Thermally Grown Native Oxide Thin Films on SiC

Integration of high quality functional thin layer of oxides on semiconductor, in particular wide-bandgap silicon carbide (SiC), is of extreme importance in order to generate metal-oxide-semiconductor based devices for high power, high temperature and/or high radiation applications in the future. This chapter reviews the current understanding of surface modification of SiC by thermally grown native oxide thin films. In the first section, importance of SiC as a semiconductor substrate and the need of gate oxide are presented. This is followed by a discussion on growth mechanisms, types and origin of oxide trap charges and interfacial and near interfacial traps in SiC/SiO₂ system. Besides, the current technological process for the improvements of SiO₂/SiC system and the promising techniques for achieving device-quality interfaces that is required for commercial applications are also reviewed. Finally, factors influencing a high quality oxide on SiC, namely process ambient, oxidation/nitridation parameters and semiconductor substrate are also systematically compared, discussed and reviewed. Based on the knowledge and understanding of these topics, further improvements on the fabrication technology of gate oxide can be obtained.