Description
GaN-based devices are currently limited by reliability issues such as gate leakage and current collapse, where the mechanisms responsible for degradation are closely related to the electronic surface state configuration. Therefore, understanding the electronic surface state configuration of GaN-based materials will help improve device performance. Since GaN has an inherent polarization, these materials are also subject to a bound polarization charge, which influences the electronic state configuration. In this study, the surface band bending of N-face GaN, Ga-face GaN, and Ga-face AlGaN was measured with x-ray photoemission spectroscopy after various cleaning steps to investigate the effects of the polarization. Despite the different surface bound charge on these materials, similar band bending was observed regardless of the magnitude or direction of the charge. Specifically, the band bending varied from −0.1 eV to 0.9 eV on these samples, which supported the models of a Fermi level pinning state at ∼0.4 eV to 0.8 eV below the conduction band. Based on available literature, we suggest this pinning state is indirectly evident of a nitrogen vacancy or gallium-dangling bond.
Details
Title
- Polarization Effects of GaN and AlGaN: Polarization Bound Charge, Band Bending, and Electronic Surface States
Contributors
- Eller, Brianna S. (Author)
- Yang, Jialing (Author)
- Nemanich, Robert (Author)
- College of Liberal Arts and Sciences (Contributor)
- Department of Physics (Contributor)
Date Created
The date the item was original created (prior to any relationship with the ASU Digital Repositories.)
2014-12-01
Resource Type
Collections this item is in
Identifier
- Digital object identifier: 10.1007/s11664-014-3383-z
- Identifier TypeInternational standard serial numberIdentifier Value0361-5235
- Identifier TypeInternational standard serial numberIdentifier Value1543-186X
Note
- This is the authors' final accepted manuscript. The final publication is available at http://link.springer.com.ezproxy1.lib.asu.edu/article/10.1007/s11664-014-3383-z
Citation and reuse
Cite this item
This is a suggested citation. Consult the appropriate style guide for specific citation guidelines.
Eller, Brianna S., Yang, Jialing, & Nemanich, Robert J. (2014). Polarization Effects of GaN and AlGaN: Polarization Bound Charge, Band Bending, and Electronic Surface States. JOURNAL OF ELECTRONIC MATERIALS, 43(12), 4560-4568. http://link.springer.com.ezproxy1.lib.asu.edu/article/10.1007/s11664-01…