Growth of transparent nc-InGaO3 (ZnO)2 thin films with indium mol ratios using solution process

The effect of indium mol ratio on nanocrystalline (nc)- InGa O3 (ZnO)2 thin films prepared by solution was investigated with structural properties. The size of nanocrystallines tended to increase up to 120 nm with an optimized indium mol ratio after second postannealing at 700°C for 10 s with three cycles. The shape of the nanocrystallines and their growth were determined by the indium mol ratio. The main (008) growth direction, which had a columnar structure, could be retarded by a high indium mol ratio, which could generate the (100) direction growth. After postannealing, the films had with less oxygen deficiency and main stoichometric oxygen bound with metal (In, Ga, and Zn). The growth of nanocrystallines during the second postannealing from small grains with random orientation to large grains with well-aligned orientation could be explained by a self-solid phase reaction with decomposition and combination of precursor without any additional epitaxial layer. It implied that the crystallinity of nc-InGa O3 (ZnO)2 thin films was strongly dependent on process parameters such as temperature and component mol ratio. © 2008 The Electrochemical Society.