Polymer light-sensitive layers for photochemical etching of Al films

The dry photochemical etching of aluminium films has been studied using the etchers (Opal Blue dye and acids), which are produced by illumination of the light-sensitive polymer layers cast on top of these films. These layers, consisting of different polymer binders, ferrocene [(C5H5)(2)Fe], diphenylamine (DPA) and tetrabromomethane (CBr4) have a high light-sensitivity owing to autocatalytic post-exposure accumulation of etchers. In this process the catalytic system Fe(III)/Fe(II) is formed directly from components dissolved in the polymer binder as a result of photochemical reaction. The Al film having a thickness of 0.65 mu m is dissolved into the polymer layers completely after exposure H-0 = 4 mJ cm(-2) to 365 nm.