Structural and Electrical Properties of Na₊-doped ZnO Thin Films

Na+-doped ZnO thin films were prepared on Si〈100〉 substrate by sol-gel method using zinc acetate and sodium carbonate as starting materials,the doping amount is 0,0.018,0.036,0.045,0.063 and 0.090 mol/L,respectively.The phase structural characteristics and electrical properties,including the cell size of ZnO lattice,the conducting type as well as the Raman shift,of the so-obtained films were investigated by XRD,SEM,Raman scattering analysis and four-point probe van der Pauw method.The results showed that Na+ can occupy the Zn2+ sites of ZnO lattice,leading to the enlargement of ZnO cell.After doping Na+,the conductive type of ZnO films changed to p from n-type,and the resistivity,Hall mobility,and the hole concentration of the film with 0.045 mol/L Na+ were 75.7 Ω·cm and 2.955×1017/cm3,respectively.