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Title: Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC

Abstract

The conduction mechanism of the leakage current of a thermally grown oxide on 4H silicon carbide (4H-SiC) was investigated. The dominant carriers of the leakage current were found to be electrons by the carrier-separation current-voltage method. The current-voltage and capacitance-voltage characteristics, which were measured over a wide temperature range, revealed that the leakage current in SiO{sub 2}/4H-SiC on the Si-face can be explained as the sum of the Fowler-Nordheim (FN) tunneling and Poole-Frenkel (PF) emission leakage currents. A rigorous FN analysis provided the true barrier height for the SiO{sub 2}/4H-SiC interface. On the basis of Arrhenius plots of the PF current separated from the total leakage current, the existence of carbon-related defects and/or oxygen vacancy defects was suggested in thermally grown SiO{sub 2} films on the Si-face of 4H-SiC.

Authors:
;  [1];  [2]; ; ; ; ; ; ; ;  [1]
  1. Advanced Power Electronics Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, 305-8568 Ibaraki (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
22412836
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 2; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CAPACITANCE; CARBON; CHARGE CARRIERS; ELECTRIC CONDUCTIVITY; ELECTRIC POTENTIAL; ELECTRONS; FILMS; INTERFACES; LEAKAGE CURRENT; SILICON CARBIDES; SILICON OXIDES; TEMPERATURE DEPENDENCE; TUNNEL EFFECT; VACANCIES

Citation Formats

Sometani, Mitsuru, Takei, Manabu, Fuji Electric Co. Ltd., 1 Fuji-machi, Hino, 191-8502 Tokyo, Okamoto, Dai, Harada, Shinsuke, Ishimori, Hitoshi, Takasu, Shinji, Hatakeyama, Tetsuo, Yonezawa, Yoshiyuki, Fukuda, Kenji, and Okumura, Hajime. Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC. United States: N. p., 2015. Web. doi:10.1063/1.4905916.
Sometani, Mitsuru, Takei, Manabu, Fuji Electric Co. Ltd., 1 Fuji-machi, Hino, 191-8502 Tokyo, Okamoto, Dai, Harada, Shinsuke, Ishimori, Hitoshi, Takasu, Shinji, Hatakeyama, Tetsuo, Yonezawa, Yoshiyuki, Fukuda, Kenji, & Okumura, Hajime. Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC. United States. doi:10.1063/1.4905916.
Sometani, Mitsuru, Takei, Manabu, Fuji Electric Co. Ltd., 1 Fuji-machi, Hino, 191-8502 Tokyo, Okamoto, Dai, Harada, Shinsuke, Ishimori, Hitoshi, Takasu, Shinji, Hatakeyama, Tetsuo, Yonezawa, Yoshiyuki, Fukuda, Kenji, and Okumura, Hajime. Wed . "Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC". United States. doi:10.1063/1.4905916.
@article{osti_22412836,
title = {Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC},
author = {Sometani, Mitsuru and Takei, Manabu and Fuji Electric Co. Ltd., 1 Fuji-machi, Hino, 191-8502 Tokyo and Okamoto, Dai and Harada, Shinsuke and Ishimori, Hitoshi and Takasu, Shinji and Hatakeyama, Tetsuo and Yonezawa, Yoshiyuki and Fukuda, Kenji and Okumura, Hajime},
abstractNote = {The conduction mechanism of the leakage current of a thermally grown oxide on 4H silicon carbide (4H-SiC) was investigated. The dominant carriers of the leakage current were found to be electrons by the carrier-separation current-voltage method. The current-voltage and capacitance-voltage characteristics, which were measured over a wide temperature range, revealed that the leakage current in SiO{sub 2}/4H-SiC on the Si-face can be explained as the sum of the Fowler-Nordheim (FN) tunneling and Poole-Frenkel (PF) emission leakage currents. A rigorous FN analysis provided the true barrier height for the SiO{sub 2}/4H-SiC interface. On the basis of Arrhenius plots of the PF current separated from the total leakage current, the existence of carbon-related defects and/or oxygen vacancy defects was suggested in thermally grown SiO{sub 2} films on the Si-face of 4H-SiC.},
doi = {10.1063/1.4905916},
journal = {Journal of Applied Physics},
number = 2,
volume = 117,
place = {United States},
year = {Wed Jan 14 00:00:00 EST 2015},
month = {Wed Jan 14 00:00:00 EST 2015}
}
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