Anomalously High Channel Mobility in SiC-MOSFETs with Al2O3/SiOx/SiC Gate Structure
4H-SiC MOSFETs with Al2O3/SiC and Al2O3/SiOx/SiC gate structures have been fabricated and characterized. Al2O3 was deposited by metal-organic chemical vapor deposition (MOCVD) and the SiOx layer was formed by dry-O2 oxidation. Insertion of 1.2 nm-thickness-SiOx layer drastically improves the channel mobility of Al2O3/SiC-MOSFET and anomalously high field effect mobility (μFE) of 284 cm2/Vs was obtained. The μFE of Al2O3/SiOx/SiC-MOSFET with various SiOx thickness was investigated, and it was found that insertion of a thin SiOx layer (< 2 nm) followed by the low temperature deposition of Al2O3 results in Al2O3/SiOx/SiC-MOSFET with such a high channel mobility.
Akira Suzuki, Hajime Okumura, Tsunenobu Kimoto, Takashi Fuyuki, Kenji Fukuda and Shin-ichi Nishizawa
S. Hino et al., "Anomalously High Channel Mobility in SiC-MOSFETs with Al2O3/SiOx/SiC Gate Structure ", Materials Science Forum, Vols. 600-603, pp. 683-686, 2009