Single-Crystalline All-Oxide α-γ-β Heterostructures for Deep-Ultraviolet Photodetection

Recent advancements in gallium oxide (Ga2O3)-based heterostructures have allowed optoelectronic devices to be used extensively in the fields of power electronics and deep-ultraviolet photodetection. While most previous research has involved realizing single-crystalline Ga2O3 layers on native substrates for high conductivity and visible-light transparency, presented and investigated herein is a single-crystalline β-Ga2O3 layer grown on an α-Al2O3 substrate through an interfacial γ-In2O3 layer. The single-crystalline transparent conductive oxide layer made of wafer-scalable γ-In2O3 provides high carrier transport, visible-light transparency, and antioxidation properties that are critical for realizing vertically oriented heterostructures for transparent oxide photonic platforms. Physical characterization based on X-ray diffraction and high-resolution transmission electron microscopy imaging confirms the single-crystalline nature of the grown films and the crystallographic orientation relationships among the monoclinic β-Ga2O3, cubic γ-In2O3, and trigonal α-Al2O3, while the elemental composition and sharp interfaces across the heterostructure are confirmed by Rutherford backscattering spectrometry. Furthermore, the energy-band offsets are determined by X-ray photoelectron spectroscopy at the β-Ga2O3/γ-In2O3 interface, elucidating a type-II heterojunction with conduction- and valence-band offsets of 0.16 and 1.38 eV, respectively. Based on the single-crystalline β-Ga2O3/γ-In2O3/α-Al2O3 all-oxide heterostructure, a vertically oriented DUV photodetector is fabricated that exhibits a high photoresponsivity of 94.3 A/W, an external quantum efficiency of 4.6 × 104%, and a specific detectivity of 3.09 × 1012 Jones at 250 nm. The present demonstration lays a strong foundation for and paves the way to future all-oxide-based transparent photonic platforms.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:12

Enthalten in:

ACS applied materials & interfaces - 12(2020), 48 vom: 02. Dez., Seite 53932-53941

Sprache:

Englisch

Beteiligte Personen:

Li, Kuang-Hui [VerfasserIn]
Kang, Chun Hong [VerfasserIn]
Min, Jung-Hong [VerfasserIn]
Alfaraj, Nasir [VerfasserIn]
Liang, Jian-Wei [VerfasserIn]
Braic, Laurentiu [VerfasserIn]
Guo, Zaibing [VerfasserIn]
Hedhili, Mohamed Nejib [VerfasserIn]
Ng, Tien Khee [VerfasserIn]
Ooi, Boon S [VerfasserIn]

Links:

Volltext

Themen:

All-oxide photonics
Aluminum oxide (Al2O3)
Deep-ultraviolet
Gallium oxide (Ga2O3)
Indium oxide (In2O3)
Journal Article
Photodetectors

Anmerkungen:

Date Revised 05.04.2023

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acsami.0c15398

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM317704656