Optimization of 4H-SiC MOS Properties with Cesium Implantation
The effect of incorporation of cesium with implantation on the electrical characteristics of SiO2/4H-SiC interface has been evaluated using MOS capacitors. With a cesium dosage of 1012 and 3x1012 cm-2 on deposited oxide re-oxidized in steam, effective oxide charge densities of - 1.4x1012 and -7.5x1011 cm-2 respectively were extracted and a cesium implant activation percentage of 33% was estimated from flatband voltage shift. Also, corresponding interfacial state densities of 2.5x1013 and 1.8x1013 cm-2-eV-1 near the conduction band edge were extracted from High-Low frequency C-V technique, showing a decreasing Dit with increasing Cs dosage.
Akira Suzuki, Hajime Okumura, Tsunenobu Kimoto, Takashi Fuyuki, Kenji Fukuda and Shin-ichi Nishizawa
Y. Wang et al., "Optimization of 4H-SiC MOS Properties with Cesium Implantation", Materials Science Forum, Vols. 600-603, pp. 751-754, 2009