Investigation of Growth Dynamics of Nanostructured Aluminum Doped Zinc Oxide Thin Films Deposited for the Solar Cell Applications

Abstract

Al doped ZnO (AZO) is one of the most promising transparent conducting oxide materials, which widely utilizes as a front contact for the cadmium telluride based thin film solar cells and a working electrode for perovskite solar cells. This research presents the optimization process of the AZO thin films deposited by spray pyrolysis technique at room temperature by studying its structural, morphological and electrical properties at different thicknesses (100, 150, 200, 300 and 400 nm). Obtained results from X-ray diffraction revealed that the degree of crystallinity and the average grain size of the AZO deposited thin films enhance with increasing the thickness. Surface topography and growth behavior of AZO thin films have important role in optimization of optical and electrical properties of these films especially in the solar cell applications. In this research, the atomic force microscopy (AFM) has been used to assess the quantitative parameters related to the surface topography of the films. Obtained results from AFM analysis revealed that the surface topography of AZO deposited samples strongly depend on thickness. Also the electrical characteristics indicate that the thin films have an electrical resistivity of the order of 10−4 Ω cm.