Microwave Plasma CVD System to Fabricate α-Si Thin Films out of Plasma

Abstract

This study has been concerned with the development of a system to fabricate thin films by a microwave plasma chemical vapour deposition method while keeping the substrate out of the discharge plasma. Si thin films are fabricated in a deposition region using an improved coaxial line type microwave CW discharge tube without a silicon deposition on the discharge tube wall. A very uniform Si thin film has been fabricated over a circle with a 10 cm diameter and the deposition rates are 50 to 400 Å/min. The structure of the fabricated films is amorphous and the optical band gap is 1.8 to 2.0 eV.