The Effect Of Hot-electron On The Properties Of Single Ga-doped ZnO Microwire Based Devices

ZnO material has been a highlight for research in the field of semiconductor optoelectronic devices in recent years.While ZnO films have encountered the bottleneck due to the p-type doping problem,ZnO micro-nano devices have attracted more and more attention due to their flexible structures.In recent years,single ZnO:Ga microwires have vitnessed many breakthroughs in electroluminescence,electrically pumped lasers,heterojunction light-emitting devices,etc.,but they still face some challenges in photodetection,accurate adjustment of central wavelength of electroluminescence and other aspects.At the same time,non-radiative decay of surface plasmons generates hot carriers in metal nanostructures that has been widely applied to enhance the performance of the photovoltaic devices,such as photodetectors and solar cells,and the resonance frequency of gold nanorods surface plasmon can be accurately adjusted by adjusting the length to diameter ratio,and further adjust the performance of semiconductor devices.Encouraged by these results,by building AuNRs@ZnO:Ga devices decorated by gold nanorods with different length to diameter ratios,the impact of hot electron effect on the performance of single ZnO:Ga microwire device has been studied,and the performance of ZnO:Ga microwire based devices have been improved,which provides a solution for the realization of integrated high-performance semiconductor devices.The following results have been achieved in this thesis:(1)By building single AuNRs@ZnO:Ga microwire device,the photodetection of a single ZnO:Ga micronwire device has been realized by the hot electron effect.By comparison,it has been found that the detection ability depends on the surface plasmon resonance frequency of the decorated gold nanoparticles.The mechanism of this phenomenon can be attributed to the injection of hot electrons from the Au nanorods into the adjacent ZnO:Ga microwire conduction band induced by the non-radiative decay of surface plasmons,which provides a solution for the construction of high-performance integrated detectors in the future.(2)By building single AuNRs@ZnO:Ga microwire devices decorated by gold nanorods with different length to diameter ratios,the electroluminescence wavelength of the ZnO:Ga microwire device was accurately controlled from 500 nm to 900 nm by hot electron effect,and the luminescence intensity has been enhanced.In addition,a fluorescent filament light source with tunable wavelength based on single AuNRs@ZnO:Ga microwire as well as a series filament light sources based on ZnO:Ga microwire and AuNRs@ZnO:Ga microwire are also constructed,providing solutions for the realization of integrated multicolor light source and active lighting display devices in the future.(3)The electroluminescence of the n-ZnO:Ga/p-GaN heterojunction device has been enhanced by the introduction of Au nanorods onto the ZnO:Ga microwires.Intense blue electroluminescence has been observed from the device,and the electroluminescence intensity has been enhanced by two times after the decoration of gold nanorods.