High-resolution negative photoresist and preparation method thereof

Abstract

The invention relates to the field of optical materials, in particular to a high-resolution negative photoresist. According to the acrylic acid modified epoxy resin which is an alkali-soluble negativephotoresist, acrylic acid is used as a component for introducing double bonds, and a carboxyl group is consumed every time one double bond is introduced, so that the solubility of film-forming resinin a developing solution is difficult to ensure, and higher LER and lower resolution are easily caused; and the film-forming resin contains more epoxy functional groups, so that the adhesive force between the film-forming resin and a silicon wafer is greatly reduced, and the resolution of a photoetching pattern is very unfavorable. For the problems above, the invention provides the high-resolution negative photoresist; rich hydroxyl functional groups and rigid structures are introduced into a side chain of photosensitive resin, and through compounding of two reactive diluents, the photosensitive resin obtains proper crosslinking density, so that the adhesive force of the photosensitive resin on a silicon wafer is effectively improved, the resolution of a photoetching image is greatly improved, and the photoetching image has small LER.

Description

technical field [0001] The invention relates to the field of optical materials, in particular to a high-resolution negative photoresist. Background technique [0002] Photoresist refers to the photosensitive mixed liquid whose solubility in the developer is changed by the irradiation or radiation of the ultraviolet light exposure light source. It is a key material in the integrated circuit industry chain and is mainly used in the fine patterns of microelectronics and semiconductor discrete devices. processing. [0003] Photoresist is composed of film-forming resin, photosensitizer, additives and solvents, among which film-forming resin is a key component, which can undergo photochemical reactions and determine the sensitivity, resolution and solubility of photoresist. [0004] The alkali-soluble negative type photoresist of commercialization is mainly the epoxy resin of acrylic acid modification, but the brittleness of this type of resin is big, causes line edge roughness e...

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