JP-7855648-B2 - Photoresist stripping solution and method of use thereof

Inventors

• 袁敬堯
• 趙成▲禮▼
• ▲頼▼修平

Assignees

• 南亞塑膠工業股▲分▼有限公司

Dates

Publication Date

20260508

Application Date

20240809

Priority Date

20240618

Claims (6)

1. A photoresist stripping solution comprising a first stripping solution and a second stripping solution, which are packaged separately and do not contain an organic base, The first stripping solution is An inorganic base containing potassium hydroxide and sodium hydroxide, Benzotriazole 1% to 15% by weight, Surfactant in an amount of 2% to 10% by weight, Contains water, The second stripping solution is Alcohol ether-based solvent in a concentration of 30% to 80% by weight, Benzotriazole 1% to 15% by weight, Contains water, A photoresist stripping solution characterized in that the concentration of the inorganic base in the first stripping solution is 30 g/L to 45 g/L.
2. The photoresist stripping solution according to claim 1, wherein the weight ratio of potassium hydroxide to sodium hydroxide is 2.5 to 6.
3. The photoresist stripping solution according to claim 1, wherein the surfactant is selected from the group consisting of sodium dodecyl sulfate, octadecyltrimethylammonium hydroxide, alkyldimethylphenylammonium hydroxide, alkyl sulfate salts, phosphate salts, sulfosuccinates, glutamates, lauryl betaine, cocamidopropyl betaine, and potassium polyoxyethylene lauryl ether phosphate.
4. The photoresist stripping solution according to claim 1, wherein the alcohol ether-based solvent is selected from the group consisting of diethylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol propyl ether, dipropylene glycol propyl ether, propylene glycol n-butyl ether, diethylene glycol dibutyl ether, tripropylene glycol methyl ether, ethylene glycol butyl ether, ethylene glycol propyl ether, diethylene glycol hexyl ether, diethylene glycol diethyl ether, and diethylene glycol dimethyl ether.
5. A method for using a photoresist stripping solution according to any one of claims 1 to 4, wherein the method for using the photoresist stripping solution is: Applying the first stripping solution to the circuit board, Applying the second stripping solution to the circuit board, A third stripping solution is prepared by mixing the first stripping solution and the second stripping solution in a weight ratio of 1:1 to 2:3 (first stripping solution: second stripping solution) and further adding 1 to 2.5 times the amount of water. This includes applying the third stripping solution to the circuit board, The first stripping solution contains no organic base, but comprises the inorganic base, 1% to 15% by weight of the benzotriazole , 2% to 10% by weight of the surfactant, and water, and the concentration of the inorganic base in the first stripping solution is 30 g/L to 45 g/L. A method for using a photoresist stripping solution, characterized in that the second stripping solution does not contain an organic base and contains 30% to 80% by weight of the alcohol ether solvent, 1% to 15% by weight of the benzotriazole , and water.
6. A method for using a photoresist stripping solution according to claim 5, wherein the first stripping solution, the second stripping solution, and the third stripping solution are applied to the circuit board by spraying.

Description

This invention relates to a photoresist stripping solution and a method of using the same, and more particularly to a photoresist stripping solution that does not contain organic amines and a method of using the same. The manufacturing process for circuit boards includes steps such as forming a copper surface, applying and developing a photoresist to the copper surface and covering a portion of the copper surface with a dry film, etching the exposed copper surface, and stripping the dry film. In the process of removing dry film, a stripping solution is typically used to remove the photoresist dry film covering the fine pitch. Currently, existing stripping solutions, primarily composed of sodium hydroxide, have the advantages of low cost and fast stripping speed, but they generate a relatively large amount of scrap after stripping. This results in a defect where the film cannot be cleanly removed from the fine pitch, leading to circuit boards that fail quality control. Therefore, other types of film release solutions containing inorganic and organic bases are also commercially available. Organic bases are typically amine compounds such as ethanolamine and ethylenediamine. Combining inorganic and organic bases yields superior release effects. However, the presence of organic amines generates a pungent odor in the release solution, so there is room for improvement. Therefore, eliminating the use of organic amines while maintaining a certain degree of exfoliation effect through compositional improvements is one of the important challenges for this company. This is a flowchart showing a method for using the photoresist stripping solution according to the present invention.This is a schematic diagram illustrating the stripping process performed on a circuit board. To further understand the features and technical content of this invention, please refer to the following detailed description and drawings relating to the invention. However, the provided drawings are for reference and illustrative purposes only and do not limit the scope of the claims of this invention. The following describes a "photoresist stripping solution and method of use thereof" by specific embodiments, and those skilled in the art will be able to understand the advantages and effects of the present invention based on the disclosure herein. The present invention can be implemented or applied by other different specific embodiments, and various modifications and changes can be made to each detail herein, based on different perspectives and applications, without departing from the concept of the present invention. It should also be noted that the accompanying drawings of the present invention are for simple schematic purposes only and are not drawn to actual size. The technical content of the present invention will be described in more detail below based on the following embodiments, but the scope of protection of the present invention is not limited by the disclosed content. Furthermore, the term "or" as used herein may include any one or more combinations of the items listed relevantly, depending on the actual situation. In this invention, by adjusting the formulation of the stripping solution and improving the method of using the stripping solution, a good stripping effect can still be achieved even after removing organic bases (amine compounds) from the photoresist stripping solution. Therefore, the photoresist stripping solution of this invention can be used for fine pitches of 3 mil or more, replacing existing stripping solutions with pungent odors. The photoresist stripping solution according to the present invention is a two-component type photoresist stripping solution comprising a first stripping solution and a second stripping solution, each packaged separately. The first and second stripping solutions may be used independently, or they may be used after being mixed. This combination exhibits excellent stripping effects on all currently commercially available photoresists. For example, applicable photoresists include ADH photoresists (photoresists containing acrylic monomers), t-BOC photoresists (photoresists containing tert-butoxycarbonyl groups), and acetal photoresists (photoresists containing PHS copolymers), but the present invention is not limited to these. The above types are merely examples and do not limit the types of photoresists that can be applied. In a photoresist stripping solution, the first stripping solution is for stripping the dry film (formed by the photoresist). The second stripping solution does not actually have a stripping effect, but it can expand the dry film. The expanded dry film reacts more easily with the first stripping solution and can be removed from the circuit board. In other words, the second stripping solution can assist the first stripping solution in stripping the dry film. [First stripping solution] The first stripping solution is an aqueous solution and does not contain an organic base (amine