Effect of substrate on ZnO thin films grown by SILAR method

Zinc oxide (ZnO) thin films were grown on three kinds of substrates (copper, silicon and glass) by the SILAR method. The solution was prepared by using zinc sulphate ZnSO₄ and ammonia NH₃. And for rinsing, we heated the distilled water at the temperature 80°C. The nature of substrate was found to have effect on the crystal structure, morphology and optical properties of the resultant ZnO thin films. For the X-ray measurements results, it can be see that growth orientation of the resultant ZnO thin films deposited on copper, silicon and glass substrates are (101), (103) and (002) respectively. The SEM results showed that the ZnO grains deposited on copper substrate takes the hexagonal structure, those deposited on silicon substrate takes the spindles shape, and who are deposited on glass substrate takes the forms of small flowers and prisms. XPS measurements were carried out, the result showed that the ZnO thin films grown on three kinds of substrates had different XPS behaviours. And one grown on the glass substrate had the best performance, and his gap close to 3.2 eV.