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Title: 4.4 kV β-Ga 2 O 3 MESFETs with power figure of merit exceeding 100 MW cm −2
Abstract β -Ga 2 O 3 metal–semiconductor field-effect transistors are realized with superior reverse breakdown voltages ( V BR ) and ON currents ( I DMAX ). A sandwiched SiN x dielectric field plate design is utilized that prevents etching-related damage in the active region and a deep mesa-etching was used to reduce reverse leakage. The device with L GD = 34.5 μ m exhibits an I DMAX of 56 mA mm −1 , a high I ON / I OFF ratio >10 8 and a very low reverse leakage until catastrophic breakdown at ∼4.4 kV. A power figure of merit (PFOM) of 132 MW cm −2 was calculated for a V BR of ∼4.4 kV. The reported results are the first >4 kV class Ga 2 O 3 transistors to surpass the theoretical unipolar FOM of silicon.  more » « less
Award ID(s):
2019749
PAR ID:
10444752
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Express
Volume:
15
Issue:
6
ISSN:
1882-0778
Page Range / eLocation ID:
061001
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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