Affiliation:
1. U.S. Army Research Laboratory
2. Berkeley Research Associates
3. University of Maryland
Abstract
We have observed instability in the threshold voltage, VT, of SiC metal-oxide
semiconductor field-effect transistors (MOSFETs) due to gate-bias stressing. This effect has
routinely been observed by us in all 4H and 6H SiC MOSFETs from three different
manufacturers—even at room temperature. A positive-bias stress, applying an electric field of
about 1 to 2 MV/cm across the gate oxide, for 3 minutes followed by a negative-bias stress for
another 3 minutes typically results in a shift of the ID-VGS current-voltage characteristic in the range
of 0.25 to 0.5 V and is repeatable. We speculate that this effect is due to the presence of a large
number of near-interfacial oxide traps that presumably lie in the oxide transition region that extends
several nm into the oxide from the SiC interface, caused by the presence of C and strained SiO2.
This instability is consistent with charge tunneling in and out of these near-interfacial oxide traps,
which in irradiated Si MOSFETs has been attributed to border traps. Also consistent with charge
tunneling is the observed linear increase in the magnitude of the SiC VT instability with log (time).
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
Reference7 articles.
1. For example: G.Y. Chung, C.C. Tin, J.R. Williams, K. McDonald, R.K. Chanana, A. Weller, S.T. Pantelides, L.C. Feldman, O.W. Holland, M.K. Das, and J.W. Palmour: IEEE Elec. Dev. Lett., Vol. 22: 4 (2001), p.176.
2. D. Habersat, A.J. Lelis, G. Lopez, J. McGarrity, and F.B. McLean, these Proceedings.
3. K.C. Chang, N.T. Nuhfer, L.M. Porter, and Q. Wahab: Appl. Phys. Lett., Vol. 77: 14 (2000), p.2186.
4. G.G. Jernigan, R.E. Stahlbush, M.K. Das, J.A. Cooper, Jr., and L.A. Lipkin: Appl. Phys. Lett., Vol. 74: 10 (1999), p.1448.
5. M.M. Maranowski and J.A. Cooper, Jr.: IEEE Trans. Elec. Dev., Vol. 46: 3 (1999), p.520.
Cited by
45 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献