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Title: β -Ga 2 O 3 FinFETs with ultra-low hysteresis by plasma-free metal-assisted chemical etching
In this work, β-Ga 2 O 3 fin field-effect transistors (FinFETs) with metalorganic chemical vapor deposition grown epitaxial Si-doped channel layer on (010) semi-insulating β-Ga 2 O 3 substrates are demonstrated. β-Ga 2 O 3 fin channels with smooth sidewalls are produced by the plasma-free metal-assisted chemical etching (MacEtch) method. A specific on-resistance (R on,sp ) of 6.5 mΩ·cm 2 and a 370 V breakdown voltage are achieved. In addition, these MacEtch-formed FinFETs demonstrate DC transfer characteristics with near zero (9.7 mV) hysteresis. The effect of channel orientation on threshold voltage, subthreshold swing, hysteresis, and breakdown voltages is also characterized. The FinFET with channel perpendicular to the [102] direction is found to exhibit the lowest subthreshold swing and hysteresis.  more » « less
Award ID(s):
1809946 1810041
NSF-PAR ID:
10377761
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
5
ISSN:
0003-6951
Page Range / eLocation ID:
052102
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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