A Study of ZnO Buffer Layer Effect on Physical Properties of ITO Thin Films Deposited on Different Substrates

Document Type : Research Article


1 Faculty of Electrical Engineering, K.N. Toosi University of Technology, Tehran, I.R. IRAN

2 Faculty of Mechanical Engineering, K.N. Toosi University of Technology, Tehran, I.R. IRAN

3 Thin Film Laboratory, ECE Department, University of Tehran, Tehran, I.R. IRAN


The improvement of the physical properties of Indium Tin Oxide (ITO) layers is quite advantageous in photovoltaic applications. In this study the ITO film is deposited by RF sputtering onto p-type crystalline silicon (c-Si) with (100) orientation, multicrystalline silicon (mc-Si), and glass substrates coated with ZnO and annealed in vacuum furnace at 400°C. Electrical, optical, structural and morphological properties of the ITO films were analyzed by four point probe, UV/VIS/IR spectrophotometer, X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM). The quality of films deposited on buffer layer is found to be superior to those grown directly on a substrate. The structural, optical and electrical studies reveal that ZnO buffer layers improve the crystalline quality, optical and electrical properties of ITO thin films.  


Main Subjects

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