Method for forming positive patterned resist layer on tantalum substrate utilizing quinone diazide composition with aromatic hydroxy additive

A method for forming a patterned resist layer on a substrate, of which at least the surface layer is made from tantalum, which comprises the steps of:

• (A) coating the substrate surface with a positive-working photosensitive resin composition comprising, as a uniform blend,
• (a) an alkali-soluble novolac resin;
• (b) a quinone diazide group-containing organic compound;
• and
• (c) an aromatic compound having two benzene rings in a molecule selected from the group consisting of (c-1) the compounds represented by the general formula ##STR6## in which R.sup.1 to R.sup.10 are each, independently from the others, a hydrogen atom, alkyl group having 1 to 4 carbon atoms, alkenyl group, halogen atom, hydroxy group, alkoxy group or carboxyl group including at least five hydroxy groups and X is a divalent atom or group of the formula --CO--O--, --CO--, --S--, --SO--, --SO.sub.2 --, --O-- or --CR.sub.2 --, each R being an alkyl group, (c-2) a compound expressed by the structural formula ##STR7## and (c-3) a compound expressed by the structural formula ##STR8## to form a resist layer;
• (B) exposing the resist layer pattern-wise to actinic rays to form a latent image in the resist layer;
• and
• (C) developing the latent image in the resist layer by treating said layer with an aqueous solution to remove the imagewise exposed areas.