Improvement of SiO2/4H-SiC(0001) Interface Properties by H2 and Ar Mixture Gas Treatment Prior to SiO2 Deposition


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We investigated the impact of high-temperature H2/Ar mixture gas treatment of 4H-SiC(0001) surfaces before SiO2 deposition on the electrical properties of SiO2/SiC interfaces. Physical characterizations revealed that the SiC surface treated by the H2/Ar mixture gas exhibited a (√3×√3)R30° structure composed of Si-O bonds, indicating that a well-ordered and stable silicate adlayer was formed by the treatment to passivate SiC(0001) surface. Electrical defects at the CVD-grown SiO2/SiC interface was significantly reduced by the treatment. Consequently, a peak electron mobility in SiC-MOSFETs with the deposited gate oxides was enhanced to 24.9 cm2/Vs.



Edited by:

Robert Stahlbush, Philip Neudeck, Anup Bhalla, Robert P. Devaty, Michael Dudley and Aivars Lelis




H. Tsuji et al., "Improvement of SiO2/4H-SiC(0001) Interface Properties by H2 and Ar Mixture Gas Treatment Prior to SiO2 Deposition", Materials Science Forum, Vol. 924, pp. 461-464, 2018

Online since:

June 2018




* - Corresponding Author

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