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Title: Wide‐Bandgap Nickel Oxide with Tunable Acceptor Concentration for Multidimensional Power Devices
Multidimensional power devices can achieve performance beyond conventional limits by deploying charge‐balanced p‐n junctions. A key obstacle to developing such devices in many wide‐bandgap (WBG) and ultra‐wide bandgap (UWBG) semiconductors is the difficulty of native p‐type doping. Here the WBG nickel oxide (NiO) as an alternative p‐type material is investigated. The acceptor concentration (NA) in NiO is modulated by oxygen partial pressure during magnetron sputtering and characterized using a p‐n+heterojunction diode fabricated on gallium oxide (Ga2O3) substrate. Capacitance and breakdown measurements reveal a tunableNAfrom < 1018 cm−3to 2×1018 cm−3with the practical breakdown field (EB) of 3.8 to 6.3 MV cm−1. ThisNArange allows for charge balance to n‐type region with reasonable process latitude, andEBis high enough to pair with many WBG and UWBG semiconductors. The extractedNAis then used to design a multidimensional Ga2O3diode with NiO field‐modulation structure. The diodes fabricated with two differentNAboth achieve 8000 V breakdown voltage and 4.7 MV cm−1average electric field. This field is over three times higher than the best report in prior multi‐kilovolt lateral devices. These results show the promise of p‐type NiO for pushing the performance limits of power devices.  more » « less
Award ID(s):
2230412 2036740
PAR ID:
10545891
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Electronic Materials
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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