Strong geometrical effects in submillimeter selective area growth and light extraction of GaN light emitting diodes on sapphire [electronic resource].
- Washington, D.C. : United States. National Nuclear Security Administration, 2015.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- Article numbers 17,314 : digital, PDF file
- Additional Creators:
- Sandia National Laboratories
United States. National Nuclear Security Administration
United States. Department of Energy. Office of Scientific and Technical Information
- Advanced semiconductor devices often utilize structural and geometrical effects to tailor their characteristics and improve their performance. Our detailed understanding of such geometrical effects in the epitaxial selective area growth of GaN on sapphire substrates is reported here, and we utilize them to enhance light extraction from GaN light emitting diodes. Systematic size and spacing effects were performed side-by-side on a single 2” sapphire substrate to minimize experimental sampling errors for a set of 144 pattern arrays with circular mask opening windows in SiO<sub>2</sub>. We show that the mask opening diameter leads to as much as 4 times increase in the thickness of the grown layers for 20 μm spacings and that spacing effects can lead to as much as 3 times increase in thickness for a 350 μm dot diameter. We also observed that the facet evolution in comparison with extracted Ga adatom diffusion lengths directly influences the vertical and lateral overgrowth rates and can be controlled with pattern geometry. Lastly, such control over the facet development led to 2.5 times stronger electroluminescence characteristics from well-faceted GaN/InGaN multiple quantum well LEDs compared to non-faceted structures.
- Published through SciTech Connect.
Scientific Reports 5 ISSN 2045-2322 AM
Atsunori Tanaka; Renjie Chen; Katherine L. Jungjohann; Shadi A. Dayeh.
- Funding Information:
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