Abstract: A novel radiation-sensitive resin composition having high sensitivity and high O.sub.2 -RIE resistance is otained by blending 0.5 g of poly(di-t-butoxysiloxane), 50 mg of triphenylsulfonium trifluoromethanesulfonate as acid-producing agent, and 4 ml of 2-methoxyethyl acetate as solvent.

Abstract: A photoresist composition is disclosed. The photoresist composition comprises a base resin, a photosensitizer, and a solvent. The base resin comprises polyhydroxystyrene represented by the following structural formula (I): ##STR1## (wherein k is a positive integer). The photosensitizer comprises a polyhalogen compound(s). The photoresist composition of the present invention has dry etching resistance characteristics comparable to those of conventional positive novolak photoresist compositions and can form a resist pattern with a high resolution and vertical sidewall profiles. This makes microprocessing possible.

Abstract: A pattern-forming material is made by halogenoacetylation of the hydroxyl group of the copolymer of hydroxystyrene, and methyl methacrylate or ethyl methacrylate copolymer. The pattern-forming material in this invention is based on a resin copolymer of hydroxystyrene which has excellent dry etching resistance properties and methyl methacrylate or hydroxy ethyl methacrylate which is transparent to deep UV radiation over a relatively wide spectral range, combined with halogenoacetyl groups as photoreactive groups. Further, as the pattern-forming materials of this invention are soluble in the various liquids described below, a resist solution can easily be prepared, and a film of the material can easily be formed by the spin coating process.

Abstract: A negative resist material consists of poly (silsesquioxane) of weight average molecular weight 2000 or more represented by the general formula (1):(CH.sub.2 .dbd.CHCH.sub.2 SiO.sub.3/2).sub.m (ClCH.sub.2 SiO.sub.3/2).sub.n (1)where m and n denote the molar percentages of each component of the polymer, and m+n=100. A method of producing such a resist material and a method of forming a bi-layer resist pattern using the resist material are also disclosed.