressure air gun before the residual soaking solution on the surface of the chip volatilizes; and a detection tool is adopted to detect the redundant material residue condition on the surface of the chip, and whether the preset quality grade requirement is met or not is judged. According to the method, the area of the movable redundant substances is accurately determined, and the movable redundant substances on the surface of the chip can be quickly and effectively removed by combining two treatment modes of the soft-head brush and the high-pressure air gun after the chip is soaked in the soaking solution, so that the surface quality of the chip is improved; the method is simple and efficient to operate, and the cleaning efficiency of the surface of the chip can be improved to a certain extent.

Description

Technical Field

[0001] The invention belongs to the field of chip surface cleaning, and in particular relates to a method for removing movable excess matter on the chip surface. Background Art

[0002] During the packaging process of bare chips such as SMT, welding, and bonding, it is inevitable that metal particles, organic residues and other waste materials will be generated. Large-sized waste materials are easily adsorbed on the chip surface, while smaller-sized waste materials are easily embedded in the gaps of fine lines on the chip surface. The presence of these movable waste materials seriously affects the appearance quality and electrical connection reliability of the chip. At present, the conventional method of processing movable waste materials on the chip surface is to use a brush to brush or an air gun to blow them off. These two methods have the problems of low processing efficiency and difficulty in removing small-sized waste materials embedded in the gaps of fine lines on the chip surface. Therefore, the technical field of processing waste materials on the chip surface needs a reliable and effective method for removing movable waste materials on the chip surface. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a method for removing movable excess matter on the surface of a chip.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] A method for removing movable excess matter on a chip surface comprises the following steps:

[0006] S100, preparing a soaking solution;

[0007] S200, using a detection tool to determine the location of excess material on the chip surface;

[0008] S300, immersing the chip in the immersion solution, and using a soft-headed brush to sweep back and forth multiple times over the excess material distribution area on the chip surface;

[0009] S400, shaking the chip in the solution for several times and then taking it out;

[0010] S500, use a high-pressure air gun to blow dry the chip surface before the soaking solution remaining on the chip surface evaporates;

[0011] S600, using a detection tool to check the residual waste on the chip surface, and determine whether it meets the preset quality level requirements; if not, return to step S200 until the quality level requirements are met.

[0012] Furthermore, in the step S100, when preparing the soaking solution, a container with a clean inner wall is selected, and the inner wall of the container is repeatedly wiped multiple times with a dust-free cloth moistened with anhydrous ethanol, and then anhydrous ethanol is poured into the container as the soaking solution.

[0013] Furthermore, the container is a glass beaker or a stainless steel cup.

[0014] Furthermore, in the steps S200 and S600, the detection tool used is a high-power microscope that meets the requirements for observing μm-level chips.

[0015] Furthermore, in the step S200, the method for determining the location of the excess material on the chip surface is: using a high-power microscope to observe the distribution of the excess material on the chip surface and drawing a schematic diagram to mark the excess material distribution area, or using an electronic device to take a photo to record the excess material distribution area.

[0016] Furthermore, in the step S300, a soft-headed brush is used to sweep the excess matter distribution area on the chip surface back and forth 8 to 12 times to remove movable excess matter in the excess matter distribution area.

[0017] Furthermore, the soft-head brush comprises a handle and a brush head arranged at one end of the handle, and the brush head is made of fine and soft material.

[0018] Furthermore, when using the soft-headed brush to clean the movable excess materials on the chip surface, the angle between the handle of the soft-headed brush and the chip surface is maintained at 30° to 60°.

[0019] Furthermore, in the step S400, the chip is repeatedly shaken in the soaking solution for 3 to 5 seconds and then taken out from the soaking solution.

[0020] Furthermore, in the step S500, after the chip is taken out of the immersion solution, the residual immersion solution is blown away with a high-pressure air gun within 3 seconds. During the blowing, the air pressure and blowing distance of the high-pressure air gun are controlled so that the immersion solution remaining on the chip surface forms droplets and is blown away from the chip surface in the form of splashes.

[0021] The present invention provides a method for removing movable excess matter on the chip surface. After confirming the position and area of ​​the movable excess matter through a high-power microscope, a soft-headed brush is first used to brush away most of the movable excess matter on the chip surface in an immersion solution, and then a high-pressure air gun is used to quickly blow dry the residual droplets on the chip surface to remove the small-sized movable excess matter on the chip surface that is difficult to remove with a brush. The combination of the two treatment methods can quickly and effectively remove the movable excess matter on the chip surface, thereby improving the chip surface quality. At the same time, the method of the present invention can also improve the processing efficiency of removing the movable excess matter on the chip surface to a certain extent because of its simple and efficient operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0023] Figure 1 The flowchart is a method for removing movable excess matter on a chip surface according to an embodiment of the present invention.

[0024] Figure 2 It is a schematic diagram of the structure of a soft-head brush.

[0025] Figure 3 Schematic diagram of using a high-pressure air gun to blow dry the chip surface.

[0026] The accompanying drawings in the specification are numeraled as follows:

[0027] Tube shell-1; chip-2; excess matter-3; residual soaking solution-4; high-pressure air gun nozzle-5; high-pressure air flow-6; splashing droplets containing excess matter-7; soft-headed brush-10; handle-11; brush head-12. DETAILED DESCRIPTION

[0028] The following describes the implementation methods of the present invention through specific examples. The illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention. The following embodiments and features in the embodiments may be combined with each other without conflict.

[0029] See also Figure 1 , Figure 1 This is a flow chart of an embodiment of a method for removing movable excess matter on a chip surface according to the present invention. The method for removing movable excess matter on a chip surface according to this embodiment comprises the following steps:

[0030] Prepare in advance the relevant tools for processing and detecting the movable excess material 3, such as: a high-power microscope, a soft-head brush 10, a high-pressure air gun, etc.

[0031] S100, prepare a soaking solution. The prepared soaking solution needs to be wettable with the movable excess material 3 on the surface of the chip 2, so that the movable excess material 3 swept away by the brush can be wrapped and taken away from the surface of the chip 2. In this embodiment, anhydrous ethanol is used as the soaking solution. When preparing the soaking solution, use anhydrous ethanol to wet a clean cotton cloth and repeatedly wipe the inner wall of the beaker for multiple times (for example: 5 times). After wiping, pour an appropriate amount of anhydrous ethanol as the soaking solution. The container can be a glass beaker or a stainless steel cup, and the purity of the anhydrous ethanol exceeds 99%. The soaking solution level in the container can reach a position close to the mouth of the cup to facilitate subsequent manual operations.

[0032] S200, using a detection tool to determine the location of the excess 3 on the surface of the chip 2. The detection tool can be a high-power microscope that meets the requirements for observing the μm-level chip 2, so that the inspector can accurately identify the location of the excess 3. The method for determining the location of the excess 3 on the surface of the chip 2 is: using a high-power microscope to observe the distribution of the excess 3 on the surface of the chip 2 and record the distribution area of ​​the excess 3. When recording the distribution area of ​​the excess 3, you can use paper and pen to draw a schematic diagram of the chip 2, circle the corresponding position of the schematic diagram to record the distribution area of ​​the excess 3, or use an electronic device to take a photo and record.

[0033] S300, immerse the chip 2 in the soaking solution. Since the chip 2 is generally carried by the circuit tube shell 1, the chip 2 is completely immersed in the soaking solution by taking the circuit tube shell 1 carrying the chip 2. Then use a soft-headed brush 10 to sweep back and forth for many times in the distribution area of ​​the excess material 3 on the surface of the chip 2. The entire cleaning process is carried out in an anhydrous ethanol soaking environment, and the brush sweeping back and forth should be gentle and slow. In this embodiment, the soft-headed brush 10 is used to sweep back and forth the distribution area of ​​the excess material 3 on the surface of the chip 2 8 to 12 times, preferably 10 times, to sweep away the movable excess material 3 in the distribution area of ​​the excess material 3.

[0034] See also Figure 2 The soft-headed brush 10 includes a handle 11 and a brush head 12 arranged at one end of the handle 11. The brush head 12 is made of fine and soft material, so that the movable excess material 3 on the surface of the chip 2 can be swept away, and the brush head 12 is not easy to scratch the surface of the chip 2. In this embodiment, the brush head 12 is made of fiber hair, and the fiber hair of the brush head 12 is dense and solid. The handle 11 is of appropriate length, which is convenient for the inspector to hold and operate conveniently. At the same time, in the process of removing the excess material 3, the fiber hair is prevented from falling off or scratching the chip 2, thereby introducing new foreign matter. In the process of using the soft-headed brush 10 to sweep the movable excess material 3 on the surface of the chip 2, the angle between the handle 11 of the soft-headed brush 10 and the surface of the chip 2 is maintained at 30° to 60°, preferably maintained at 45°.

[0035] S400, the chip 2 is shaken in the solution for several times and then taken out. Generally, the chip 2 is shaken repeatedly in the immersion solution for 3 to 5 seconds before being taken out from the immersion solution. In this embodiment, the chip 2 is shaken back and forth in the solution for 6 times with a large amplitude (for about 3 to 5 seconds) to ensure that the excess material 3 brushed away by the brush is away from the surface of the chip 2.

[0036] S500, use a high-pressure air gun to blow dry the surface of the chip 2 before the residual soaking solution 4 on the surface of the chip 2 evaporates. Generally, it is necessary to use a high-pressure air gun to blow off the residual soaking solution 4 within 3S after the chip 2 is taken out of the soaking solution. Generally, a high-pressure air gun with air pressure adjustment function is used to meet the requirements of various airflow pressures in various application scenarios.

[0037] See also Figure 3 When using a high-pressure air gun to blow off the soaking solution 4 remaining on the surface of the chip 2, it is necessary to adjust the air pressure of the high-pressure air gun and the distance between the air gun nozzle and the surface of the chip 2 to ensure that the soaking solution 4 remaining on the surface of the chip 2 forms droplets under appropriate pressure and blowing distance and is blown away from the surface of the chip 2 in the form of splashes; due to the wettability and tension of the soaking solution, the small-sized movable excess 3 remaining in the fine line gaps on the surface of the chip 2 will float in the soaking solution 4 droplets remaining on the surface of the chip 2; the droplets will splash and take away the excess 3 in the droplets. Of course, when blowing, the angle between the high-pressure air gun nozzle 5 and the surface of the chip 2 will also be adjusted according to the actual situation to better blow off the soaking solution 4 remaining on the surface of the chip 2.

[0038] S600, using a detection tool (i.e., a high-power microscope that meets the requirements for observing the μm-level chip 2) to check the residual situation of the excess material 3 on the surface of the chip 2, and determine whether it meets the preset quality level requirements. For example, the relevant requirements of GJB548 can be used as the quality level requirements for the excess material 3 on the surface of the chip 2. If it does not meet the preset quality level requirements, return to step S200 and remove the movable excess material 3 on the surface of the chip 2 again until the quality level requirements are met.

[0039] Compared with the prior art, after adopting the method of this embodiment, the inspector uses a microscope capable of observing the chip 2 at the μm level to confirm the exact position of the movable excess 3 of the chip 2, and the effect of accurate removal can be achieved; the configured soaking solution for cleaning the chip 2 can effectively absorb the movable excess 3 swept from the surface of the chip 2 by the soft-headed brush 10, and the soft-headed brush 10 itself is not easy to be attached with the excess 3 when brushing in the soaking solution, and there is no need to frequently replace the brush, which is low in cost and high in practicality. Using the above method, the position of the movable excess 3 on the surface of the chip 2 is first confirmed by a high-power microscope, and then the movable excess 3 on the surface of the chip 2 is removed by soaking in the cleaning solution, sweeping with the soft-headed brush 10, and blowing with high-pressure gas in sequence. By combining multiple processing methods, the movable excess 3 on the surface of the chip 2 can be quickly and effectively processed.

[0040] The above embodiments only express the preferred implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for removing movable excess material from a chip surface, characterized in that: The following steps are involved: S100, preparing a soaking solution; S200, using a detection tool to determine the location of excess material on the chip surface; S300, immersing the chip in the immersion solution, and using a soft-headed brush to sweep back and forth multiple times over the excess material distribution area on the chip surface; S400, shaking the chip in the solution for several times and then taking it out; S500, use a high-pressure air gun to blow dry the chip surface before the soaking solution remaining on the chip surface evaporates; S600, using a detection tool to check the residual waste on the chip surface, and determine whether it meets the preset quality level requirements; if not, return to step S200 until the quality level requirements are met.

2. The method for removing movable excess matter on the chip surface as claimed in claim 1, characterized in that: In the step S100, when preparing the soaking solution, a container with a clean inner wall is selected, and the inner wall of the container is repeatedly wiped multiple times with a dust-free cloth moistened with anhydrous ethanol, and then anhydrous ethanol is poured into the container as the soaking solution.

3. The method for removing movable excess matter on the chip surface as claimed in claim 2, characterized in that: The container is a glass beaker or a stainless steel cup.

4. The method for removing movable excess matter on the chip surface as claimed in claim 1, characterized in that: In the steps S200 and S600, the detection tool used is a high-power microscope that meets the requirements for observing μm-level chips.

5. The method for removing movable excess matter on the chip surface as claimed in claim 4, characterized in that: In the step S200, the method for determining the location of the excess on the chip surface is: using a high-power microscope to observe the distribution of the excess on the chip surface and drawing a schematic diagram to mark the excess distribution area, or using an electronic device to take a photo to record the excess distribution area.

6. The method for removing movable excess matter from the chip surface according to any one of claims 1 to 5, characterized in that: In the step S300, a soft-headed brush is used to sweep the excess matter distribution area on the chip surface back and forth 8 to 12 times to remove the movable excess matter in the excess matter distribution area.

7. The method for removing movable excess matter on the chip surface as claimed in claim 6, characterized in that: The soft-head brush comprises a handle and a brush head arranged at one end of the handle, and the brush head is made of fine and soft material.

8. The method for removing movable excess matter on the chip surface as claimed in claim 7, characterized in that: When using a soft-headed brush to sweep away the movable excess material on the chip surface, the angle between the handle of the soft-headed brush and the chip surface is maintained at 30° to 60°.

9. The method for removing movable excess matter from the chip surface according to any one of claims 1 to 5, characterized in that: In the step S400, the chip is repeatedly shaken in the soaking solution for 3 to 5 seconds and then taken out from the soaking solution.

10. The method for removing movable excess matter on the chip surface according to any one of claims 1 to 5, characterized in that: In the step S500, after the chip is taken out of the soaking solution, the residual soaking solution is blown away within 3 seconds using a high-pressure air gun. During the blowing, the air pressure and blowing distance of the high-pressure air gun are controlled so that the soaking solution remaining on the chip surface forms droplets and is blown away from the chip surface in the form of splashes.

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