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Title: Elimination of remnant phases in low-temperature growth of wurtzite ScAlN by molecular-beam epitaxy
Growth of wurtzite Sc x Al 1−x N (x < 0.23) by plasma-assisted molecular-beam epitaxy on c-plane GaN at high temperatures significantly alters the extracted lattice constants of the material due to defects likely associated with remnant phases. In contrast, ScAlN grown below a composition-dependent threshold temperature exhibits uniform alloy distribution, reduced defect density, and atomic-step surface morphology. The c-plane lattice constant of this low-temperature ScAlN varies with composition as expected from previous theoretical calculations and can be used to reliably estimate alloy composition. Moreover, lattice-matched Sc 0.18 Al 0.82 N/GaN multi-quantum wells grown under these conditions display strong and narrow near-infrared intersubband absorption lines that confirm advantageous optical and electronic properties.  more » « less
Award ID(s):
2004462
PAR ID:
10426400
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
132
Issue:
17
ISSN:
0021-8979
Page Range / eLocation ID:
175701
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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