Photoresist is a pattern transfer medium, which uses light reaction after different solubility to transfer mask pattern to the substrate. At present, it is widely used in the processing of fine graphic circuit in photoelectric information industry and is a key material in the field of electronic manufacturing. Semiconductor lithography glue, for example, in the lithography process, photoresist is evenly coated on the substrate, after exposure (change the photoresist solubility), development (using the soluble part of the solution dissolving photoresist modified) and the etching process, such as the graphics on the mask version transferred to the substrate, formation and mask version completely corresponding geometric shapes. Photolithography process accounts for about 35% of the entire chip manufacturing cost and 40-60% of the entire chip process time, which is the most core process in semiconductor manufacturing.

Photoresist is mainly composed of photosensitive agent (photoinitiator), polymerization agent (photosensitive resin), solvent and auxiliaries. Photoinitiator is the most critical component of photoresist, which plays a decisive role in the sensitivity and resolution of photoresist. Photosensitive resin is used to polymerize different materials in photoresist. It is the skeleton of photoresist and determines the basic properties of photoresist, including hardness, flexibility and adhesion. The solvent is the largest component of the photoresist and is intended to keep the resist in liquid state, but the solvent itself has little effect on the chemical properties of the photoresist. Auxiliaries are usually proprietary compounds, developed by individual manufacturers and used to modify specific chemical properties of photoresist.

Photoresist can be classified in the following three ways:

1) According to the chemical reaction principle and development principle, it can be divided into positive photoresist and negative photoresist;

2) According to the different chemical structure of raw materials, it can be divided into photopolymerization, photopolymerization and photopolymerization;

3) According to different downstream application fields, it can be divided into semiconductor photoresist, panel photoresist and PCB photoresist. The downstream field of photoresist mainly includes semiconductor, panel, PCB and LED industries.


Photoresist has been the core material of semiconductors since its invention in 1959, and has since been modified to make PCB boards and, in the 1990s, flat-panel displays. Final applications include consumer electronics, home appliances, automotive communications, etc.

The development direction of photoresist industry is basically determined by the downstream demand, and the semiconductor field is the sub-field with the highest technical threshold. Photoresist products are one of the materials with the highest technical barriers in electronic chemicals. They not only have the characteristics of high purity requirement and complex process, but also need to be matched and adjusted by corresponding lithography machines. In general, a semiconductor chip in the manufacturing process needs to carry out 10-50 photolithography process, because the substrate is different, resolution requirements are different, etching methods are different, different photolithography process specific requirements for photoresist are not the same, even if similar photolithography process, different manufacturers will have different requirements. There are many types of photoresist for different applications, and these differences are mainly realized by adjusting the formulation of photoresist. Therefore, it is the core technology for photoresist manufacturers to adjust the formula of photoresist to meet the needs of differentiated applications.