ZnO UV photodetector with controllable quality factor and photosensitivity

TL;DR

This paper demonstrates that the photosensitivity and quality factor of ZnO nanowire UV photodetectors can be fully tuned via gate voltage, enabling highly selective detection of narrow UV wavelength ranges for advanced applications.

Contribution

It introduces a method to control the Q factor and photosensitivity of ZnO UV photodetectors using gate voltage, achieving tunable wavelength selectivity.

Findings

Photosensitivity and Q factor are tunable by gate voltage.

Detection wavelength range can be narrowed to 3 nm.

Enables detection of elements with sharp luminescence.

Abstract

ZnO nanowires have an enormous potential for applications as ultra-violet (UV) photodetectors. Their mechanism of photocurrent generation is intimately related with the presence of surface states where considerable efforts, such as surface chemical modifications, have been pursued to improve their photodetection capabilities. In this work, we report a step further in this direction demonstrating that the photosensitivity and quality factor (Q factor) of the photodetector are entirely tunable by an applied gate voltage. This mechanism enables UV photodetection selectivity ranging from wavelengths from tens of nanometers (full width at half maximum - FWHM) down to a narrow detection of 3 nm. Such control paves the way for novel applications, especially related to the detection of elements that have very sharp luminescence.