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Title: Ohmic co-doped GaN/InGaN tunneling diode grown by MOCVD
Tunnel junctions (TJs) have recently been proposed as a solution for several III-nitride current problems and to enhance new structures. Reported III-nitride TJs grown by metalorganic chemical vapor deposition (MOCVD) resulted in backward diodes with rectifying behavior in forward bias, even with Mg and Si doping in 10 20  cm −3 . This behavior limits applications in several device structures. We report a TJ structure based on p + In 0.15 Ga 0.85 N/n + In 0.05 Ga 0.95 N, where the n-side of the junction is co-doped with Si and Mg and with electron and hole concentrations in the mid-10 19  cm −3 for both the n and p dopants. Co-doping creates deep levels within the bandgap that enhances tunneling under forward biased conditions. The TJ structure was investigated on both GaN substrates and InGaN templates to study the impact of strain on the TJ I–V characteristics. The resulting TJ I–V and resistivities reported indicate the potential for this TJ approach in several device structures based on III-nitrides. We are not aware of any previous MOCVD grown TJs that show Ohmic performance in both forward and reverse biases.  more » « less
Award ID(s):
1833323
PAR ID:
10432048
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
5
ISSN:
0003-6951
Page Range / eLocation ID:
052104
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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