| abstract |
The present invention provides a novel onium salt having the following formula (1), and a resist composition comprising the onium salt as a quencher. When the resist composition is processed by photolithography using high energy rays, an improved resist pattern in LWR and CDU is formed. In the above formula, R 1 , R 2 and R 3 are each independently a linear, branched or cyclic monovalent hydrocarbon group of C 1 -C 20 which may contain hetero atoms other than fluorine atoms, and Z + is sulfonium , Iodonium or ammonium cation. |