KINETIC FEATURES OF THE ETCHING OF SEVERAL POLYIMIDE MATERIALS IN OXYGEN PLASMAS

The etching of a number of polyimides and polyamide acids in oxygen pl asmas is studied for the purpose of clarifying the influence of their structure on the etching behavior. The temperature dependences of the etching rates, as well as of the release of gaseous products and the a bsorption of oxygen, are measured. The rate of etching of the polyimid es is less than that of the corresponding polyamide acids by a factor of 2. It is shown that other than a dependence on the structure of the se polymers, there are characteristic temperature regions for etching in which the activation energies are identical in all cases. It is sug gested that the limiting stage is the association of oxygen through di fferent forms of active centers that are formed in the plasma.