| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1553498 | Superlattices and Microstructures | 2014 | 10 Pages |
Abstract
Composite HfO2/Al2O3-dielectric In0.2Ga0.8As/Al0.24Ga0.76As metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) by using RF sputtering/ozone water oxidization, respectively, are investigated. In comparison with a conventional Schottky-gate device on the same epitaxial structure, an Al2O3 liner was chemically formed for the present MOS-HEMT to improve interfacial quality and decrease gate leakages. Moreover, a high-k HfO2 layer was further deposited on the Al2O3 liner to enhance the gate modulation capability. The present MOS-HEMT with the devised HfO2/Al2O3 dielectric stack has demonstrated excellent switching characteristics, including superior subthreshold slope (S.S.) of 70Â mV/dec and high drain-source current (IDS) on-off ratio of up to 6 orders. Improved direct-current (DC), radio-frequency (RF), and high-temperature device performances of the present design are also comprehensively studied in this work.
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Ching-Sung Lee, Yu-Hao Liao, Bo-Yi Chou, Han-Yin Liu, Wei-Chou Hsu,