Anomalous Optical and Structural Properties of B-Doped a-Si:H

Abstract

The optical absorption edge spectra, the bonded H content and H evolution measurements have been carried out on B-doped a-Si:H as functions of the dopant gas ratio of B₂H₆/SiH₄. The number of H atoms bonded to Si network decreases as the doping ratio increases, while non-bonded H's are involved only in the heavily B-doped specimen. It has been demonstrated that the film texture changes drastically in a high doping region, resulting in anomalous change in the optical absorption spectra over a whole photon-energy range.