FABRICATION OF a-Si: H THIN FILMS BY A DOUBLE TUBED COAXIAL-LINE TYPE MICROWAVE PLASMA CVD SYSTEM.

This study was concerned with the fabrication of a-Si:H thin films by a double tubed coaxial-line type microwave plasma CVD system. The cw microwave of 60 w and pulsed microwave, of which the average power is 60 w and the duty ratio is 1/5, are used. The deposition rate is 0. 1 to 7 A/s dependent on the substrate position from the discharge tube end. The optical energy band gap is 1. 7 to 1. 9 ev. The boundary layer between the plasma region excited by the microwave power and the after-glow region created spatially have been estimated by using the experimental results of the dependence of the deposition rate and the optical energy band gap on the substrate position. In the spatially after-glow region, satisfactory thin films are fabricated without a plasma bombardment.