Research On The Doping Properties Of ZnO Transparent Conductive Oxide Thin Films

ZnO is a new type ?-? wide direct bandgap compound semiconductors.ZnO-TCO is thought to have poential value to replace ITO and FTO using in solar cell front rlrctrode,because of its low-cost,environmental protection and stable performance.At present,the world has set off a wave of ZnO thin films.This paper main studied element doped properties of ZnO films,The main work includes:the Li,W co-doped ZnO(LWZO)films were prepared radio frequency magnetron sputtering technology by different sputtering performance;AZO films and Li,Mg co-doped zinc oxide transparent conductive films were prepared by the sol-gel method.The LWZO films growth were perpormed using radio frequency magnetron sputtering technology on quartz glass substrates.The ZnO ceramic target was doped 2at%Li and 1.5 at%W.First,we have explored layer growth orthogonal experiment by orthogonal experiment:sputtering power 200W,distance between target and substrate 55mm,substrate temperature 100 0C and bisa voltage 90V.After that,we modulated doping on the basis of the optimum(sputtering power,for example,the whole process is divided into two parts,first low-power sputtering 15mins,and then continue to increase the power of the sputtering 15mins,other sputtering conditions remain at optimum parameters,and so on),studied the film structure properties,optical properties and electrical properties of different sputtering power,distance between target and substrate,substrate temperature and bias voltage.The results showed that:all samples' X-ray diffraction spectra are present main diffraction(101)peak and high grow perferentially(101)direction.The best of conductivity of the sample is made under for the preparation of a sputtering power out,first its modulation doping process is in the sputtering power 300W sputtered 15mins,then increase the power to 350W sputtering 15mins(abbreviated process conditions for 300W/350W)and resistivity reached 1.1×10-3cm;the best optical properties of the samples are from the beginning of the process conditions for 15mins not joined bias,after 15mins adding bias 90V(referred to 0V/90V),beside,visible-the average near-infrared light is transmittance up to 96%.The ZnO films prepared by sol-gel method and explore the effect of different morphologies Li.Mg and Al doped the number of spin-coating on microstructure structural,SEM and UV optical of ZnO thin films.The results show that:(1)ZnO doped Li,Mg films are showing C-axis preferred orientation,the particle size is larger than the undoped;different Li,Mg concentrations of ZnO films has impact on transmittance of thin films,the highest transmittance of the film is 1:1 of concentration ratio.Therefore,the band gap have larger than undoped thin films and all of then get some broadening.(2)AZO thin-film crystalline quality,hexagonal structure,and height preferred(002)orientation is better than less layers.AZO films are 90%transmittancein on the visible light.