A silicone pressure-sensitive adhesive degumming solution and its application process

Abstract

The present invention provides a kind of organosilicon pressure-sensitive adhesive debonding liquid and its application process, the debonding liquid comprises 8-15% of polyol, 3-7% of fatty amine, 4-20% of cosolvent, and the balance is solvent, wherein the cosolvent is a compound of phosphate and ketone; the present invention helps to accelerate the stripping rate of organosilicon pressure-sensitive adhesive by adding fatty amine to the debonding liquid; the phosphate group and ketone group in the cosolvent cooperate with each other, combine with the active end groups at both ends of the siloxane adhesive in the organosilicon pressure-sensitive adhesive, promote the removal of organosilicon pressure-sensitive adhesive, the fatty amine and the cosolvent form a "peel and pull" effect on the organosilicon pressure-sensitive adhesive, so that the stubborn residual adhesive falls off and dissolves in the solvent, and the polyol reduces the surface tension of the solution, so that the surface of the sample remains flat and smooth. The debonding liquid of the present invention has a reasonable formula, is not easy to volatilize, can completely remove the organosilicon pressure-sensitive adhesive residue, and makes the sample after debonding have good roughness.

Description

Technical Field

[0001] The present invention relates to the field of cleaning agents for semiconductor industry, and in particular to an organic silicon pressure-sensitive adhesive debonding liquid and an application process thereof. Background Art

[0002] Driven by applications such as high-performance computing, data centers, in-vehicle displays, and business conferencing, the demand for displays capable of displaying large amounts of information across various industries is increasing. The semiconductor display sector is rapidly developing and attracting significant attention. Micro-LEDs (micro-LEDs) are a type of display technology that utilizes traditional LEDs by miniaturizing them to form arrays with micron-level spacing, achieving ultra-high resolution. Compared to traditional liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs), micro-LED displays offer advantages such as long lifespan, high brightness, a thin and lightweight design, low power consumption, and high pixel density. They represent the third generation of displays, characterized by high fidelity, interactivity, and personalized displays.

[0003] Currently, Micro-LED is limited by the technology of mass transfer of lamp beads, and most displays are small in size. Glass front and back wiring screen splicing technology is one of the solutions. Silicone pressure-sensitive adhesive protective film will be used for wiring on the front and back of the glass. Silicone pressure-sensitive adhesive protective film has strong adhesion. After the substrate undergoes multiple high-temperature baking and vacuum processes, a large amount of silicone pressure-sensitive adhesive will remain after the protective film is torn off, and it is stubborn and difficult to remove, affecting the electrical performance of the substrate and subsequent processes.

[0004] While the preparation and properties of silicone pressure-sensitive adhesives (PSAs) have been extensively and intensively studied, methods for removing residual silicone PSA residues are less explored. Therefore, it is crucial to provide a debonding solution that effectively removes residual silicone PSA residue from substrates without adversely affecting substrate properties. Summary of the Invention

[0005] The main purpose of the present invention is to overcome the deficiencies of the prior art and provide a silicone pressure-sensitive adhesive degumming liquid which is non-volatile, has a fast degumming rate and good degumming effect.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A silicone pressure-sensitive adhesive debonding solution comprises, by weight percentage, 8-15% of polyol, 3-7% of fatty amine, 4-20% of cosolvent, and the balance being solvent.

[0008] The polyol is one or more of ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and glycerol. The polyol reduces the surface tension of the solution and improves the wettability of the liquid medicine.

[0009] The fatty amine is at least one of ethylenediamine, isopropylamine, 1,4-butanediamine, tert-butylamine and 2-ethylhexylamine. The fatty amine can provide alkaline conditions for removing the organic silicone pressure-sensitive adhesive, promote the dissolution of the organic silicone pressure-sensitive adhesive on the substrate, and accelerate the peeling rate of the organic silicone pressure-sensitive adhesive.

[0010] The cosolvent is a mixture of a phosphate ester and a ketone, with the weight ratio of the phosphate ester to the ketone being 1:2-1:5; preferably, the weight ratio is 1:3. The synergistic effect of the phosphate ester and ketone mixture increases the surface activity of the substrate and accelerates the removal of the silicone pressure-sensitive adhesive.

[0011] Furthermore, the phosphate ester is at least one of trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, tricresyl phosphate, dimethyl phosphate, diethyl phosphate, dibutyl phosphate, di(2-ethylhexyl) phosphate, and tetraethylmethylene diphosphate.

[0012] Furthermore, the ketone is at least one of dicyclopropyl ketone, cyclopentyl ethyl ketone, and dicyclohexyl ketone.

[0013] Furthermore, the solvent is at least one of dimethyl sulfoxide, sulfolane, dimethyl sulfone, N,N-dimethylformamide, N-methylpiperazine, N-ethylpiperazine, diethyl sulfone, and tetramethylene sulfone, with dimethyl sulfoxide being more preferred. The organic solvent has good water solubility and can effectively dissolve the silicone pressure-sensitive adhesive, thereby facilitating its removal.

[0014] The degumming liquid of the present invention can fully spread and penetrate on the surface of the substrate; the fatty amine can provide alkaline conditions for removing the silicone pressure-sensitive adhesive, promote the dissolution of the silicone pressure-sensitive adhesive on the substrate, and accelerate the peeling rate of the silicone pressure-sensitive adhesive; the cosolvent of a compound of phosphate and ketone is used, wherein the phosphate group (O=P-ORx) and the ketone group (O=C-Ry) cooperate with each other to combine with the active end groups of the siloxane adhesive in the silicone pressure-sensitive adhesive to promote the removal of the silicone pressure-sensitive adhesive. The fatty amine and the cosolvent form a "peeling and pulling" effect on the silicone pressure-sensitive adhesive, causing stubborn residual adhesive to fall off and dissolve in the solvent; the polyol organic compound can improve the wettability of the liquid, can clean surface particles and residues, keep the sample surface free of residue after degumming, and have good roughness; the water-soluble organic solvent promotes the dissolution and removal of the residual film. The synergistic effect of all components of the present invention accelerates the degumming speed and enhances the degumming effect.

[0015] The present invention also provides the use of the above-mentioned adhesive removal solution in removing the organic silicon pressure-sensitive adhesive remaining on the semiconductor sample after high-temperature curing.

[0016] Furthermore, the application process of the adhesive stripping solution in removing the organic silicon pressure-sensitive adhesive remaining on the semiconductor sample after high-temperature curing specifically includes the following steps:

[0017] S1: Pour the silicone pressure-sensitive adhesive remover solution into the remover tank, heat it up, and vertically place the sample to be removed from the silicone pressure-sensitive adhesive into the remover tank for soaking;

[0018] S2: After soaking for a certain period of time, first place the sample vertically in a cleaning tank filled with N-methylpyrrolidone and soak it at room temperature for 5-10 minutes, then place the sample vertically in deionized water for cleaning and drying;

[0019] S3: Observe the sample after debonding under a microscope to confirm whether there is any residual silicone pressure-sensitive adhesive and the roughness of the sample surface.

[0020] Furthermore, in S1, the soaking is pulling or ultrasonic soaking to obtain a better removal effect.

[0021] Furthermore, in S1, the degumming solution is immersed in a temperature of 50-80° C. for 5-10 minutes.

[0022] Further preferably, the immersion temperature of the degumming solution is 60-70°C.

[0023] Furthermore, in S2, N-methylpyrrolidone is first used to clean the degumming solution remaining on the surface of the sample, and then deionized water is used for cleaning, thereby achieving a thorough cleaning effect.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The degumming solution of the present invention enhances its permeability and solubility through the synergistic effect of fatty amines, phosphate groups (O=P-ORx), and ketone groups (O=C-Ry), thereby stripping the silicone pressure-sensitive adhesive layer remaining on the sample after high-temperature curing, causing the stubborn residual adhesive to fall off and dissolve into the solution. The addition of polyol removes surface particles and residues, leaving the sample surface clean and with good roughness after degumming.

[0026] 2. By adjusting the content of each component in the degumming liquid, the degumming liquid prepared in the present invention can efficiently and quickly strip silicone pressure-sensitive adhesive, significantly shortening the degumming time, and the surface of the substrate after stripping is smooth and free of residue. The degumming liquid of the present invention is particularly capable of removing silicone pressure-sensitive adhesive remaining on samples after multiple high-temperature baking and vacuum processes. DETAILED DESCRIPTION

[0027] In order to better understand the present invention, the present invention is further described in detail below in conjunction with tables and examples, but the scope of protection claimed in the present invention is not limited to the following examples.

[0028] The degumming solution of the present invention can be obtained by simply mixing the components described in the following examples and comparative examples.

[0029] Table 1 Components and contents of the degumming solutions of Examples 1-14 and Comparative Examples 1-6

[0030]

[0031] The present invention also provides a process for applying the above-mentioned adhesive stripping solution to remove the organic silicon pressure-sensitive adhesive remaining on a semiconductor sample after high-temperature curing, which specifically comprises the following steps:

[0032] S1: Pour the silicone pressure-sensitive adhesive remover solution into the remover tank, heat it to 70°C, and vertically place the sample to be removed from the silicone pressure-sensitive adhesive into the remover tank for ultrasonic immersion.

[0033] S2: After soaking for a certain period of time, the sample is placed vertically in a cleaning tank filled with N-methylpyrrolidone and allowed to soak at room temperature for 5 minutes. The sample is then placed vertically in deionized water for cleaning and drying.

[0034] S3: Observe the sample after debonding under an optical microscope to confirm whether there is any residual silicone pressure-sensitive adhesive. Observe the sample after debonding under an atomic force microscope to confirm the surface roughness after debonding.

[0035] S4: Based on the removal effect, if the residual glue is confirmed to be completely removed under an optical microscope, stop immersing and record the immersion time and surface roughness; if the residual glue is confirmed to be not completely removed under an optical microscope, repeat steps S1-S3 and increase the immersion time of the glue removal solution by 5 minutes each time. The immersion time shall not exceed 40 minutes until the residual glue is completely removed or stop at 40 minutes, and record the immersion time and surface roughness.

[0036] Performance testing:

[0037] Samples (3 x 3 cm) of the silicone pressure-sensitive adhesive to be removed were immersed in the silicone pressure-sensitive adhesive stripping solutions described in the Examples and Comparative Examples, respectively, at 70°C for 5 minutes. The soaking time was increased by 5 minutes each time, depending on the removal effect, up to a maximum of 40 minutes, until complete removal or until 40 minutes had passed. The soaking time was recorded. After stripping was complete, the samples were rinsed with N-methylpyrrolidone and then with deionized water, and dried. The removal effect of the stripping solution was observed under a microscope. The test results are shown in Table 2.

[0038] Evaluation criteria for silicone pressure-sensitive adhesive removal:

[0039] Excellent: The surface after degumming is smooth and has no residue;

[0040] Good: There is no residue on the surface after degumming, but there are slight unevenness;

[0041] Poor: There is no residue on the surface after degumming, but there are obvious unevenness or residue on the surface.

[0042] Table 2 Removal of silicone pressure-sensitive adhesive from samples in Examples and Comparative Examples

[0043]

[0044] According to the results of the above examples and comparative examples, it can be seen that the degumming solutions provided in Examples 1-14 can all completely remove the silicone pressure-sensitive adhesive on the surface of the sample within 5 minutes, and keep the surface of the sample flat and smooth. Compared with Example 1, the example shows that adding a polyol to the degumming solution can keep the surface of the sample flat and smooth; compared with Example 2 and Comparative Examples 4-6, it is shown that adding a fatty amine or a cosolvent to the degumming solution can quickly and efficiently remove the silicone pressure-sensitive adhesive; compared with Example 3, it is shown that adding a certain amount of fatty amine to the degumming solution can achieve an efficient and rapid degumming effect. It can be seen that the three components in the degumming solution of the present invention have a synergistic effect on the removal of the silicone pressure-sensitive adhesive remaining on the sample after multiple high-temperature baking and vacuum processes.

[0045] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention shall be the technical solutions set forth in the claims, including equivalent alternatives to the technical features of the technical solutions set forth in the claims. In other words, equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A silicone pressure-sensitive adhesive remover, characterized in that: The invention comprises the following components in percentage by weight: 8-15% of polyol, 3-7% of fatty amine, 4-20% of cosolvent, and the balance of solvent; The polyol is at least one of 1,2-propylene glycol, 1,4-butanediol or 1,6-hexanediol; The fatty amine is at least one of isopropylamine, 1,4-butanediamine or 2-ethylhexylamine; The cosolvent is a compound of a phosphate ester and a ketone, wherein the weight ratio of the phosphate ester to the ketone is 1:3; the phosphate ester is at least one of triethyl phosphate, tricresyl phosphate, or di(2-ethylhexyl) phosphate, and the ketone is at least one of dicyclopropyl ketone, cyclopentyl ethyl ketone, or dicyclohexyl ketone; The solvent is dimethyl sulfoxide.

2. Use of the organic silicone pressure-sensitive adhesive remover according to claim 1 in removing organic silicone pressure-sensitive adhesive remaining on semiconductor samples after high-temperature curing.

3. The use according to claim 2, characterized in that The process of the application comprises the following steps: S1: Pour the silicone pressure-sensitive adhesive remover solution into the remover tank, heat it up, and vertically place the sample to be removed from the silicone pressure-sensitive adhesive into the remover tank for soaking; S2: After soaking, place the sample vertically in a cleaning tank filled with N-methylpyrrolidone and soak it at room temperature for 5-10 minutes. Then, place the sample vertically in deionized water for cleaning and drying. S3: Observe the sample after debonding under a microscope to confirm whether there is any glue residue and the roughness of the sample surface.

4. The use according to claim 3, characterized in that In S1, the degumming solution is immersed in the solution at a temperature of 50-80° C. for 5-10 minutes.

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