193nm photoresist film-forming resin, preparation method thereof and positive photoresist composition

Abstract

The invention discloses 193nm photoresist film-forming resin, a preparation method thereof and a positive photoresist composition, and belongs to the technical field of semiconductor microelectronic chemistry. The 193nm positive photoresist contains film-forming resin and a photoacid generator, and the film-forming resin contains the following components in percentage by mole: 5-40% of a composition unit containing a cholic acid derivative; 10%-50% of a constituent unit containing a polar group; 10%-40% of a unit containing an acid-sensitive group; the cholic acid derivative unit is at least one compound conforming to a chemical general formula (I); the constituent unit of the polar group refers to at least one compound conforming to a chemical general formula (II); the acid-sensitive group unit is at least one compound conforming to a chemical general formula (III). The cholic acid-containing derivative is introduced as a film-forming resin unit, so that the adhesiveness, the dissolution inhibition effect and the graphic contrast of the film-forming resin can be improved, and the line edge roughness is reduced.

Description

technical field [0001] The invention relates to a photoresist used in ultra-large-scale integrated circuit chips, in particular to a photoresist using 193nm deep ultraviolet single beam light as an exposure light source, and belongs to the technical field of semiconductor microelectronic chemistry. Background technique [0002] Photoresist, also known as photoresist, refers to an etching-resistant film material whose solubility changes under irradiation or radiation of ultraviolet light, electron beam, ion beam, X-ray, etc. In recent years, with the trend of miniaturization, light weight and portability of electronic and electrical products, the integration of VLSI chips has become higher and higher, and the wavelength of the lithography exposure light source of semiconductor chips has been continuously shortened, from 365nm (i-line) Developed to 248nm (KrF), 193nm (ArF), 13nm (EUV). In order to improve the sensitivity of the photoresist, the current mainstream KrF, ArF, an...

AI Technical Summary

Problems solved by technology

Usually, in order to meet the anti-etching standard, the macromolecule anti-etch group of ester ring structure is usually contained in the resin structure, such as adamantane, norbornanol, etc. When used, it is easy to cause resin solubility problems, resulting in small residues in the exposed area and irregular jagged edges

And the acid produced by the photoacid generator after exposure will diffuse to the non-exposed area, resulting in increased line edge roughness

The existing technology adopts the addition of organic base and dissolution inhibitor to suppress the diffusion of acid, but in practical application, it is found that these two technical solutions do not completely solve the problem, because the organic base will not only neutralize the acid in the non-exposed area, It will also neutralize the acid in the exposed area, resulting in a decrease in the solubility of the resin in the exposed area; the same dissolution inhibitor is usually a macromolecular compound with some polar groups, and there are factors of self-agglomeration and agglomeration, which cannot completely prevent the acid in the exposed area Solubilization Effect of Diffusion on Resin in Non-exposed Areas

There are also some scientific research literature and invention patents that the problem of acid diffusion can be solved by adding photoacid generator monomers to film-forming resins. In fact, the effect is very limited, because although photoacid generators cannot diffuse, the photoacid generators after exposure The resulting acid is still free to diffuse

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