Deep etching of biocompatible silicone rubber

Fluorine-based reactive ion etching of commercial biocompatible silicone rubber based on poly(methylhydrogensiloxane-co-dimethylsiloxane) has been studied. The basic aim was to investigate the etch rates and the etch profiles obtained under various plasma conditions. The effect of process pressure on the polysiloxane morphology was also examined. Polysiloxane layers supported on the standard silicon wafers were etched using SF"6+O"2 or CF"4+O"2 plasmas. The etch rate of the polymer in a SF"6+O"2 plasma (over 1@mm/min) was found to be higher than that in a CF"4+O"2. The advantageous effect of a higher pressure on the etch rate was revealed. The etch rate enhancement with pressure was more pronounced in an SF"6+O"2 plasma than in an CF"4+O"2 plasma. Significant changes in elastomer morphology were found after the plasma treatment and their dependence on plasma conditions was described.