| abstract |
A negative photoresist composition which provides a good resolution in a pattern formation process wherein a lower layer film is provided on a substrate, a photoresist film of a negative photoresist composition is provided on the lower layer film, the photoresist film is selectively exposed, and thereafter, the lower layer film and the photoresist film are developed at the same time. The resist composition contains (A) an alkali soluble resin, (B) an acid releasing agent which releases an acid by exposure to radiation, and (C) a crosslinking agent, wherein the acid releasing agent (B) contains an onium salt containing a cation with no hydrophilic group. |