title: Controlling the defects and transition layer in SiO2films grown on 4H-SiC via direct plasma-assisted oxidation.
abstract: The structural stability and electrical performance of SiO2grown on SiC via direct plasma-assisted oxidation were investigated. To investigate the changes in the electronic structure and electrical characteristics caused by the interfacial reaction between the SiO2film (thickness ~5 nm) and SiC, X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), density functional theory (DFT) calculations, and electrical measurements were performed. The SiO2films grown via direct plasma-assisted oxidation at room temperature for 300s exhibited significantly decreased concentrations of silicon oxycarbides (SiOxCy) in the transition layer compared to that of conventionally grown (i.e., thermally grown) SiO2films. Moreover, the plasma-assisted SiO2films exhibited enhanced electrical characteristics, such as reduced frequency dispersion, hysteresis, and interface trap density (Dit≈ 1011cm-2· eV-1). In particular, stress induced leakage current (SILC) characteristics showed that the generation of defect states can be dramatically suppressed in metal oxide semiconductor (MOS) structures with plasma-assisted oxide layer due to the formation of stable Si-O bonds and the reduced concentrations of SiOxCyspecies defect states in the transition layer. That is, energetically stable interfacial states of high quality SiO2on SiC can be obtained by the controlling the formation of SiOxCythrough the highly reactive direct plasma-assisted oxidation process.
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749 Korea.
authors.forename: Dae-Kyoung
authors.initials: DK
authors.lastname: Kim
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749 Korea.
authors.forename: Kwang-Sik
authors.initials: KS
authors.lastname: Jeong
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749 Korea.
authors.forename: Yu-Seon
authors.initials: YS
authors.lastname: Kang
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749 Korea.
authors.forename: Hang-Kyu
authors.initials: HK
authors.lastname: Kang
authors.affiliation: Department of Physics, Yonsei University, Wonju 220-710, Korea.
authors.forename: Sang W
authors.initials: SW
authors.lastname: Cho
authors.affiliation: Department of Biomedical Engineering, Seonam University, Namwon 55724, Korea.
authors.forename: Sang-Ok
authors.initials: SO
authors.lastname: Kim
authors.affiliation: Process Development Team, Semiconductor R&D Center, SAMSUNG, Hwaseong-si 18448, Korea.
authors.forename: Dongchan
authors.initials: D
authors.lastname: Suh
authors.affiliation: Process Development Team, Semiconductor R&D Center, SAMSUNG, Hwaseong-si 18448, Korea.
authors.forename: Sunjung
authors.initials: S
authors.lastname: Kim
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749 Korea.
authors.forename: Mann-Ho
authors.initials: MH
authors.lastname: Cho