Effect of atomic bonding configuration on optical properties of a-Si1−xCx:H thin film

a-Si1−xCx:H thin film with adjustable optical band gap and photoluminescence (PL) property has been strongly demanded for various optoelectronic applications. The control of atomic bonding within the film has been considered as a promising approach to address such challenge. In this study, a range of a-Si1−xCx:H thin films prepared using plasma enhanced chemical vapor deposition (PECVD) were annealed at different temperature. It was found that the content of Si–Hn group and C–Hn group decreased with the increased temperature from 200°C to 600°C, and consequently more Si–C bonds and sp3 hybridized C clusters were formed. Such atomic bonding configuration variation was found to induce enlarged optical band gap. In addition, the PL wavelength was effectively adjusted, and its efficiency was significantly enhanced. The underlying relationship between the atomic bonding characteristics and the optical properties of a-Si1−xCx:H was extensively discussed. This study has therefore been an important step forward to its further advanced applications.