Subharmonics and rf-plasma sheaths

Abstract

Period doubling and concomitant subharmonic generation have been reported in rf-excited plasmas. We show that this phenomenon is caused by the nonlinear interaction of the plasma-sheath capacitance with the external rf power circuits. As a result, changes in the external circuits can be used to control period doubling. Sheath capacitance can be derived from electrical measurements of period doubling.