Role of electron and ion irradiation in a reliable lift-off process with electron beam evaporation and a bilayer PMMA resist system

Abstract

This paper addresses issues related to cracking and blisters in deposited films encountered in a lift-off process with electron beam evaporation and a bilayer PMMA resist system. The impact of charged particles, i.e., electrons and ions, is investigated using an electron beam evaporation chamber equipped with ring-magnets and a plate electrode placed in front of the sample. By replacing the plate electrode with a hollow metallic cylinder, the modified evaporation setup utilizing passive components allows complete elimination of resist shrinkage and bubble formation yielding near perfect deposition results for a large variety of different materials.