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Title: High‐Performance Solar Blind UV Photodetectors Based on Single‐Crystal Si/β‐Ga 2 O 3 p‐n Heterojunction
Abstract In this study, Si/β‐Ga2O3solar‐blind photodetectors (PDs) have been demonstrated via micro‐transfer printing of a single crystalline Si pillar on β‐Ga2O3. Unlike other previous approaches for β‐Ga2O3based heterojunction, this new single crystalline p‐n Si/β‐Ga2O3heterojunction has a particle‐free heterointerface and does not show any sign of internal strain after the heterogeneous integration that is confirmed by Raman spectroscopy. As a result, PDs exhibit extremely high photoresponsivity (748 A W−1), quantum efficiency (3.67 × 105%), and UV/visible rejection ratio (≈105) under UV light illumination. This result is believed to provide a viable route for the realization of high‐performance solar‐blind photodetection systems, which form some of the most indispensable and important components in high‐performance next‐generation security, biomedical, and environmental monitoring systems. Also, the unique heterogeneous integration method allows us to realize a variety of β‐Ga2O3based heterostructures that can further enhance the optical performances of β‐Ga2O3based PDs.  more » « less
Award ID(s):
1809077
PAR ID:
10363826
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Technologies
Volume:
6
Issue:
6
ISSN:
2365-709X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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