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Title: Impact of Solid-State Charge Injection on Spectral Photoresponse of NiO/Ga2O3 p–n Heterojunction
Forward bias hole injection from 10-nm-thick p-type nickel oxide layers into 10-μm-thick n-type gallium oxide in a vertical NiO/Ga2O3 p–n heterojunction leads to enhancement of photoresponse of more than a factor of 2 when measured from this junction. While it takes only 600 s to obtain such a pronounced increase in photoresponse, it persists for hours, indicating the feasibility of photovoltaic device performance control. The effect is ascribed to a charge injection-induced increase in minority carrier (hole) diffusion length (resulting in improved collection of photogenerated non-equilibrium carriers) in n-type β-Ga2O3 epitaxial layers due to trapping of injected charge (holes) on deep meta-stable levels in the material and the subsequent blocking of non-equilibrium carrier recombination through these levels. Suppressed recombination leads to increased non-equilibrium carrier lifetime, in turn determining a longer diffusion length and being the root-cause of the effect of charge injection.  more » « less
Award ID(s):
2310285
PAR ID:
10509548
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Condensed Matter
Volume:
8
Issue:
4
ISSN:
2410-3896
Page Range / eLocation ID:
106
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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