Properties of ZnO thin films by the ultrasonic spray pyrolysis technique

We have designed an ultrasonic spray pyrolysis system for deposition of ZnO thin films and determined the optimal conditions for deposition of the films. Through experiments to check the effect of various deposition conditions for deposition of the films. Through experiments to check the effect of various deposition condition, we have found that the zinc acetate solution can provide good ZnO films at the substrate temperature of 420[℃], the zinc acetate solution of 0.05 mole doped by 20 atomic percent of LiCL. Further, the resistivity of ZnO films has also increased to 107[Ω.cm] through the annealing under the oxygen environment. Optimal substrate rotation rate and nozzle tilting angle have also been determined to improve the uniformity of the film. ZnO thin films deposited with the conditions show good thickness uniformity over 4'' wafer, and good c-axis orientation.