Patent ID: 6440646
Filing Date: 2002-08-27
Classification: G03F

Abstract:
A method for forming a pattern comprising the steps of:forming a resist layer on one surface of a substrate wherein said resist layer is constructed of a positive resist composition for use in a lift-off technique comprising in admixture, (A) a 1,2-naphthoquinonediazidosulfonyl-introduced novolak resin containing at least one recurring unit of the following general formula (1): wherein m is an integer of 0 to 3, and having a weight average molecular weight calculated as polystyrene of 2,000 to 20,000, 2.5 to 27 mol % of the hydrogen atom of a hydroxyl group in the novolak resin being replaced by a 1,2-naphthoquinonediazidosulfonyl group, and (B) a low molecular aromatic compound having phenolic hydroxyl groups and 2 to 20 benzene rings, the ratio of the number of phenolic hydroxyl groups to the number of benzene rings being from 0.5 to 2.5, said low molecular aromatic compound being represented by the following general formula (2) or (3): wherein m is an integer of 0 to 2, n is an integer of 0 to 2, with the proviso that m is equal to 1 or 2 when n is equal to 0, R1 to R6 are independently selected from the class consisting of a hydrogen atom, a methyl group, a group of the following formula (4), and a group of the following formula (5), A is hydrogen, methyl or a group of the following formula (4) when n is 0 and m is 1; one A is methylene or a group of the following formula (6) and the other A is hydrogen, methyl or a group of the following formula (4) when n is 0 and m is 2; A is methylene or a group of the following formula (6) when n is 1; A is methine or a group of the following formula (7) when n is 2 and m is 1; and one A is methylene or a group of the following formula (6) and the other A is methine or a group of the following formula (7) when n is 2 and m is 2, h is a sufficient number to give a weight average molecular weight of 200 to 2,500, wherein p, q, r, s, and t each are an integer of 0 to 3, processing the resist layer to form a resist pattern, metallizing the substrate surface including the resist pattern, and stripping off the resist pattern to leave a pattern of metallization on the substrate, wherein said resist layer constituting said resist pattern is formed with an undercut.