Abstract: A layer of P-type hydrogenated amorphous silicon having a wide band gap and relatively low conductivity is formed by subjecting a substance to a gaseous mixture of a silicon hydride and an acceptor material in a glow discharge while heating the substrate to a temperature of no greater than 120.degree. C. The deposited acceptor-doped hydrogenated amorphous silicon layer is then heated at a temperature of between 130.degree. C. and 300.degree. C. to increase the conductivity of the layer.