Investigation of characteristics of ZnO:Ga nanocrystalline thin films with varying dopant content

In this study, undoped and Ga doped ZnO thin films were synthesized by the sol-gel spin coating technique. The effect of Ga contribution on the structural, morphological and optical properties of the ZnO thin films was examined. XRD results showed that all films had a hexagonal wurtzite crystal structure with polycrystalline nature. The intensity of the (002) peak changed with the variable Ga content. The scanning electron microscopy (SEM) results revealed that the surface morphology of the ZnO thin films was affected by Ga content. Moreover, it consisted of nanorods as a result of the increased function of the Ga content. Additionally, the presence of Ga contributions was evaluated by energy dispersive x-ray (EDX) measurements. Although the transparency and the optical band gap of the ZnO thin films increased with Ga contribution, Urbach energy values decreased from 221 meV to 98 meV. In addition, these steepness parameters increased with the increased Ga content from 0% to 6%. The correlation between structural and optical properties was investigated and significant consistency was found.