Consistency between experimental data for ambipolar diffusion length and for photoconductivity when incorporated into the “standard'' defect model for <i>a</i>-Si:H

Reasonable consistency between experimental data for the ambipolar diffusion length and experimental data for the photoconductivity is demonstrated for steady-state measurements performed on <i>a</i>-Si:H layers. This consistency is obtained based on the “standard'' defect model for <i>a</i>-Si:H. In this model the dangling bonds are taken into account, considering their amphoteric behavior and treating then as recombination centers, whereas the band tails are taken into account as simple two-valued defects acting as traps. Consistency is obtained based on (1) a particular form of the recombination function such as is considered appropriate for the dangling bonds, as well as, additionally, (2) the local charge neutrality condition. The experimental data analyzed are power laws of the ambipolar diffusion length and of the photoconductivity (versus light intensity); they are obtained for a series of slightly <i>p</i> and <i>n</i>-doped samples including the undoped case.