Influence of post-deposition annealing in oxygen ambient on metal–organic decomposed CeO2 film spin coated on 4H-SiC

Abstract

Post-deposition annealing (PDA) was performed in oxygen ambient at different temperatures (600, 800, 1,000 and 1,150 °C) onto metal–organic decomposition (MOD) prepared CeO2 film spin coated on n-type 4H-SiC substrate. Effects of PDA onto the physical and electrical characteristics of MOD-derived CeO2 were investigated. Four orientations [(111), (200), (220), and (311)] of CeO2 peaks were revealed by X-ray diffraction analysis in all of the samples with a preferred orientation in (200) direction. However, α-Ce2O3 and cerium silicate (Ce2Si2O7) interfacial layers emerged at 1,150 °C. As annealing temperature increased, grain size of films was increased but microstrains were decreased. Electrical results indicated that negative effective oxide charge and slow trap density were decreased as temperature increased. The lowest interface trap density was perceived by sample annealed at 1,000 °C. However, the highest electric field was obtained by sample annealed at 1,150 °C. Reasons that contributed to this observation were discussed.