Staebler-wronski effect in a-Si:H films with different morphology

Abstract Optical degradation (Staebler-Wronski effect) of a-Si:H and annealing of optically induced defects has been studied in connection with the morphological inhomogeneity of the films. The relative degradation rate α widely varied with deposition substrate temperature T s and has 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. Thermal and optical annealing of degradation were also studied. It was found from AC conductivity measurements that band conductivity was strongly affected by the degradation but that hopping conductivity was not. A degradation-resistant film was obtained by lamp annealing and subsequent exposure to a hydrogen plasma.