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Title: Structural and electronic properties of NbN/GaN junctions grown by molecular beam epitaxy
We report the structural and electronic properties of NbN/GaN junctions grown by plasma-assisted molecular beam epitaxy. High crystal-quality NbN films grown on GaN exhibit superconducting critical temperatures in excess of 10 K for thicknesses as low as 3 nm. We observe that the NbN lattice adopts the stacking sequence of the underlying GaN and that domain boundaries in the NbN thereby occur at the site of atomic steps in the GaN surface. The electronic properties of the NbN/GaN junction are characterized using Schottky barrier diodes. Current–voltage–temperature and capacitance–voltage measurements are used to determine the Schottky barrier height of the NbN/GaN junction, which we conclude is ∼1.3 eV.  more » « less
Award ID(s):
1719875
PAR ID:
10411699
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
APL Materials
Volume:
10
Issue:
5
ISSN:
2166-532X
Page Range / eLocation ID:
051103
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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