Characterization of amorphous SiC:H thin films grown by RF plasma enhanced CVD on annealing temperature

In this work, we investigated the dependence of optical and electrical properties of hydrogenated amorphous silicon carbide (a-SiC:H) films on annealing temperature (T_a) and radio frequency (RF) power. The substrates temperature (T_s) was 250°C, the RF power was varied from 30 W to 400 W, and the range of T_a was from 400°C to 600°C. The a-SiC:H films were deposited by using PECVD (plasma enhanced chemical vapor deposition) system on Corning glass and p-type Si (100) wafer with a SiH₄+CH₄ gas mixture. The experimental results have shown that optical band gap energy (E_g) of the a-SiC:H thin films changed little with the annealing temperature while E_g increased with the RF power. The Raman spectrum of the thin films annealed at high temperatures showed that graphitization of carbon clusters and microcrystalline silicon occurs. The current-voltage characteristics have shown good electrical properties in relation to the annealed films.