A Review of Total Dry Resist Process

Abstract

A progress of total dry resist process for e-beam lithography using plasma polymerization for resist casting and plasma etching for development, mostly by our group, is reviewed. i) Use of flow type reactor, ii) copolymerization of e-beam sensitive monomer with etch-resistive monomer, iii) sensitization by high-z atom, and iv) use of hydrogen plasma for development gave rise to a great extent of e-beam sensitivity which finally reached to 5μC/cm². A modeling study of dry development have shown a linear dependence of logalithmic film thickness change to the logalithmic scission fraction per monomer unit, λ. A 0.15 of λ is found to be necessary which figure will explain observed decrese of e-beam sensitivity by dry development from that by wet development. Several way to improve dry devlopment process and also dry devlopable X-ray resign is discussed on the basis of knowleges so far obtained.