Method for removing residue on surface of silicon wafer

Abstract

The present application provides a kind of silicon wafer surface residual glue removal method, steps include: the silicon wafer with residual glue is placed in piece cavity and heated to soften residual glue;After softening is completed, remove piece cavity, and remove residual glue within a set time again.The present application provides a kind of silicon wafer surface residual glue removal method, by placing the silicon wafer with residual glue in the closed environment with automatic heating to heat and soften, to achieve the purpose of removing residual glue in batches, residual glue removal speed is fast and removal effect is good, no glue printing residual, especially when the heating temperature is 100-150 DEG C and within 5min, the glue removal effect is best.

Description

Technical Field

[0001] This invention belongs to the technical field of silicon wafer debonding equipment, and in particular relates to a method for removing residual adhesive from the surface of silicon wafers. Background Technology

[0002] During the debonding process, some adhesive residue may remain. Current technologies use hot air guns for intermittent localized heating, but this method requires multiple heating cycles to confirm successful removal, resulting in low efficiency and a high rework rate. Each time the hot air gun is used, the silicon wafer surface temperature drops rapidly, leaving adhesive residue at the original location, leading to incomplete removal. Furthermore, these hot air guns are difficult to stabilize at the heating temperature and are greatly affected by the working environment, resulting in inconsistent debonding quality. Summary of the Invention

[0003] This invention provides a method for removing residual adhesive from the surface of silicon wafers, which solves the technical problem that existing adhesive removal methods result in residual adhesive remaining on the surface of silicon wafers and have low adhesive removal efficiency.

[0004] To solve at least one of the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A method for removing residual adhesive from a silicon wafer surface, comprising the following steps:

[0006] The silicon wafer with residual adhesive is placed in the wafer cavity and heated to soften the adhesive.

[0007] After softening, remove the tablet from the cavity and remove any remaining adhesive within the set time.

[0008] Further, the silicon wafer with residual adhesive is placed in the wafer cavity and heated, the step of which includes:

[0009] First, place the silicon wafer vertically on a fixed frame with the end with residual adhesive facing upwards and suspended in the air.

[0010] The fixing frame is placed inside the cavity and hot air is continuously introduced for heating. The heating temperature is 100-150℃ and the heating time is 3-15 minutes.

[0011] Furthermore, the heating temperature of the residual adhesive on the silicon wafer is 100°C.

[0012] Furthermore, each mounting bracket can hold several sets of silicon wafers, each set comprising several stacked silicon wafers.

[0013] Furthermore, adjacent groups of silicon wafers need to be spaced apart, with a spacing of not less than 50-100mm.

[0014] Furthermore, the silicon wafers in the same group are of the same type; and the number of silicon wafers in adjacent groups may be different.

[0015] Furthermore, the silicon wafer is de-adhesive-free within 7 minutes of being removed after heating.

[0016] Furthermore, the adhesive is removed from the silicon wafer within 5 minutes after heating is completed.

[0017] Furthermore, the silicon wafer is heated in the wafer cavity in an oven or baking oven.

[0018] Furthermore, during the heating process, the airflow in the oven or baking oven is heated by the heating tubes through the air cavity set inside it before entering the wafer cavity. The air cavity can also move vertically up and down along the height direction of the wafer cavity to adjust the direction of the hot airflow towards the adhesive side of the silicon wafer.

[0019] Compared with existing technologies, the silicon wafer surface residual adhesive removal method designed in this invention removes residual adhesive in batches by placing the silicon wafer with residual adhesive in a sealed environment with automatic heating to soften it. The residual adhesive removal speed is fast and the removal effect is good, with no adhesive residue. The adhesive removal effect is best when the heating temperature is 100-150℃ and within 5 minutes of removal. Attached Figure Description

[0020] Figure 1 This is a flowchart of a method for removing residual adhesive from the surface of a silicon wafer according to an embodiment of the present invention;

[0021] Figure 2 This is a structural diagram of a silicon wafer surface residual adhesive removal device according to an embodiment of the present invention;

[0022] Figure 3 This is a structural diagram of a fixing frame according to an embodiment of the present invention.

[0023] In the picture:

[0024] 10. Box body; 20. Fixture; 21. Sheet placement area

[0025] 22, spacer bar 30, heating element 40, air cavity Detailed Implementation

[0026] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0027] This embodiment proposes a method for removing residual adhesive from the surface of silicon wafers, such as... Figure 1 As shown, the steps include:

[0028] The silicon wafer with residual adhesive is placed in the wafer cavity and heated to soften the adhesive.

[0029] Specifically, the silicon wafer with residual adhesive is first placed vertically on a mounting frame 10, with the end containing the adhesive facing upwards and suspended in the air. The wafer cavity used for heating the silicon wafer can be a chamber 10 similar to an oven or drying oven, with the structure as follows: Figure 2 As shown, the fixing frame 20 allows silicon wafers with residual adhesive to be placed vertically in batches within a sealed box 10 and continuously heated by hot air blown into the wafer cavity. This softens the residual adhesive on the silicon wafers before they are removed for adhesive removal. This method is not only convenient to operate and allows for batch heating and softening of silicon wafers with residual adhesive, but also ensures that the heating temperature is sustainable and stable, laying the foundation for rapid and clean removal of residual adhesive in the future.

[0030] The housing 10 has a cavity for placing the mounting bracket 20 and an air cavity 40 for providing a heat source. The air cavity 40 is connected to an external air compressor and a heating pipe 30 for heating the airflow. The hot airflow blowing out of the air cavity 40 can be adjusted up and down along the height of the silicon wafer to adjust the direction of the hot airflow towards the adhesive surface of the silicon wafer. The cavity in the housing 10 is arranged along its length. To facilitate the support of the mounting bracket 20, both ends of the housing 10 are provided with doors, allowing the mounting bracket 20 to be placed open. A base support for the mounting bracket 20 is provided on the lower end face of the cavity. The outer sides of the base support are all right-angled structures with arcs, and a boss with the same structure as the outer sides is provided on its upper end face. The purpose of the boss is to prevent the mounting bracket 20 from being positioned and to provide a fixing function. The thickness of the base support should not be too high, and should be 5-15mm, allowing the mounting bracket 20 to be suspended in the air.

[0031] Furthermore, the opposing surfaces of the base supports arranged along the length of the fixing frame 20 have a V-shaped structure. Preferably, the included angle of the V-shaped structure on the opposing side of the base supports is not less than 100° and not greater than 175°. This structure not only facilitates increasing the contact area between the fixing frame 20 and the base supports, but also minimizes the heat-receiving area occupied by the base supports, thereby minimizing the heat consumption of the base supports while ensuring the stability of the fixing frame 20.

[0032] The fixing frame 20 is placed above each set of oppositely arranged bases and secured by protrusions on the bases. The lower end face of all fixing frames 20 is made of several slats spliced ​​together at intervals, and its sides are also connected in a ring of slats at intervals, in order to facilitate the flow of hot air.

[0033] Furthermore, each housing 10 can hold a plurality of mounting brackets 20, and each mounting bracket 20 can be provided with a plurality of wafer placement areas 21 for placing silicon wafers. The structure of the mounting bracket 20 is as follows: Figure 3As shown, the silicon wafer with residual adhesive is placed upright in the wafer placement area 21 with one end facing upwards, and the height of the fixing frame 20 is lower than the height of the silicon wafer. The purpose is to increase the contact area between the residual adhesive and the hot air. If the silicon wafer with residual adhesive is placed horizontally or vertically downwards, there is a risk that the residual adhesive will remain in the fixing frame 20, which will not only be inconvenient to clean, but will also increase the additional processing cost.

[0034] In each wafer placement area 21, all silicon wafers are arranged side by side along the width of the wafer placement area 21, and the end with residual adhesive is vertically suspended upwards. The heating temperature in the housing 10 can directly heat and soften the suspended residual adhesive.

[0035] Meanwhile, to increase the quantity and variety of silicon wafers that can be placed, adjacent groups of silicon wafers need to be spaced apart, with a spacing of no less than 50-100mm. Specifically, a set of spacers 22 is provided between each pair of adjacent groups of silicon wafers placed vertically in the wafer placement area 21. Each spacer 22 is located close to the inner wall of the mounting bracket 20, and each spacer 22 is at least 50-100mm thick. The gap between adjacent spacers 22 is less than half the lateral width of the silicon wafer, which not only improves the efficiency of hot airflow but also saves production costs and enhances the safety of silicon wafer placement.

[0036] Furthermore, the silicon wafers in the same group are of the same type, and the number of silicon wafers in adjacent groups can be different. That is, in the same mounting bracket 20, the length of the wafer placement area 21 is the number of vertically stacked silicon wafers, and this length can be different for each group. Of course, if actual needs require, the number of silicon wafers placed can also be the same. If it is necessary to place silicon wafers from different batches, the placement position of the spacer 22 can be adjusted to change the length of the wafer placement area 21, thereby distinguishing the placement position of different batches of silicon wafers according to the different lengths. The width of each group of mounting brackets 20 is the same, and the widths of multiple groups of mounting brackets 20 can be the same or different. The width of the mounting brackets 20 can be designed based on the width of different types of silicon wafers, and there are no specific restrictions here.

[0037] Heating tube 30 is fixed to the bottom of housing 10 and located below the cavity. Air cavity 40 is located on the side of housing 10 along its length, with the air outlet in air cavity 40 positioned diagonally above the silicon wafer. The purpose is to blow hot air onto the residual adhesive on the silicon wafer at an angle. Heating tube 30 heats the airflow in air cavity 40, ensuring that the airflow entering the wafer cavity is hot air at a certain temperature. This hot airflow heats the residual adhesive, allowing the temperature in the cavity to be sustained and constant. The combination of heating tube 30 and air cavity 40 avoids the instability and discontinuity of existing hot air guns. It provides stable heating, a wide adhesive removal area, faster batch cleaning, and leaves no residue after removal, eliminating the need for rework. The removal effect is excellent and highly efficient, unlike existing hot air guns which leave adhesive residue after removal.

[0038] The air cavities 40 are set on both sides of the width direction of the housing 10. All air cavities 40 blow air towards the silicon wafer side along the length direction of the cavity. The fan blades can be freely adjusted to adjust the air volume, air speed and angle, in order to adjust the flow direction and flow rate of the heating airflow.

[0039] During operation, silicon wafers with residual adhesive are placed vertically in the placement area 21 of the fixing frame 20 beforehand. After the silicon wafers are placed, the fixing frame 20 is placed in the housing 10 and supported and fixed on the base. The heating tube 30 and the air chamber 40 are then turned on to control the temperature, flow rate, and direction of the hot airflow. The residual adhesive on the silicon wafers is heated in the housing 10 at a certain temperature for a certain time, wherein the heating temperature is 100-150℃ and the heating time is 3-15 minutes. Preferably, the heating temperature of the residual adhesive on the silicon wafers is 100℃, and the heating is carried out at 100℃ for 3-15 minutes.

[0040] After softening is complete, remove the softened silicon wafer and the retainer together from the wafer cavity, and then remove the residual adhesive within a set time.

[0041] Specifically, after the residual adhesive on the silicon wafer has been completely softened by heating, the furnace is shut down and the fixing bracket 20 is directly removed from the housing 10. After removing the silicon wafer, the residual adhesive can be peeled off with gloved hands within 7 minutes. Preferably, the residual adhesive is removed within 5 minutes after the silicon wafer is removed from the furnace.

[0042] Using the removal method in this embodiment, the adhesive was removed by heating at 100℃ for 3-15 minutes and then using gloves with gloves on at different time intervals. The heating time was 3 minutes, 5 minutes, 8 minutes and 15 minutes. After removing the silicon wafer, the adhesive was removed within 0 minutes, 2 minutes, 5 minutes, 7 minutes, 10 minutes and more than 10 minutes. The difficulty of removing the adhesive is shown in Table 1.

[0043] Table 1. Difficulty of removing adhesive at different heating times and different time intervals.

[0044]

[0045]

[0046] As can be seen from the above, when the temperature is 100℃ and the heating time is 5-15 minutes, the residual adhesive is easier to remove within 5 minutes after removal.

[0047] It is known that the method for removing residual adhesive from the surface of silicon wafers designed in this invention involves placing the silicon wafers with residual adhesive in an environment with automatic heating to soften them, thereby achieving the purpose of removing the residual adhesive in batches. The method has a fast removal speed and good removal effect, with no adhesive residue. The removal effect is best when the heating temperature is 100-150℃ and the removal time is within 5 minutes.

[0048] The embodiments of the present invention have been described in detail above. These descriptions are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A method for removing residual adhesive from a silicon wafer surface, characterized in that the steps include... include: The silicon wafer with residual adhesive is placed vertically on a fixed frame with the end with residual adhesive facing upwards and suspended in the air. It is then placed in the wafer cavity and heated to soften the residual adhesive. Hot air is continuously introduced into the cavity for heating at a temperature of 100-150°C for 3-15 minutes. After softening, the tablet is removed from the cavity, and any residual adhesive is removed within 5 minutes of removal. The heating of the silicon wafer in the wafer cavity is performed in an oven or baking oven, the oven or baking oven structure including: The box body has a cavity for placing the fixing frame. A base support for the fixing frame is provided in the cavity. The outer sides of the base support are all right-angled structures with arcs, and a boss with the same structure as the outer sides is provided on its upper surface. The mounting brackets are positioned above each set of opposing bases and secured by protrusions on the bases. The lower surfaces of all the mounting brackets are formed by splicing several spaced slats, and their sides are also formed by connecting spaced slats. Several mounting brackets are placed in each housing, and each mounting bracket has multiple wafer placement areas. The height of the mounting bracket is lower than the height of the silicon wafer. A set of spacers is provided between each pair of adjacent sets of silicon wafers, and each spacer is located near the inner wall of the mounting bracket. The thickness of each spacer is not less than 50-100mm, and the gap between adjacent spacers is less than half the lateral width of the silicon wafer. A heating element is fixed to the bottom of the housing and located below the cavity; The base allows the fixing frame to be suspended in the air; The opposing surfaces of the base, which are arranged opposite each other along the length of the fixing frame, are V-shaped structures, and the included angle of the V-shaped structure on the opposing side of the base is not less than 100° and not greater than 175°.

2. The method for removing residual adhesive from a silicon wafer surface according to claim 1, characterized in that, The heating temperature for the residual adhesive on the silicon wafer is 100°C.

3. A method for removing residual adhesive from a silicon wafer surface according to claim 1 or 2, characterized in that, Each mounting bracket holds several sets of silicon wafers, and each set includes several stacked silicon wafers.

4. The method for removing residual adhesive from a silicon wafer surface according to claim 3, characterized in that, The silicon wafers in two adjacent groups need to be spaced apart, and the spacing between them should not be less than 50-100mm.

5. The method for removing residual adhesive from a silicon wafer surface according to claim 4, characterized in that, The silicon wafers in the same group are of the same type; and the number of silicon wafers in adjacent groups are different.

6. A method for removing residual adhesive from a silicon wafer surface according to any one of claims 1-2 and 4-5, characterized in that, During the heating process, the airflow in the oven or baking oven is heated by the heating tube and then enters the wafer cavity through the air cavity set inside it. The air cavity moves vertically up and down along the height direction of the wafer cavity to adjust the direction of the hot airflow towards the adhesive side of the silicon wafer.

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