Effect of film thickness on a-Si:H properties grown with hydrogen diluted silane

a-Si:H films prepared by plasma-enhanced CVD with 10% SiH4 in hydrogen have been studied concerning the effect of film thickness on the hydrogen concentration, interconnected void network and mechanical stress. The hydrogen concentration was determined by nuclear reaction analysis. The interconnected void network was studied by the method of ion exchange in glass substrate. The films were prepared at a substrate temperature in the range of 150 - 270°C. The results show that at the substrate temperature of 150°C the film structure develops as the void network decreases with the film thickness. At the substrate temperature of 270°C the film starts to grow with a dense structure and its structural improvement is manifested by the increase of the intrinsic compressive stress with the film thickness. The hydrogen concentration does not depend on the film thickness at any substrate temperature.