Patent ID: 8507175
Filing Date: 2013-08-13
Classification: G03F

Abstract:
1. A process for forming a pattern comprising the steps of applying a resist composition onto a substrate to form a resist film, baking, exposure to radiation at a dose, post-exposure baking, and developing with an alkaline developer, said resist composition comprising a polymer comprising recurring units having an acid labile group and recurring units (a1), (a2), (a3) or (a4) in the general formula (1) as a photobase generator capable of generating an amino group and substantially insoluble in the alkaline developer, a photoacid generator capable of generating an acid, a quencher having an amino group for neutralizing the acid released from the photoacid generator for inactivation, and an organic solvent, the sum of a total molar amount of amino groups in the quencher and a total molar amount of amino groups released from the photobase generator is greater than a total molar amount of the acid released from the photoacid generator, whereby a pattern of the resist film is formed including an unexposed region at a low exposure dose and an over-exposed region at an excess exposure dose which are not dissolved in the developer, and an exposed region at an intermediate exposure dose which is dissolved in the developer, wherein R 1 , R 7 , R 12 , and R 17 each are hydrogen or methyl, R R R R R a1, a2, a3, a4 are numbers in the range: 0≦a1<1.0, 0≦a2<1.0, 0≦a3<1.0, 0≦a4<1.0, and 0<a1+a2+a3+a4<1.0.