[3] [3] Yan F, Xin X B, et al. 4H-SiC UV photo detectors with large area and very high specific detectivity [J]. IEEE J. Quantum Electron., 2004, 40: 1315-1320.

[4] [4] Chen X P, Zhu H L, Cai J F, et al. High-performance 4H-SiC-based ultraviolet p-i-n photodetector [J]. J. Appl. Phys., 2007, 102: 024505.

[5] [5] Afanas’ev V V, Stesmans A, Cheong K Y, et al. Mechanisms responsible for improvement of 4H-SiC/SiO2 interface properties by nitridation [J]. Appl. Phys. Lett., 2003, 82(427): 558.

[6] [6] Soares G V, Radtke C, Baumvol I J R, et al. Morphological and compositional changes in the SiO2/SiC interface region induced by oxide thermal growth [J]. Appl. Phys. Lett., 2006, 88(4): 041901.

[8] [8] Hazra S, Chakraborty S, Lai P T. Density profiles and electrical properties of thermally-grown oxide nanofilms on p-type 6H-SiC(0001) [J]. Appl. Phys. Lett., 2004, 85: 5580.

[9] [9] Morrison D J, Pidduck A J, Moore V, et al. Surface preparation for Schottky metal-4H-SiC contacts formed on plasma-etched SiC [J]. Semicond. Sci. Technol., 2000, 15(12): 1107-1114.

[11] [11] Moulder J F, Stickle W F, et al. Handbook of X-ray Photoelectron Spectroscopy [Z]. Physical Electronics Inc., 1995.

[12] [12] Viard J, Beche E, Perarnau D, et al. XPS and FTIR study of silicon oxynitride thin films [J]. Journal of the European Ceramic Society, 1997, 17: 2025-2028.

[13] [13] Virojanadara C, Johansson L I. Photoemission study of Si-rich 4H-SiC surfaces and initial SiO2/SiC interface formation [J]. Phys. Rev. B, 2005, 71: 195335.

[14] [14] Hijikata Y, Yaguchi H, Yoshikawa M, et al. Composition analysis of SiO2/SiC interfaces by electron spectroscopic measurements using slope-shaped oxide films [J]. Appl. Surf. Sci., 2001, 184: 161-166.

[15] [15] Ekoue A, Renault O, Billon T, et al. Study of the wet re-oxidation annealing of SiO2/4H-SiC(0001) interface properties by AR-XPS measurements [J]. Mater. Sci. Forum, 2003, 433-436: 555-558.