The Scope and Mechanism of New Positive Tone Gas‐Phase‐Functionalized Plasma‐Developed Resists

Abstract

A new type of plasma‐developed positive acting photo and electron‐beam resist is described. It is based upon the difference in functionalization occurring when exposed resists such as Waycoat IC‐43 and Selectilux N‐60 are treated with gaseous inorganic halides. Unexposed areas etch slowly during reactive ion etching. In these areas, azide‐inorganic halide complexes are readily converted to a masking metal oxide layer. In the exposed areas, inorganic amino halides are converted to volatile organic and inorganic compounds. Thicknesses in excess of 5000Å result for 8s contact photoexposures at 366 nm followed by treatment with and reactive ion etching. In addition, 0.6 μm resolution is attained. Electron beam exposures indicate resolution capabilities of less than 0.3 μm, with sensitivity on the order of 10–20 μC/cm2 at 20 keV. A mechanism consistent with UV, infrared, Rutherford backscattering, ESCA, and kinetic data is presented.