High Quality Amorphous Silicon Prepared by Catalytic Chemical Vapor Deposition (CTL-CVD) Method

Abstract

AbstractA new method of producing high quality hydrogenated amorphous silicon (a-Si:H) and its compound films is presented. An SiH4 and H2 gas mixture is decomposed without using any plasmas or photochemical excitation, but using only thermal and catalytic reactions between deposition gas and a heated tungsten catalyzer. Photoconductivity of a-Si:H films produced by, this method reaches 10−3 (Ωcm)−1 and photosensitivity exceeds 105 for illumination of AM-1 light of 100 mW/cm2, highly efficient boron- or phosphorus-doping into the films is achieved, and also the optical band gap of the films is easily controlled without apparent degradation of the properties by adding GeH4 gas to the deposition gas.