Influence of intense illumination on dispersive hydrogen diffusion in a-Si:H

Abstract With elastic-recoil detection analysis (ERDA) we have measured the variation of the dispersion parameter α of hydrogen diffusion in undoped a-Si:H as a function of illumination intensities I (I=8 and 15 W/cm 2 ) at an annealing temperature T a =350°C. The α value in the illuminated case was then compared to the α dark value. We found that α increases with I. To our knowledge, this is the first observation of this effect. The hydrogen diffusion mechanisms under intense illumination for both film types are discussed in the framework of existing models.