Stability of undoped hydrogenated amorphous silicon multilayer film grown with alternating substrate temperature

Undoped hydrogenated amorphous silicon films have been grown in multilayers with alternating substrate temperature between optimal and nonoptimal temperature for device-quality films. Compared to the single layer films grown at optimal substrate temperature, the multilayer films show improved stability in the light-induced state. Under intense light illumination of 3 W/cm(2), the steady-state defect density of the layered film reaches a saturation of 2x10(16) cm(-3), while the cm single layer film saturates at 6x10(16) cm(-3). It is found that in the completely degraded state, the photoconductivity in the multilayer film is also improved by a factor of 3 compared to the singlelayer film. (C) 1996 American Institute of Physics.