Silicon-containing polymer and its use as a masking resin in a lithography process

Claim 1

A process for masking certain zones of a substrate, wherein it comprises the following successive stages: (a) depositing on said substrate a first resin layer having a thickness such that it constitutes a levelling layer for the substrate, (b) depositing on said first resin layer, a second photosensitive film layer which comprises (1) at least one silicon-containing polymer in accordance with the formula: ##STR24## in which R 1 represents H or an alkyl radical of one to four carbon atoms, R 2 , R 3 , and R 4 , being the same or different, represent an alkyl radical of one to four carbon atoms, Z represents --O--, (CH 2 ) n --O-- with n being an integer between 1 and 4, or ##STR25## with R 5 , R 6 and R 7 , being the same or different, representing an alkyl radical of one to four carbon atoms, and m being a number between 25 and 2000, and (2) at least one salt which is converted into a Brunsted acid upon irradiation at a wavelength in the given wavelength range, (c) irradiating the zones of the second layer corresponding to the substrate zones which are not to be masked, by means of radiation with a wavelength corresponding to the photosensitivity range of the photosensitive film, and (d) eliminating the second photosensitive film layer and the first resin layer at the points corresponding to the zones of the second layer which have been irradiated.