Interfacial and Electrical Characterization of Atomic-Layer-Deposited HfO[sub 2] Gate Dielectric on High Mobility Epitaxial GaAs/Ge Channel Substrates
| Autor: | B. Z. Wang, S. Y. Chiam, A. S. W. Wong, Dongzhi Chi, J. S. Pan, C. K. Chia, Goutam Kumar Dalapati, Han Gao, M. K. Kumar, Akash Kumar |
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| Rok vydání: | 2010 |
| Předmět: |
Materials science
Renewable Energy Sustainability and the Environment business.industry Annealing (metallurgy) Gate dielectric Equivalent oxide thickness Dielectric Condensed Matter Physics Epitaxy Surfaces Coatings and Films Electronic Optical and Magnetic Materials Atomic layer deposition X-ray photoelectron spectroscopy Gate oxide Materials Chemistry Electrochemistry Optoelectronics business |
| Zdroj: | Journal of The Electrochemical Society. 157:H825 |
| ISSN: | 0013-4651 |
| DOI: | 10.1149/1.3453935 |
| Popis: | Interfacial and electrical properties of atomic-layer-deposited HfO 2 gate dielectric on epitaxial GaAs (epi-GaAs)/Ge and bulk GaAs substrates have been investigated. Atomic layer deposition provides a unique opportunity to integrate high quality gate dielectrics on epi-GaAs. The cross-sectional transmission electron microscopy of a HfO 2 /III-V gate stack shows a similar interfacial layer thickness for HfO 2 on bulk p-GaAs and epi-GaAs substrates. However, X-ray photoelectron spectroscopy shows a Ga oxide-rich interfacial layer after postdeposition annealing at 500°C for films grown on epi-GaAs. Although the epi-GaAs surface is rough with nanoscale features, the electrical properties of the HfO 2 gate dielectric deposited on epi-GaAs are comparable with bulk p-GaAs-based devices. The Au/HfO 2 /epi-GaAs gate stack shows a low frequency dispersion (13%), hysteresis voltage (0.72 V), and a leakage current density of 2.1 X 10 ―3 A cm ―2 at V FB + 1 V (where FB is flatband) for an equivalent oxide thickness of 1.4 nm. |
| Databáze: | OpenAIRE |
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