In this payer, the preparation of amorphous silicon carbide with very wide optical band gap and high conductivity were reported. The films were fabricated under the "silane-plasma starving" and H-2 dilution condition in conventional capacitively coupled reactors. The silane-plasma starving condition and H-2 dilution play important roles in decreasing H content, modulating the material toward the ordered structure and enhancing the doping ratio. This is an easy way to prepare wide optical band gap and highly conductive p-type window layers for a-Si:H-based solar cells. (C) 2001 Elsevier Science B.V. All rights reserved.