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Epitaxial Sc_{x}Al_{1−}_{x}N thin films of ∼100 nm thickness grown on metal polar GaN substrates are found to exhibit significantly enhanced relative dielectric permittivity (ε_{r}) values relative to AlN. ε_{r}values of ∼17–21 for Sc mole fractions of 17%–25% ( x = 0.17–0.25) measured electrically by capacitance–voltage measurements indicate that Sc_{x}Al_{1−}_{x}N has the largest relative dielectric permittivity of any existing nitride material. Since epitaxial Sc_{x}Al_{1−}_{x}N layers deposited on GaN also exhibit large polarization discontinuity, the heterojunction can exploit the in situ highK dielectric property to extend transistor operation for power electronics and highspeed microwave applications.
 Award ID(s):
 1719875
 Publication Date:
 NSFPAR ID:
 10366316
 Journal Name:
 Applied Physics Letters
 Volume:
 120
 Issue:
 15
 Page Range or eLocationID:
 Article No. 152901
 ISSN:
 00036951
 Publisher:
 American Institute of Physics
 Sponsoring Org:
 National Science Foundation
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