Optical and structural properties of polycrystalline 3C-SiC films

In this letter, polycrystalline 3C-SiC (111) films were deposited by plasma enhanced chemical vapor deposition system at a temperature of 670 degrees C using a gas mixture of SiH4/CH4/H-2/(CF4). The optical properties of deposited films with different feed gases and different structures were investigated. In these studies, a broad photoluminescence band was observed for films with lower crystallinity and the radiative transitions between the conduction and valance band tails were suggested as the origin of the observed peak. The band gap of these polycrystalline SiC films was estimated at around 2.10 eV. (c) 2006 American Institute of Physics.