Method of forming a resist pattern by radiation exposure of positive-working resist coating comprising a dye and a trihydroxybenzophenone compound and subsequent aqueous alkaline development

Claim 1

A method of forming a resist pattern on a substrate comprising: coating said substrate with a layer of a positive-working photoresist composition; exposing said layer patternwise to actinic radiation; and removing the exposed portions of said layer with an aqueous alkaline developer for the exposed resist composition to uncover the areas of the substrate beneath the exposed portions; said positive-working photoresist composition comprising a solvent and solid ingredients dissolved therein; said solids, whose proportions are based by weight on the total solids in said composition, comprise: (a) from about 63 to about 68 percent of a novolak resin; (b) from about 15 to about 22 percent of a naphthoquinone diazide sensitizer prepared by mono-, di- or tri-esterifying a low molecular weight phenol compound with 1,2-naphthoquinone-2-diazide-5-chloride, said phenol compound having the formula ##STR5## wherein: R is a single bond or one of the groups CO, S, 0, SO 2 or CR 6 R 7 ; R 1 , R 2 , R 3 , R 4 and R 5 are each independently H, X (where X is a halogen atom), OH, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxy group having 1 to 4 carbon atoms; and R 6 and R 7 are each independently H or a lower alkyl group having 1 to 4 carbon atoms; or wherein: two of the radicals R 3 , R 4 and R 5 or the two radicals R 1 and R 2 independently jointly form an aromatic ring, whereby at least one of the radicals R 1 , R 2 , R 3 , R 4 or R 5 is OH; (c) from about 0.1 to about 3 percent of a dye a which absorbs light at a maximum wavelength of from about 330 to about 460 nm; and (d) an effective proportion of an additive compound to increase the photospeed and rate of development of said composition, said additive compound being a trihydroxybenzophenone compound and said proportion ranging from about 10 to about 20 percent.

Claim 2

A method of forming a resist pattern on a substrate comprising: coating said substrate with a layer of a positive-working photoresist composition; exposing said layer patternwise to actinic radiation; and removing the exposed portions of said layer with an aqueous alkaline developer for the exposed resist composition to uncover the areas of the substrate beneath the exposed portions; said positive-working photoresist composition comprising a solvent and solid ingredients dissolved therein; said solids, whose proportions are based by weight on the total solids in said composition, comprise: (a) from about 63 to about 68 percent of a novolak resin; (b) from about 15 to about 22 percent of a naphthoquinone diazide sensitizer prepared by mono-, di- or tri-esterifying a low molecular weight phenol compound with 1,2-naphthoquinone-2-diazide-5-chloride, said phenol compound having the formula ##STR5## wherein: R is a single bond or one of the groups CO, S, 0, SO 2 or CR 6 R 7 ; R 1 , R 2 , R 3 , R 4 and R 5 are each independently H, X (where X is a halogen atom), OH, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxy group having 1 to 4 carbon atoms; and R 6 and R 7 are each independently H or a lower alkyl group having 1 to 4 carbon atoms; or wherein: two of the radicals R 3 , R 4 and R 5 or the two radicals R 1 and R 2 independently jointly form an aromatic ring, whereby at least one of the radicals R 1 , R 2 , R 3 , R 4 or R 5 is OH; (c) from about 0.1 to about 3 percent of a dye a which absorbs light at a maximum wavelength of from about 330 to about 460 nm; and (d) an effective proportion of an additive compound to increase the photospeed and rate of development of said composition, said additive compound being a trihydroxybenzophenone compound and said proportion ranging from about 10 to about 20 percent.