A study of deep traps at the SiO2/6H-SiC interface relying upon the nonequilibrium field effect

• Published in: Semiconductors (Woodbury, N.Y.) Vol. 35; no. 4; pp. 468 - 473
• Main Authors: Ivanov, P. A., Samsonova, T. P., Panteleev, V. N., Polyakov, D. Yu
• Format: Journal Article
• Language: English
• Published: New York Springer Nature B.V 01-04-2001
• Subjects: Absorption cross sections; Beta decay; Depletion; Electron capture; Energy distribution; High temperature; MOSFETs; Oxidation; Silicon carbide; Silicon dioxide
• ISSN: 1063-7826; 1090-6479
• DOI: 10.1134/1.1365197

The nonequilibrium field effect associated with deep surface states at the SiO2/6H-SiC interface has been observed and studied in a 6H-SiC MOSFET of depletion-accumulation type. An analysis of the relaxation of channel conductance at elevated temperatures upon filling of the surface traps with nonequilibrium carriers has shown that the energy distribution of the surface traps has the form of a narrow Gaussian peak in the upper half of the 6H-SiC band gap, with a peak energy EC−Etm = 1.19eV, peak width ΔEt≈85 meV, and electron capture cross section σn≈10−14 cm2. These surface states are believed to have the fundamental nature of “oxidation defects” similar to Pb centers in the SiO2-Si system (of dangling silicon bonds).