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Title: Threshold voltage control with high-temperature gate-oxide annealing in ultrawide bandgap AlGaN-channel MOSHFETs
Abstract We report threshold voltage (VTH) control in ultrawide bandgap Al0.4Ga0.6N-channel metal oxide semiconductor heterostructure field-effect transistors using a high-temperature (300 °C) anneal of the high-kZrO2gate-insulator. Annealing switched the polarity of the fixed charges at the ZrO2/AlGaN interface from +5.5 × 1013cm−2to −4.2 × 1013cm−2, pinningVTHat ∼ (−12 V), reducing gate leakage by ∼103, and improving subthreshold swing 2× (116 mV decade−1). It also enabled the gate to repeatedly withstand voltages from −40 to +18 V, allowing the channel to be overdriven doubling the peak currents to ∼0.5 A mm−1.  more » « less
Award ID(s):
1831954
PAR ID:
10483529
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
The Japan Society of Applied Physics
Date Published:
Journal Name:
Applied Physics Express
Volume:
15
Issue:
10
ISSN:
1882-0778
Page Range / eLocation ID:
104001
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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