Resist design for resolution limit of KrF imaging towards 130 nm lithography

A strategy of resist design for the resolution limit of KrF imaging is investigated, and then the possibility of 130 nm lithography using KrF imaging is discussed. An extremely thin resist in a thickness of less than 150 nm was developed for KrF imaging at the resolution limit. The resist could overcome crucial problems of nanoedge roughness as well as degraded resist profiles without sacrificing resolution capability even when reducing the resist thickness to extreme limits. Moreover, a resist thickness of 80 nm could narrowly perform 130 nm lithography using an unconventional KrF imaging system featuring a numerical aperture of 0.6 and a partial coherency of 0.75 with 2/3 annular aperture, without using any phase shift mask technologies. (C) 1998 American Vacuum Society. [S0734-211X(98)16506-X].