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Title: Transport properties of polarization-induced 2D electron gases in epitaxial AlScN/GaN heterojunctions
AlScN is attractive as a lattice-matched epitaxial barrier layer for incorporation in GaN high electron mobility transistors due to its large dielectric constant and polarization. The transport properties of polarization-induced two-dimensional (2D) electron gas of densities of [Formula: see text]/cm 2 formed at the AlScN–GaN interface is studied by Hall-effect measurements down to cryogenic temperatures. The 2D electron gas densities exhibit mobilities limited to ∼300 cm 2 /V s down to 10 K at AlScN/GaN heterojunctions. The insertion of a ∼2 nm AlN interlayer boosts the room temperature mobility by more than five times from ∼300 cm 2 /V s to [Formula: see text] cm 2 /V s, and the 10 K mobility by more than 20 times to ∼6980 cm 2 /V s at 10 K. These measurements provide guidelines to the limits of electron conductivities of these highly polar heterostructures.  more » « less
Award ID(s):
1719875
PAR ID:
10411970
Author(s) / Creator(s):
; ; ; ; ; ; ;  ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
19
ISSN:
0003-6951
Page Range / eLocation ID:
192101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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