Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1794663 | Journal of Crystal Growth | 2009 | 6 Pages |
Abstract
In this paper, the origin of the conductivity of GaN films grown on ferroelectric materials was investigated using XPS, AES, and XRD analysis tools. Depth profiles confirmed the existence of impurities in the GaN film originating from the substrates. Bonding energy analysis from XPS and AES verified that oxygen impurities from the substrates were the dominant origin of the conductivity of the GaN film. Furthermore, Ga-rich GaN films have a greater chance of enhancing diffusion of lithium oxide from the substrates, resulting in more substrate phase separation and a wider inter-mixed region confirmed by XRD. Therefore, the direct GaN film growth on ferroelectric materials causes impurity diffusion from the substrates, resulting in highly conductive GaN films. Future work needs to develop non-conductive buffer layers for impurity suppression in order to obtain highly resistive GaN films.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Kyoung-Keun Lee, Zhuhua Cai, Katherine Ziemer, William Alan Doolittle,