Study On Preparation And Gas-sensing Property Of Zn-Sn-O Thin Films

the current gas sensitive elements are mainly SnO₂、Fe₂O₃、ZnO etc，in the actualApplication,there are still many problems, for example: short service life, high workingtemperature, doped instability, gas sensitive low sensitivity, Poor selectivity, responserecovery time is long and so on, Therefore, by doping with improved gas sensingproperties, the development of new gas sensing materials is necessary. This articlethrough the double target sputtering method on Preparation of Zn-Sn-O film in order toobtain the better performance of the thin film gas sensitive materialThis paper adopts magnetron sputtering equipment, at different oxygen partialpressure, double target sputtering metal Zn and Sn target preparation methods ofpreparing Zn-Sn-O film, film in the air at different annealing temperature, by XRDmeasured the power sputtering thin film phase. After analysis, found in the Sn targetsputtering power as70W, Zn DC sputtering target material power to115W obtained apure ZnSnO₃. Preparing the film the other parameters: the target substrate spacing of6.5cm, argon and oxygen ratio is23:8, the working gas pressure is2.0Pa, the sputteringtime of30minutes. Sn40W,60W,80W sputtering thin film of Zn-Sn-O ZnSnO₃andSnO₂two components; Sn50W the preparation of thin film with SnO, SnO₂andZnSnO₃three components.Study of different sputtering power for the preparation of Zn-Sn-O films on H₂,LPG and C₂H₅OH gas sensitive properties, analyzed the working temperature,sensitivity, response time and recovery time. Single component ZnSnO₃film at350℃,200ppm C₂H₅OH reached30of the resistive sensitivity, and can detect the10ppmlow concentration of C₂H₅OH gas, response time and recovery time is about10S, gassensitive properties of good stability, has good selectivity and so on, can be preparedC₂H₅OH gas sensor sensitive material. Single component ZnSnO₃film at320℃,2000ppm H₂reached5.1sensitivity, response time and recovery time of about25S.Sn40W sputtering Zn-Sn-O films at380℃for2000ppm LPG gas sensitivity can reach8.08, response time and recovery time are respectively70s and38s. The final analysis of ZnSnO₃thin film gas sensitive mechanism of the gas sensorand the prospects of the future research.