Study Of Structural And Varistor Of ZnO Thin Films Prepared By Sol-gel Technique

ZnO is a novel II～VI family compound. It is a wide direct-gap semiconductor and has great uses in information age.Following the development of VLSI,ZnO thin films attracts much attention in varistors research field.In the paper, A Series of ZnO thin films were prepared on Si(111)in the sol-gel process. Applying the theory of orthogonal-design, the technological conditions were optimized after investigation and analysis of the samples by XRD and have a touch to preparing process of ZnO thin films varistors. The results revealed that, for preparing highly oriented along c-axis and films, the optimized growing parameters at Si (111) substrate were: ZnO:0.35mol/l(Zn²⁺),50℃(agin temperature),200℃(preheating temperature),650℃(annealing temperature)and two hours(heating time) ; for ZnO varistors property thin films, the optimized growing parameters were: Bi₂O₃ : Sb₂O₃ : Co₂O₃ : MnO₂ : Cr₂O₃ : Ni₂O₃ = 1: 2: 1: 1: 1: 1 (impurity),Zn²⁼ : impurity concentration = 97 mol%/l : 3 mol%/l,750℃(annealing temperature) ; AZO: impurity concentration is 0.001-0.1 mol/l.The result:αof ZnO thin films is 8.3～16.12,U_1MA is near 20V.