Deposition of silicon-germanium alloys under plasma modulation conditions

Plasma deposition of a-Si,Ge:H,F films from SiF4-GeH4-H2 mixture, has been investigated by applying a square wave modulation to the r.f. field. The effects of plasma modulation on the thickness and compositional uniformity and on the increase of Ge and H incorporation in the film are reported. A twophases model for the conduction mechanism is preliminarily discussed.