4H-SiC MOSFETs Using Thermal Oxidized Ta2Si Films as High-k Gate Dielectric
Oxidized Ta2Si layers have been used as high-k dielectric layer for 4H-SiC MOSFETs. The gate insulator was grown by dry oxidation of 40nm deposited Ta2Si during 1h at 1050oC. The dielectric constant obtained from 4H-SiC MIS capacitors is ~20 with an insulator thickness of 150nm. These devices exhibit adequate subthreshold, saturation and drive characteristics. For the MOSFETs fabricated on a p-implanted and annealed region, a peak mobility up to 45cm2/Vs has been extracted. The specific on-resistance of this device is 29mW·cm2 at room temperature with VDS=0.2V and VGS=14V.
Dr. Roberta Nipoti, Antonella Poggi and Andrea Scorzoni
A. Pérez-Tomás et al., "4H-SiC MOSFETs Using Thermal Oxidized Ta2Si Films as High-k Gate Dielectric", Materials Science Forum, Vols. 483-485, pp. 713-716, 2005