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Title: Thermal Stability of Transparent ITO/n-Ga 2 O 3 /n+-Ga 2 O 3 /ITO Rectifiers
The thermal stability of n/n + β -Ga 2 O 3 epitaxial layer/substrate structures with sputtered ITO on both sides to act as rectifying contacts on the lightly doped layer and Ohmic on the heavily doped substrate is reported. The resistivity of the ITO deposited separately on Si decreased from 1.83 × 10 −3 Ω.cm as-deposited to 3.6 × 10 −4 Ω.cm after 300 °C anneal, with only minor reductions at higher temperatures (2.8 × 10 −4 Ω.cm after 600 °C anneals). The Schottky barrier height also decreased with annealing, from 0.98 eV in the as-deposited samples to 0.85 eV after 500 °C annealing. The reverse breakdown voltage exhibited a negative temperature coefficient of −0.46 V.C −1 up to an annealing temperature of 400 °C and degraded faster at higher temperatures. Transmission Electron Microscopy showed significant reaction at the ITO and Ga 2 O 3 interface above 300 °C, with a very degraded contact stack after annealing at 500 °C.  more » « less
Award ID(s):
2015795
NSF-PAR ID:
10318497
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
ECS Journal of Solid State Science and Technology
Volume:
10
Issue:
11
ISSN:
2162-8769
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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