PROGRESS IN ACETAL BASED DEEP UV RESIST

Abstract

Acetal based deep UV resists, AZ^® DX series, are high performance, positive tone deep UV resists consisting of poly(3-methyl, 4- hydroxystyrene-co-4-hydroxystyrene) matrix resin, poly(N, O-acetal) dissolution inhibitor, bis(arylsulfonyl) diazomethane photoacid generator and a photobase to stabilize the latent acid image. The resist can lineate structures between 0.35 and 0.25μm using KrF laser (248nm) source. In the present paper, the background for the selection of current components and the function of the photobase is presented. Finally, the lithographic properties of the acetal based resist, AZ^® DX 46 is presented, demonstrating the usefulness of the resist for 64 and 256Mbit DRAM manufacturing.