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Title: Defect Characterization, Imaging, and Control in Wide Band Gap Semiconductors and Devices
Wide-bandgap semiconductors are now leading the way to new physical phenomena and device applications at nanoscale dimensions. The impact of defects on the electronic properties of these materials increases as their size decreases, motivating new techniques to characterize and begin to control these electronic states. Leading these advances have been the semiconductors ZnO, GaN, and related materials. This paper highlights the importance of native point defects in these semiconductors and describes how a complement of spatially localized surface science and spectroscopy techniques in three dimensions can characterize, image, and begin to control these electronic states at the nanoscale. A combination of characterization techniques including depth-resolved cathodoluminescence spectroscopy, surface photovoltage spectroscopy, and hyperspectral imaging can describe the nature and distribution of defects at interfaces at both bulk and nanoscale surfaces, their metal interfaces, and inside nanostructures themselves. These features as well as temperature and mechanical strain inside wide-bandgap device structures at the nanoscale can be measured even while these devices are operating. These advanced capabilities enable several new directions for describing defects at the nanoscale, showing how they contribute to device degradation, and guiding growth processes to control them.  more » « less
Award ID(s):
1800130
PAR ID:
10165352
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of electronic materials
Volume:
47
ISSN:
0361-5235
Page Range / eLocation ID:
4980-4986
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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