The Studies On ZnO Ultraviolet Light Detection Device

The photodetector is a device that uses the photoelectric effect to convert optical signals into electrical signals.Ultraviolet(UV)photodetectors are photodetectors working in the ultraviolet band,which have a wide range of uses in military and civilian fields,such as missile guidance,space station docking,environmental monitoring,flame sensing,chemical / biological analysis.Nowadays,UV photodetectors have realized a variety of functional detections,such as UV radiation dosimeters for detecting UV radiation levels and high-performance photodetectors for detecting solar blind areas and UV areas.Since functional detection is significance for the practical application of ultraviolet photodetectors,the research on the functionalities of ultraviolet photodetectors has also been paid inceasingly attention.Zinc oxide(Zn O)has a forbidden band width of 3.37 e V.As a wide forbidden band semiconductor material with excellent photoelectric performance,it is often used in the field of ultraviolet photodetection.The current research on Zn O-based ultraviolet photodetector devices has made some progress,but further research is still needed for its various functional detections.This thesis is based on the functional research of Zn Obased ultraviolet light detector,and the following research results have been achieved:(1)The Zn O microwire ultraviolet radiation dosimeter is proposed,designed and proved based on the continuous photoconductivity effect in the Zn O microwire.Due to the continuous photoconductivity effect,the photocurrent generated in the Zn O microwire depends on the accumulated ultraviolet radiation.Thus,the photocurrent can be used to determine the amount of UV accumulation.In addition,the ultraviolet radiation dosimeter is not affected by visible light and shows a high photoconductance gain of 2654 with a relative error of about 10%.This ultraviolet radiation dosimeter with electrical signal output can be reused,be integrated with other electronic devices and be extended new fields of application for the continuous photoconductive effect.(2)Prepare water-soluble Zn O quantum dots and construct a heterojunction with graphene,and prepare ultraviolet-visible resolvable Zn O quantum dot/graphene broadband photodetector.The photodeterctor has a positive photoconductive effect under ultraviolet light and a negative photoconductive effect under visible light.Thus,it can detect and distinguish between ultraviolet and visible light,and provides a new idea for ultraviolet photoelectric function detection technology.