Analysis of 3-Dimensional 4H-SiC MOS Capacitors Grown by Atomic Layer Deposition of Al2O3

Idris, M.I.; Wright, N.G.; Horsfall, A.B.

Abstract

3-Dimensional 4H-SiC metal-oxide-semiconductor capacitors have been fabricated to determine the effect of the sidewall on the characteristics of 3-Dimentional gate structures. Al2O3 deposited by Atomic Layer Deposition (ALD) was used as the gate dielectric layer on the trench structure. The 3-D MOS capacitors exhibit increasing accumulation capacitance with excellent linearity as the sidewall area increases, indicating that ALD results in a highly conformal dielectric film. The capacitance – voltage characteristics also show evidence of a second flatband voltage, located at a higher bias than that seen for purely planar devices on the same sample. We also observe that the oxide capacitance of planar and 3-D MOS capacitors increases with temperature. Finally, we have found that the 3-D MOS capacitor has a weaker temperature dependence of flatband voltage in comparison to the conventional planar MOS capacitor due to the incorporation of the (1120) plane in the sidewall.

Citation

Idris, M., Wright, N., & Horsfall, A. (2018). Analysis of 3-Dimensional 4H-SiC MOS Capacitors Grown by Atomic Layer Deposition of Al2O3. Materials Science Forum, 924, 490-493. https://doi.org/10.4028/www.scientific.net/msf.924.490

• Journal Article Type: Article
• Acceptance Date: Mar 7, 2018
• Online Publication Date: Jun 5, 2018
• Publication Date: 2018-06
• Deposit Date: Oct 1, 2018
• Journal: Materials Science Forum
• Print ISSN: 0255-5476
• Electronic ISSN: 1662-9752
• Publisher: Trans Tech Publications
• Peer Reviewed: Peer Reviewed
• Volume: 924
• Pages: 490-493
• DOI: https://doi.org/10.4028/www.scientific.net/msf.924.490