Electrical characterization of radio frequency sputtered hydrogenated amorphous silicon carbide films

Abstract

The electrical results of rf sputtered hydrogenated amorphous silicon carbide (a-Si1−xCx:H) films prepared under different sputtering conditions are presented. It was found that hopping and Poole–Frenkel effects are the conduction mechanisms for low and high applied fields, respectively. From the capacitance versus voltage measurements, the fixed charge density (Qf) and the interface trapped charge density (Dit) were found to be in the range of 5.5–6.81×1010 cm−2 and 5–13×1011 eV−1 cm−2, respectively. Dit decreases with either an increase in the total sputtering pressure, the partial hydrogen pressure, or the substrate temperature, but increases with an increase in the rf sputtering power. The decrease in Dit was found to be closely related to the increase in the number of silicon–hydrogen bonds.