Share Email Print

Proceedings Paper

Comparison of wet and dry gate oxides for SiC MOSFETs
Author(s): Philip G. Tanner; Sima Dimitrijev; H. Barry Harrison
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

SiC MOSFETs are currently being developed for use in RF, microwave, and switch mode power supply applications, but the process conditions required for high quality and reliable oxides are not yet optimized. This paper present result of a fundamental study comparing wet and dry oxidation of SiC. Equivalent 4H-SiC substrates were cleaned and prepared under identical conditions before oxides were grown in either wet or dry ambients, followed by an inert gas anneal. Capacitance-voltage curves show increased net effective charge and density of interface states in the upper half of the SiC bandgap due to wet oxidation of n-SiC compared to dry oxidation. In contrast, wet oxidation of p- SiC reduces the density of donor-like states in the lower half of the SiC bandgap compared to dry oxidation. Current- voltage curves reveal more low-field leakage as a result of wet oxidation. When oxides on n-type substrates are stressed at room temperature using a dielectric field strength of 9MV/cm, increased hole trapping is seen at the oxide- semiconductor interface of wet oxide devices compared to dry oxide devices. Stressing at a higher temperature and lower field results in similar changes in net effective charge fort he two oxides, although the wet oxide shows considerably more increase in low-field leakage current.

Paper Details

Date Published: 1 October 1999
PDF: 7 pages
Proc. SPIE 3892, Device and Process Technologies for MEMS and Microelectronics, (1 October 1999); doi: 10.1117/12.364498
Show Author Affiliations
Philip G. Tanner, Griffith Univ. (Australia)
Sima Dimitrijev, Griffith Univ. (Australia)
H. Barry Harrison, Griffith Univ. (Australia)

Published in SPIE Proceedings Vol. 3892:
Device and Process Technologies for MEMS and Microelectronics
Kevin H. Chau; Sima Dimitrijev, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?