Loading…
Engineering Epitaxial Gamma-Al-2O-3 Gate Dielectric Films on 4H-SiC
The formation of epitaxial {gamma}-Al{sub 2}O{sub 3} thin films on 4H-SiC was found to be strongly dependent on the film thickness. An abrupt interface was observed in films up to 200 {angstrom} thick with an epitaxial relationship of {gamma}-Al{sub 2}O{sub 3}(111) {parallel} 4H-SiC(0001) and {gamma...
Saved in:
Published in: | Journal of applied physics 2009-04, Vol.102 (10) |
---|---|
Main Authors: | , , , , , , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | The formation of epitaxial {gamma}-Al{sub 2}O{sub 3} thin films on 4H-SiC was found to be strongly dependent on the film thickness. An abrupt interface was observed in films up to 200 {angstrom} thick with an epitaxial relationship of {gamma}-Al{sub 2}O{sub 3}(111) {parallel} 4H-SiC(0001) and {gamma}-Al{sub 2}O{sub 3}(4{bar 4}0) {parallel} 4H-SiC(11{bar 2}0). The in-plane alignment between the film and the substrate is nearly complete for {gamma}-Al{sub 2}O{sub 3} films up to 115 {angstrom} thick, but quickly diminishes in thicker films. The films are found to be slightly strained laterally in tension; the strain increases with thickness and then decreases in films thicker than 200 {angstrom}, indicating strain relaxation which is accompanied by increased misorientation. By controlling the structure of ultrathin Al{sub 2}O{sub 3} films, metal-oxide-semiconductor capacitors with Al{sub 2}O{sub 3} gate dielectrics on 4H-SiC were found to have a very low leakage current density, suggesting suitability of Al{sub 2}O{sub 3} for SiC device integration. |
---|---|
ISSN: | 0021-8979 1089-7550 |