Patterning process

A patterning process to form a metal film pattern on a coated film having an exposure pattern formed thereon, comprising the steps of:

• (1) coating a substrate to be processed with a first resist material containing a thermosetting compound having a hydroxy group and/or a carboxy group each protected by an acid-labile group, an acid generator, and a sensitizer, followed by baking treatment to form a first resist film being insoluble to an organic solvent;
• (2) irradiating the first resist film with a high energy beam from a light source of an extreme ultraviolet ray with a wavelength of 3 to 15 nm or an electron beam to perform pattern exposure to deprotect the hydroxy group and/or the carboxy group in a pattern exposed portion of the first resist film;
• (3) coating the first resist film subjected to the pattern exposure with a second resist material containing a component (A) of at least one element selected from the group consisting of a metal compound, a hydrolysate of the metal compound, a condensate of the metal compound, and a hydrolysis condensate of the metal compound, followed by baking treatment to form a second resist film and to form a crosslinked portion in which the component (A) and the deprotected hydroxy group and/or the deprotected carboxy group are crosslinked on the pattern exposed portion;
• and
• (4) developing the second resist film with a developer to give a metal film pattern composed of the crosslinked portion.