Photoresist stripping liquid as well as preparation method and application thereof
By using alkyl ketones, sulfoxides, and alkanolamines as organic solvents in combination with specific functional additives in the photoresist stripping solution, a multi-layer protective film is formed, which solves the problems of insufficient adhesive removal ability and poor high-temperature corrosion inhibition stability of traditional photoresist stripping solutions. This achieves efficient adhesive removal and low corrosion, meeting the requirements of green chemistry.
Patent Information
- Application Number
- CN202512024828.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-10
AI Technical Summary
Traditional photoresist stripping solutions have insufficient adhesive removal capabilities and poor high-temperature corrosion inhibition stability, leading to increased production costs and a greater risk of metal corrosion.
By using alkyl ketones, sulfoxides, and alkanolamines as organic solvents, combined with 2,4,6-tris(4-phenyl)-1,3,5-triazine derivatives and methyl 4-isopentenyloxycinnamate as functional additives, a multilayer protective film is formed, providing efficient degumming and high-temperature stability.
It achieves efficient removal of stubborn photoresist, reduces the risk of metal corrosion, improves production yield and process stability, and meets the requirements of green chemistry.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor manufacturing process technology, and in particular to a photoresist stripping solution, its preparation method, and its application. Background Technology
[0002] In current advanced semiconductor manufacturing processes, photoresist stripping solutions are crucial for ensuring chip surface cleanliness after pattern transfer. As chip structures become increasingly complex, traditional photoresist stripping solutions face significant challenges primarily in the following two aspects: First, there is insufficient resist removal capability. Photoresist that has undergone high-temperature etching or ion implantation processes is often difficult to remove due to denaturation and carbonization. To address this issue, the manufacturing process often adds a cleaning step, but this directly increases production costs. Simply increasing the alkalinity of the photoresist stripping solution to improve resist removal capability increases the risk of chip electrode corrosion. Second, there is poor high-temperature corrosion inhibition stability. To efficiently remove stubborn photoresist, the process needs to be carried out at high temperatures. However, most common traditional corrosion inhibitors gradually decompose and become inactive at high temperatures. With prolonged use, the risk of metal corrosion increases significantly, posing a lifespan risk to the photoresist stripping solution.
[0003] Therefore, in order to meet the current extreme requirements of chip manufacturing for process and yield, it is urgent to develop a photoresist stripping solution that can efficiently remove stubborn photoresist while providing long-lasting high-temperature corrosion inhibition. Summary of the Invention
[0004] The purpose of this invention is to provide a photoresist stripping solution, its preparation method, and its application, so as to solve the problems of insufficient adhesive removal ability and poor high-temperature corrosion inhibition stability of traditional photoresist stripping solutions in the prior art.
[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: The present invention provides a photoresist stripping solution, which comprises the following components in parts by weight: 20-75 parts of alkyl ketone organic solvent, 5-30 parts of sulfoxide organic solvent, 5-20 parts of alkanolamine organic solvent, and 0.1-5 parts of functional additives. The functional additives are 2,4,6-tris(4-phenyl)-1,3,5-triazine derivatives and methyl 4-isopentenyloxycinnamate.
[0006] Preferably, the structural formula of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative is shown in (I):
[0007] (I)
[0008] Wherein, R is selected from amino, methylamino, ethylamino, isopropylamino, hydroxyethylamino, amide, mercapto, sulfonic acid, or carboxyl.
[0009] Preferably, the mass ratio of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative to methyl 4-isopentenyloxycinnamate is 0.5~3:0.5~2.
[0010] Preferably, the alkane-ketone organic solvent comprises one or more of N-methylpyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, N-hydroxyethylpyrrolidone, N-dodecylpyrrolidone, N-cyclohexylpyrrolidone, 1-butyl-2-pyrrolidone, 1-benzyl-2-pyrrolidone, 1-cyclohexyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, and N-isopropylpyrrolidone.
[0011] Preferably, the sulfoxide organic solvent comprises one or more of dimethyl sulfoxide, diethyl sulfoxide, dipropyl sulfoxide, methyl phenyl sulfoxide, benzyl methyl sulfoxide, cyclohexyl sulfoxide, and sulfolane.
[0012] Preferably, the alkanolamine organic solvent comprises one or more of monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, and diethylene glycolamine.
[0013] The present invention also provides a method for preparing the above-mentioned photoresist stripping solution, comprising the following steps: weighing the above-mentioned raw materials respectively, then mixing alkyl ketone organic solvent, sulfoxide organic solvent and alkanolamine organic solvent and adding functional additives until completely dissolved to obtain photoresist stripping solution.
[0014] The present invention also provides an application of the above-described photoresist stripping solution in stripping photoresist from semiconductor chips.
[0015] Preferably, the step of stripping the photoresist from the semiconductor chip is as follows: immersing the semiconductor chip in a photoresist stripping solution and performing ultrasonic treatment to obtain the stripped semiconductor chip.
[0016] Preferably, the temperature of the photoresist stripping solution is 70~90℃; and the ultrasonic treatment time is 10~60min.
[0017] The beneficial effects of this invention are: In this invention, 2,4,6-tris(4-phenyl)-1,3,5-triazine derivatives serve as functional protective agents, forming a first chemical adsorption film on the metal surface through strong coordination. Methyl 4-isopentenyloxycinnamate fills the pores in the film through physical adsorption. Simultaneously, long hydrophobic chains form a second barrier on or between the triazine film. This dual protection mechanism, combined with the "multi-claw anchoring" principle, provides extremely robust and dense film formation corrosion inhibition and higher thermal stability in photoresist stripping solutions, achieving high cleanliness and low corrosion of the chip.
[0018] The methyl 4-isopentenyloxycinnamate used in this invention is a natural product extracted from plants, which meets the requirements of green chemistry and sustainable development in the semiconductor industry, giving the photoresist stripping solution environmentally friendly and sustainable potential.
[0019] The photoresist stripping solution of the present invention has the ability to quickly target and remove photoresist in chip cleaning and has multi-layer anti-corrosion capabilities, solving the problems of difficult cleaning of surface photoresist and low yield in chip production. Detailed Implementation
[0020] The present invention provides a photoresist stripping solution, which comprises the following components in parts by weight: 20-75 parts of alkyl ketone organic solvent, 5-30 parts of sulfoxide organic solvent, 5-20 parts of alkanolamine organic solvent, and 0.1-5 parts of functional additives. The functional additives are 2,4,6-tris(4-phenyl)-1,3,5-triazine derivatives and methyl 4-isopentenyloxycinnamate.
[0021] In this invention, the structural formula of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative is shown in (I):
[0022] (I)
[0023] Wherein, R is selected from amino, methylamino, ethylamino, isopropylamino, hydroxyethylamino, amide, mercapto, sulfonic acid, or carboxyl.
[0024] In this invention, the weight parts of the alkane-ketone organic solvent can be 30 parts, 40 parts, 45 parts, 50 parts, 56.5 parts, 60 parts, 62 parts, 66 parts, 68 parts, 70 parts, 71.5 parts, or 74 parts.
[0025] In this invention, the weight parts of the sulfoxide organic solvent can specifically be 8 parts, 10 parts, 15 parts, 18 parts, 20 parts, 24 parts, 26 parts, 28 parts, or 30 parts.
[0026] In this invention, the weight parts of the alkanolamine organic solvent can specifically be 8 parts, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, or 20 parts.
[0027] In this invention, the specific weight parts of the functional additive can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4.0 parts, 4.5 parts, or 5 parts.
[0028] In this invention, the mass ratio of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative and methyl 4-isopentenyloxycinnamate is 0.5~3:0.5~2, specifically 1:1, 1:0.5, 2:1, or 0.5:1.
[0029] In this invention, the cinnamic acid ester group of methyl 4-isoprenyloxycinnamate can adsorb onto the metal surface to form an initial protective film. The isopentenyloxy group, as an outwardly extending hydrophobic chain, constitutes a physical barrier, together forming a dense monomolecular protective layer that effectively blocks the attack of alkanolamines in the photoresist stripping solution on the metal electrode. Furthermore, the steric hindrance effect of methyl 4-isoprenyloxycinnamate can protect the chemical stability of the ester bond in a strongly alkaline environment, allowing it to maintain structural integrity and functionality even under harsh conditions, achieving a perfect balance between efficient corrosion inhibition and system compatibility.
[0030] In this invention, the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative has a triple effect. First, it provides excellent metal protection. This is because the huge planar conjugated system composed of a triazine ring and three benzene rings is adsorbed onto the metal surface through π-π stacking and van der Waals forces. At the same time, the three terminal substituents act as electron-donating groups to form coordination bonds with the empty d orbitals of the metal. This dual mechanism of "surface adsorption" providing a physical barrier and "point coordination" providing chemical anchoring forms a strong and stable protective layer. Second, it provides efficient photoresist stripping. The nucleophilic groups carried at the ends of the branches of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative can synergistically attack the ester bonds and amide bonds of the photoresist polymer chain at three sites under alkaline conditions. Compared with the random and single-point attack of small molecule amines, the multi-directional simultaneous disintegration of the photoresist crosslinking network can fragment the macromolecules, effectively improving the stripping efficiency of highly crosslinked (carbonized) photoresists after ion implantation and plasma etching. Third, excellent thermochemical stability. The rigid conjugated structure makes its chemical bonds more stable, and they are not easy to break or decompose at high temperatures. This allows the molecules to be stably anchored to the metal surface, making them less prone to desorption and providing continuous protection throughout the degumming process.
[0031] In this invention, the alkane-ketone organic solvent comprises one or more of N-methylpyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, N-hydroxyethylpyrrolidone, N-dodecylpyrrolidone, N-cyclohexylpyrrolidone, 1-butyl-2-pyrrolidone, 1-benzyl-2-pyrrolidone, 1-cyclohexyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, and N-isopropylpyrrolidone.
[0032] In this invention, the sulfoxide organic solvent comprises one or more of dimethyl sulfoxide, diethyl sulfoxide, dipropyl sulfoxide, methyl phenyl sulfoxide, benzyl methyl sulfoxide, cyclohexyl sulfoxide, and sulfolane.
[0033] In this invention, the alkanolamine organic solvent comprises one or more of monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, and diethylene glycolamine.
[0034] The present invention also provides a method for preparing the above-mentioned photoresist stripping solution, comprising the following steps: weighing the above-mentioned raw materials respectively, then mixing alkyl ketone organic solvent, sulfoxide organic solvent and alkanolamine organic solvent and adding functional additives until completely dissolved to obtain photoresist stripping solution.
[0035] The present invention also provides an application of the above-described photoresist stripping solution in stripping photoresist from semiconductor chips.
[0036] In this invention, the step of stripping the photoresist from the semiconductor chip is as follows: the semiconductor chip is immersed in a photoresist stripping solution and subjected to ultrasonic treatment to obtain the semiconductor chip after photoresist removal.
[0037] In this invention, the temperature of the photoresist stripping solution is 70~90℃, specifically 70℃, 75℃, 80℃, 85℃, or 90℃; the ultrasonic treatment time is 10~60min, specifically 10min, 20min, 30min, 40min, 50min, or 60min.
[0038] This invention achieves a breakthrough in the field of semiconductor cleaning by utilizing the selective removal of photoresist and the stabilizing film formation on the surface of metal electrodes through functional additives.
[0039] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0040] Example 1
[0041] The raw material composition of the photoresist stripping solution is: 74 parts of N-methylpyrrolidone, 10 parts of dimethyl sulfoxide, 15 parts of triethanolamine, 0.5 parts of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, and 0.5 parts of methyl 4-isopentenyloxycinnamate.
[0042] N-methylpyrrolidone, dimethyl sulfoxide and triethanolamine were mixed evenly, and then 2,4,6-tris(4-aminophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0043] Example 2
[0044] The raw material composition of the photoresist stripping solution is: 71.5 parts of N-methylpyrrolidone, 15 parts of sulfolane, 12 parts of monoethanolamine, 1 part of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, and 0.5 parts of methyl 4-isopentenyloxycinnamate.
[0045] N-methylpyrrolidone, sulfolane, and monoethanolamine were mixed evenly, and then 2,4,6-tris(4-aminophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0046] Example 3
[0047] The raw material composition of the photoresist stripping solution is: 62 parts of N-cyclohexylpyrrolidone, 15 parts of dimethyl sulfoxide, 20 parts of isopropanolamine, 2 parts of 2,4,6-tris(4-methylaminophenyl)-1,3,5-triazine, and 1 part of methyl 4-isopentenyloxycinnamate.
[0048] N-cyclohexylpyrrolidone, dimethyl sulfoxide and isopropanolamine were mixed evenly, and then 2,4,6-tris(4-methylaminophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0049] Example 4
[0050] The raw material composition of the photoresist stripping solution is: 62 parts of N-ethylpyrrolidone, 20 parts of diethyl sulfoxide, 16 parts of diisopropanolamine, 1 part of 2,4,6-tris(4-ethylaminophenyl)-1,3,5-triazine, and 1 part of methyl 4-isopentenyloxycinnamate.
[0051] N-ethylpyrrolidone, diethyl sulfoxide and diisopropanolamine were mixed evenly, and then 2,4,6-tris(4-ethylaminophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0052] Example 5
[0053] The raw material composition of the photoresist stripping solution is: 56.5 parts of N-cyclohexylpyrrolidone, 30 parts of sulfolane, 12 parts of diethylene glycolamine, 0.5 parts of 2,4,6-tris(4-mercaptophenyl)-1,3,5-triazine, and 1 part of methyl 4-isopentenyloxycinnamate.
[0054] N-cyclohexylpyrrolidone, sulfolane, and diethylene glycolamine were mixed evenly, and then 2,4,6-tris(4-mercaptophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added. The mixture was stirred until completely dissolved to obtain the photoresist stripping solution.
[0055] Example 6
[0056] The raw material composition of the photoresist stripping solution is: 66 parts of N-methylpyrrolidone, 18 parts of dipropyl sulfoxide, 15 parts of monoethanolamine, 0.5 parts of 2,4,6-tris(4-hydroxyethylaminophenyl)-1,3,5-triazine, and 0.5 parts of methyl 4-isopentenyloxycinnamate.
[0057] N-methylpyrrolidone, dipropyl sulfoxide and monoethanolamine were mixed evenly, and then 2,4,6-tris(4-hydroxyethylaminophenyl)-1,3,5-triazine and methyl 4-isopentenyloxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0058] Comparative Example 1
[0059] The raw material composition of the photoresist stripping solution is: 74 parts of N-methylpyrrolidone, 10 parts of dimethyl sulfoxide, 15 parts of triethanolamine, 0.5 parts of 3-amino-1,2,4-triazole, and 0.5 parts of methyl 4-isopentenyloxycinnamate.
[0060] N-methylpyrrolidone, dimethyl sulfoxide and triethanolamine were mixed evenly, and then 3-amino-1,2,4-triazole and methyl 4-isopentenyloxycinnamate were added. The mixture was stirred until completely dissolved to obtain the photoresist stripping solution.
[0061] Comparative Example 2
[0062] The raw material composition of the photoresist stripping solution is: 71.5 parts of N-methylpyrrolidone, 15 parts of sulfolane, 12 parts of monoethanolamine, 1 part of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, and 0.5 parts of methyl 4-hydroxycinnamate.
[0063] N-methylpyrrolidone, sulfolane, and monoethanolamine were mixed evenly, and then 2,4,6-tris(4-aminophenyl)-1,3,5-triazine and methyl 4-hydroxycinnamate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0064] Comparative Example 3
[0065] The raw material composition of the photoresist stripping solution is: 66.5 parts of N-cyclohexylpyrrolidone, 12 parts of dimethyl sulfoxide, 20 parts of isopropanolamine, 1 part of 2,4,6-tris(4-methylaminophenyl)-1,3,5-triazine, and 0.5 parts of methyl 4-vinylbenzoate.
[0066] N-cyclohexylpyrrolidone, dimethyl sulfoxide and isopropanolamine were mixed evenly, and then 2,4,6-tris(4-methylaminophenyl)-1,3,5-triazine and methyl 4-vinylbenzoate were added and stirred until completely dissolved to obtain the photoresist stripping solution.
[0067] Comparative Example 4
[0068] The raw material composition of the photoresist stripping solution is: 73 parts of N-ethylpyrrolidone, 10 parts of diethyl sulfoxide, 16 parts of diisopropanolamine, 0.5 parts of melamine, and 0.5 parts of methyl 4-isopentenyloxycinnamate.
[0069] N-ethylpyrrolidone, diethyl sulfoxide and diisopropanolamine are mixed evenly, then melamine and methyl 4-isopentenyloxycinnamate are added and stirred until completely dissolved to obtain photoresist stripping solution.
[0070] Application examples
[0071] Photoresist stripping was performed on semiconductor chips using the photoresist stripping solutions of Examples 1-6 and Comparative Examples 1-4.
[0072] The photoresist stripping solution was heated to 90°C in a water bath. After the temperature stabilized, different metal electrode chips were simultaneously immersed in different photoresist stripping solutions. The chips were then sonicated at 90°C for 60 minutes. After sonication, the chips were removed, rinsed twice with deionized water, and then dried with nitrogen to complete the chip cleaning process.
[0073] The corrosion rate of the aforementioned photoresist stripping solution on the chip was determined using the following method: a four-probe method was employed to test the degree of corrosion of the metal by different photoresist stripping solutions, and the corrosion rate was calculated. Specifically, uniformly sized metal electrode sheets were continuously sonicated in a 90℃ photoresist stripping solution for 60 minutes, rinsed twice with deionized water, and dried with nitrogen. Based on the four-probe method, the thickness of the metal sheet before and after sonication in the photoresist stripping solution was measured, and the average value was used to calculate the corrosion rate (nm / min), thus examining the corrosion effect of different photoresist stripping solutions on the metal. The test results are shown in Table 1. Table 1. Results of adhesive removal and corrosion rate tests.
[0074] As can be seen from Table 3, the photoresist stripping solutions of Examples 1-6 of the present invention have excellent metal protection and cleaning capabilities. Compared with Example 1, Comparative Example 1 used 3-amino-1,2,4-triazole to replace 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, resulting in an increased Al corrosion rate and photoresist residue after cleaning; Comparative Example 2 used methyl 4-hydroxycinnamate to replace methyl 4-isopentenyloxycinnamate, resulting in an increased Al corrosion rate. Comparative Example 3 used a combination of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine and methyl 4-vinylbenzoate as a functional additive. Due to the lack of the synergistic corrosion inhibition effect of methyl 4-isopentenyloxycinnamate, the Al corrosion rate increased. Comparative Example 4 used a combination of melamine and methyl 4-isopentenyloxycinnamate as a functional additive. Due to the lack of the synergistic corrosion inhibition effect of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, the Al corrosion rate increased and the photoresist was not cleaned properly.
[0075] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A photoresist stripping solution, characterized by comprising: The photoresist stripping solution comprises the following components in parts by weight: 20-75 parts of alkyl ketone organic solvent, 5-30 parts of sulfoxide organic solvent, 5-20 parts of alkanolamine organic solvent, and 0.1-5 parts of functional additives. The functional additives are 2,4,6-tris(4-phenyl)-1,3,5-triazine derivatives and methyl 4-isopentenyloxycinnamate.
2. The photoresist stripping solution according to claim 1, wherein The structural formula of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative is shown in (I): （Ⅰ） Wherein, R is selected from amino, methylamino, ethylamino, isopropylamino, hydroxyethylamino, amide, mercapto, sulfonic acid, or carboxyl.
3. The photoresist stripping solution according to claim 1 or 2, characterized by The mass ratio of the 2,4,6-tris(4-phenyl)-1,3,5-triazine derivative and methyl 4-isopentenyloxycinnamate is 0.5~3:0.5~2.
4. The photoresist stripping solution according to claim 3, wherein The alkane-ketone organic solvents include one or more of N-methylpyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, N-hydroxyethylpyrrolidone, N-dodecylpyrrolidone, N-cyclohexylpyrrolidone, 1-butyl-2-pyrrolidone, 1-benzyl-2-pyrrolidone, 1-cyclohexyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, and N-isopropylpyrrolidone.
5. The photoresist stripping solution according to claim 2 or 4, wherein The sulfoxide organic solvents include one or more of dimethyl sulfoxide, diethyl sulfoxide, dipropyl sulfoxide, methyl phenyl sulfoxide, benzyl methyl sulfoxide, cyclohexyl sulfoxide, and sulfolane.
6. The photoresist stripping solution of claim 5, wherein The alkanolamine organic solvents include one or more of monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, and diethylene glycolamine.
7. The production method of the photoresist stripping solution according to any one of claims 1 to 6, characterized by, The process includes the following steps: weigh the above raw materials separately, then mix the alkyl ketone organic solvent, sulfoxide organic solvent and alkanolamine organic solvent and add the functional additive until completely dissolved to obtain the photoresist stripping solution.
8. The application of the photoresist stripping solution according to any one of claims 1 to 6 in stripping photoresist from semiconductor chips.
9. The use of the photoresist stripping solution according to claim 8 for stripping a photoresist from a semiconductor chip, characterized in that The steps for removing the photoresist from the semiconductor chip are as follows: the semiconductor chip is immersed in a photoresist stripping solution and subjected to ultrasonic treatment to obtain the semiconductor chip after photoresist removal.
10. The use of the photoresist stripping solution according to claim 9 for stripping a photoresist from a semiconductor chip, characterized in that The temperature of the photoresist stripping solution is 70~90℃; the ultrasonic treatment time is 10~60min.