Re-emission Coefficients of Si and SiO2 Films Deposited through rf and dc Sputtering

Abstract

Re-emission coefficients for SiO2 films and for Si films deposited through rf sputtering have been measured as a function of pressure and input power. Values for SiO2 were 0.86−0.30 and for Si 0.45−0.07. High re-emission coefficients correlated with negative potentials on the deposit surface, which, in turn, caused resputtering of the deposit by positive ions drawn from the glow discharge. The existence of additional mechanisms for re-emission was established for rf-sputtered silicon deposited at zero substrate bias. The re-emission coefficient of dc-sputtered silicon was found to have values comparable to those of rf sputtering.