High-performance UV Detectors Based On 1D/2D In GaO₃（ZnO）_n Superlattice Nanomaterials

In recent years,ultraviolet photodetectors are wildly applied in the fields of astronomy,environmental monitoring,advanced communications and radiation detection,getting more and more attention.InGaO₃（ZnO）_n superlattice nanomaterials have become a very promising new generation of optoelectronic materials with high carrier mobility,high carrier separation efficiency,high transmittance and other characteristics.However,InGaO₃（ZnO）_n superlattice nanomaterials fabrication generally request expensive equipment and complex preparation processes.Currently,research on InGaO₃（ZnO）_n superlattice UV detectors is only limited to one-dimensional（1D）single nanowire and two-dimensional（2D）amorphous thin-film transistor structures,while the low-cost and large-scale synthesis method of vertically aligned nanowire arrays and the evaluation of their UV detection performance,which are more promising for industrial applications,remains scarce.Meanwhile,the partial growth mechanism of 2D InGaO₃（ZnO）_n superlattice films and the optimization of device structure still need further study.Therefore,this thesis is centered on the new synthesis method of1D/2D InGaO₃（ZnO）_n superlattice nanomaterials,material growth mechanism,preparation and performance of UV detector devices as follows:（1）ZnO nanowire arrays were prepared using a chemical vapor deposition（CVD）method,based on which 1D InGaO₃（ZnO）_n superlattice nanowire arrays were successfully synthesized through annealing precursor coated as grown.The magnitude of the superlattice period n value was adjusted by changing the precursor concentration,and the related characterization was performed.（2）A UV detector based on InGaO₃（ZnO）_n superlattice nanowire arrays with top-bottom electrode structure was designed and fabricated,and the preparation parameters of PMMA sacrificial layer filling,plasma etching,electrode sputtering and other processes were screened.Through the UV detection performance test,the optimization of the device structure is proposed for the problems of low effective light receiving area and unstable photocurrent transmission.（3）A new MSM structure（metal-semiconductor-metal）structure 1D InGaO₃（ZnO）_nsuperlattice nanowire arrays UV detector was prepared by improving the device structure,which and the device exhibited good test stability and repeatability with a maximum photocurrent of 5.72μA and a response speed of 0.25 s.（4）2D flexible InGaO₃（ZnO）_n superlattice nanoparticle thin film UV detectors were designed and prepared,and the preparation parameters such as solution solubility,spin-coating speed,and spin-coating times were discussed.On this basis,the effects of parameters such as film morphology,external bias,and electrode spacing on device performance are investigated.（5）Dense ZnO films with selective orientation were prepared by radio frequency magnetron sputtering（RFPVD）,and 2D polycrystalline quasi-directional InGaO₃（ZnO）_nsuperlattice films were prepared by sol-gel method,and the growth mechanism of films was investigated by AFM and KPFM characterization.2D thin film UV detector devices with MSM structure were prepared to study the changes of UV detection performance at different growth stages,and the corresponding explanations were made from the perspectives of film morphology,surface potential and material work function.