Self-Assembled Al Nanostructure/ZnO Quantum Dot Heterostructures for High Responsivity and Fast UV Photodetector

Sisi Liu; Ming-Yu Li; Jianbing Zhang; Dong Su; Zhen Huang; Sundar Kunwar; Jihoon Lee

doi:10.1007/s40820-020-00455-9

Self-Assembled Al Nanostructure/ZnO Quantum Dot Heterostructures for High Responsivity and Fast UV Photodetector

Nanomicro Lett. 2020 May 22;12(1):114. doi: 10.1007/s40820-020-00455-9.

Authors

Sisi Liu¹, Ming-Yu Li², Jianbing Zhang¹, Dong Su¹, Zhen Huang³, Sundar Kunwar⁴, Jihoon Lee^{4

5}

Affiliations

¹ School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
² School of Science, Wuhan University of Technology, Wuhan, 430070, People's Republic of China. mingyuli.oliver@gmail.com.
³ Wuhan National Laboratory for Optoelectronics (WNLO) and School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
⁴ College of Electonics and Information, Kwangwoon University, Nowon-gu, Seoul, 01897, Republic of Korea.
⁵ Institute of Nanoscale Science and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA.

Abstract

Highlights:

High performance Al nanostructures/ZnO quantum dots heterostructure photodetectors with a controllable geometry of the Al nanostructures are demonstrated.
Light utilization of the photoactive layers is significantly boosted with the Al nanostructures.
The light confinement effect is inherently determined by the geometries of the Al nanostructures.

Abstract: Light confinement induced by spontaneous near-surface resonance is inherently determined by the location and geometry of metallic nanostructures (NSs), offering a facile and effective approach to break through the limitation of the light-mater interaction within the photoactive layers. Here, we demonstrate high-performance Al NS/ZnO quantum dots (Al/ZnO) heterostructure UV photodetectors with controllable morphologies of the self-assembled Al NSs. The Al/ZnO heterostructures exhibit a superior light utilization than the ZnO/Al heterostructures, and a strong morphological dependence of the Al NSs on the optical properties of the heterostructures. The inter-diffusion of Al atoms into ZnO matrixes is of a great benefit for the carrier transportation. Consequently, the optimal photocurrent of the Al/ZnO heterostructure photodetectors is significantly increased by 275 times to ~ 1.065 mA compared to that of the pristine ZnO device, and an outstanding photoresponsivity of 11.98 A W⁻¹ is correspondingly achieved under 6.9 mW cm⁻² UV light illumination at 10 V bias. In addition, a relatively fast response is similarly witnessed with the Al/ZnO devices, paving a path to fabricate the high-performance UV photodetectors for applications.

Electronic supplementary material: The online version of this article (10.1007/s40820-020-00455-9) contains supplementary material, which is available to authorized users.

Keywords: Al/ZnO heterostructure photodetectors; Plasmonic enhancement; Self-assembled Al nanostructures; ZnO quantum dots.