Fabrication And Field Emission Properties Of ZnO Nanowires

Since its establishment in 1928,field emission theory has always been a major research topic home and has a broad practical appliance prospect.In recent years,researchers around the world are looking for the good field emission cathode material and trying to change its morphology and composition in order to acquire improved field emission performance and stability.ZnO is an important semi-conductor material with good physical property.This nano material has a list of outstangding properties including facial effect,small size effect,quantum size effect and quantunm tunneling effect.Those properties allow it to have a great performance in the field of lighting and electricity science.It is quite suitable to be the material of the negative pole of field emission and is of great value.In this paper,we use sol-gel method and hydrothermal method to conduct growth test of ZnO seed layer and ZnO nanowires on the background of Si.Meanwhile,we use magnetron sputtering to modify the Au on the surface of ZnO nanowires.Then,we research on the field emission function of the sample.The main content of the research is as follows:(1)Using sol-gel method to conduct growth test of ZnO seed layer on the background of Si.Using hydrothermal method to conduct growth test of ZnO nanowires in different concentration levels,different temperature and time durance.Using magnetron sputtering to modify the Au on the surface of ZnO nanowires.(2)Reserach the impact of different variable conditions on the morphology of ZnO nanowires in hydrothermal method.Recording the characterization of the ZnO nanowires sample acquired in different variable conditions by scanning electron microscope(SEM),measuring the aspect ratio of nanowires and analyzing the resulets.The condition for best reaction are: 0.05 mol/L for reaction concentration,6 hours for reaction time and 140 ? for reaction temperature.(3)Studying the impact of different variable conditions to the field emission function of ZnO nanowires.Conducting field emission function test on the sample acquired from the above study.The data collected is in accordance with the traits of F-N characteristic.Therefore,it can be regarded as the field emission phenomen on.The best reaction condition is 0.05 mol/L,6 h,140 ?,which is in concordance with the developing trend of the draw ratio.(4)The field emission properties of Au-modified ZnO nanowires were tested,and then the field emission stability was quantified.The field emission data obtained show that the modification of ZnO nanowires by Au decreases the field emission ability of ZnO nanowires,but improves the field emission stability of ZnO nanowires.When the magnetron sputtering time is 20 s,the fluctuation rate of samples is the smallest,0.73%,and the field emission stability of ZnO nanowires is the best.