Optical Degradation of a-Si:H films with Different Morphology

Abstract

The optical degradation (Staebler-Wronski (SW) effect) of a-Si:H films prepared by plasma CVD has been studied in connection with the morphological inhomogeneity of the films. The relative degradation rate of cubic photoconductivity α widely varied with deposition substrate temperature T _s and had its maximum at T _s=200∼250°C. In the films of both the lower and higher T _s, α decreased due to the increase of stable dangling bonds in the former and the decrease of weak bonds in the latter. The SW effect was hardly observed in µc-Si:H deposited from highly diluted silane with hydrogen.