Fabrication of 4H-SiC p-Channel MOSFET with High Channel Mobility
We have fabricated inversion-type p-channel MOSFETs on 4H-SiC substrates. In this paper, influences of gate oxidation process on the properties of p-channel MOSFETs were investigated. The gate oxide was formed under these three conditions: (i) dry oxidation, (ii) dry oxidation following wet re-oxidation, and (iii) wet oxidation. The C-V measurements of p-type 4H-SiC MOS capacitors revealed that wet oxidation process reduced the interface states near the valence band. The p-channel MOSFET with low interface states near the valence band indicated low threshold voltage (Vth), high field effect channel mobility (μFE) and low subthreshold swing (S). We obtained 4H-SiC p-channel MOSFET with high μFE of 15.6cm2/Vs by using wet oxidation as gate oxidation process.
Robert P. Devaty, David J. Larkin and Stephen E. Saddow
M. Okamoto et al., "Fabrication of 4H-SiC p-Channel MOSFET with High Channel Mobility", Materials Science Forum, Vols. 527-529, pp. 1301-1304, 2006