High-Pressure O2 Annealing Enhances the Crystallinity of Ultrawide-Band-Gap Sesquioxides Combined with Graphene for Vacuum-Ultraviolet Photovoltaic Detection

(AlxGa1-x)2O3 is emerging as a promising wide-band-gap sesquioxide for vacuum-ultraviolet (VUV, 10-200 nm) photodetectors and high-power field-effect transistors. However, how the key parameters such as the band gap and crystalline phase of the (AlxGa1-x)2O3-based device vary with stoichiometry has not been explicitly defined, which is due to the unclear underlying mechanism of the Al local coordination environment. In this work, a high-pressure O2 (20 atm) annealing (HPOA) strategy that can significantly improve the crystallinity of β-(AlxGa1-x)2O3 and achieve a tunable optical band gap was proposed, facilitating the revelation of the local structure of Al3+ varying with Al content and the kinetic mechanism of Al3+ diffusion. By combining the as-HPOA-treated single-crystalline β-(Al0.69Ga0.31)2O3 films with p-type graphene (p-Gr), which serves as a transparent conductor, a VUV photovoltaic detector is fabricated, showing an improved photovoltage (0.80 V) and fast temporal response (2.1 μs). All of these findings provide a rewarding and important strategy for enhancing the band-gap tunability of sesquioxides, as well as the flexibility of zero-power-consumption photodetectors.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:13

Enthalten in:

ACS applied materials & interfaces - 13(2021), 14 vom: 14. Apr., Seite 16660-16668

Sprache:

Englisch

Beteiligte Personen:

Li, Titao [VerfasserIn]
Zheng, Wei [VerfasserIn]
Zhu, Siqi [VerfasserIn]
Wang, Fei [VerfasserIn]
Zhu, Yanming [VerfasserIn]
Jia, Lemin [VerfasserIn]
Lin, Zeguo [VerfasserIn]
Huang, Feng [VerfasserIn]

Links:

Volltext

Themen:

Gallium oxide
Journal Article
Photodetector
Sesquioxides
Vacuum-ultraviolet
Wide-band-gap semiconductor

Anmerkungen:

Date Revised 15.04.2021

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acsami.1c00429

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM323429092