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Title: Epitaxial Sc x Al 1− x N on GaN exhibits attractive high-K dielectric properties

Epitaxial ScxAl1−xN thin films of ∼100 nm thickness grown on metal polar GaN substrates are found to exhibit significantly enhanced relative dielectric permittivity (εr) values relative to AlN. εrvalues of ∼17–21 for Sc mole fractions of 17%–25% ( x = 0.17–0.25) measured electrically by capacitance–voltage measurements indicate that ScxAl1−xN has the largest relative dielectric permittivity of any existing nitride material. Since epitaxial ScxAl1−xN layers deposited on GaN also exhibit large polarization discontinuity, the heterojunction can exploit the in situ high-K dielectric property to extend transistor operation for power electronics and high-speed microwave applications.

Authors:
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Award ID(s):
1719875
Publication Date:
NSF-PAR ID:
10366316
Journal Name:
Applied Physics Letters
Volume:
120
Issue:
15
Page Range or eLocation-ID:
Article No. 152901
ISSN:
0003-6951
Publisher:
American Institute of Physics
Sponsoring Org:
National Science Foundation
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