Research For Flexible Zno Based UV PDs On Piezo-phototronic Effect

Along with its flexibility,lightness and portability,flexible UV photodetectors have attracted more and more attention.Zinc oxide?ZnO?-based thin film materials have excellent semiconductor properties,photoexcitation,and piezo-phototronic effect.The construction of flexible ZnO-based UV photodetector on a PET substrate?thin film preparation?device fabrication,and performance control have been studied in detail.The performance regulation of flexible Mg_0.2Zn_0.80 with a larger band gap UV photodetector has been successfully analyzed.The difference between the photoelectric properties of Mg_0.2Zn_0.8O/ZnO/PET and ZnO/Mg_0.2Zn_0.8O/PET devices was also analyzed.The piezoelectric polarization charge on Schottky junctions and homojunction was systematically studied.Through the above research,the regulation mechanism of the UV photodetector carrier transport operation by piezo-phototronic effect was cleared up,which can promotes the performance improvement of ZnO-based devices.The main research results are as follows:?1?The reproducible of ZnO film detector fabricated on flexible PET substrate was studied for the first time,and the responsivity change between after 100 times of tensile reciprocating and initial state was only 1/1000.When applying external stress,responsivity was improved by 320%with tensile strain of 10.99%from 0.06 to 0.19 A/W.The performance of the detector under different sputtering power was studied by three bias.?2?In view of the uncertainty of c-axis orientation of semiconductor films,two sets of flexible Mg_0.2Zn_0.8O ultraviolet detectors were prepared and the carrier separation of piezoelectric polarization charge on the Mg_0.2Zn_0.8O/Au interface was systematically analyzed.And the effect of the extraction process to promote the effective utilize of tensile strain to effectively control the interface performance of piezoelectric devices.The photoelectric performances of the detector at different bias and different interdigital electrode widths were also studied.?3?The flexible Au/Mg_0.2Zn_0.8O/ZnO dual-band and double-junction detector was prepared by radio frequency magnetron sputtering method.When the bias constant and tensile strain was 15%,the peak responsivity of ZnO and Mg_0.2Zn_0.8O films increased by191%and 241%respectively,and the performance of the flexible dual-band detector was effectively regulated.The dual-band detectors was constructed by exchanging ZnO and Mg_0.2Zn_0.8O film sputtering sequence,thereby the photoelectric performance of the detector was compared.