Microstructures Study on Cuprous Oxide Thin Films Deposited on Different Substrates by Using Sol-Gel Technique Dewi Suriyani Che Halin a,1, Haiza Haroon 2,b , Ibrahim Abu Talib 2,c , Abd Razak Daud 2,d and Muhammad Azmi Abd Hamid 2,e 1 School of Materials Engineering, Universiti Malaysia Perlis, (UniMAP), 02600 Jalan Kangar-Arau, Perlis, Malaysia 2 School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi Selangor, Malaysia a dewisuriyani@unimap.edu.my, b haizaharoon@unimap.edu.my, c ibatal@ukm.my, d ard@ukm.my, e azmi@ukm.my Keywords: Cu 2 O, thin films, ITO, sol-gel, microstructures Abstract Cuprous oxide (Cu 2 O) thin films were formed onto three different substrates such as indium tin oxide (ITO) coated glass, titanium oxide (TiO 2 ) and n-Si substrates by sol-gel spin coating technique. It was found that the formation mechanism of Cu 2 O films onto different substrates lead to different microstructures. The films were characterized by field-emission scanning electron microscopy (FESEM). Based on the FESEM micrographs the grain shape of film prepared were different on ITO, TiO 2 and n-Si substrate with 114 nm, 154 nm and 84 nm respectively. The results indicate that the choice of substrate strongly affect the film morphology, structural and optical properties. Introduction Cuprous oxide (Cu 2 O) is an interesting p-type semiconductor with a direct energy band gap of 2.0 eV. Cu 2 O forms a cubic structure with a lattice parameter of 4.27 Å [1]. With these remarkable optical properties, Cu 2 O has emerged as a promising material in solar energy applications. Furthermore, it is relatively inexpensive to produce and nontoxic with its component elements is readily available [2]. Cu 2 O is a basic compound forming superconducting materials. It is also known that Cu 2 O related materials such as CuAlO 2 and SrCu 2 O 2 families are transparent conductive oxides (TCO) exhibiting p-type conductivity. And these TCOs have electronic structure similar to Cu 2 O, except for considerably larger energy gaps [3]. Due to its promising properties, various method of synthesize of Cu 2 O has been reported such as sputtering, electrodeposition, thermal oxidation, vacuum evaporation, and sol-gel process [1, 2, 4, 5, 6]. Among these, sol-gel is the simplest and convenient technique. The advantages of this technique compare to other technique are low processing temperature, controllable film thickness and morphology [6]. In order to explore the potential of using Cu 2 O for various optoelectronic device applications, it is interesting to deposit Cu 2 O films onto different substrates. Examples are (a) Cu 2 O deposited on the conventional semiconductor Si may be used in electronic devices and (b) Cu 2 O grown on ITO can be used in solar energy cells. Sol-gel using spin coater of Cu 2 O on Si has been rarely reported, only recently Armelao et al reported the sol-gel using dip coater of Cu 2 O on Herasil silica [6]. In this paper we report the success of using the sol-gel spin coater technique to form Cu 2 O films on different substrates and conduct a detailed structural and optical investigation of Cu 2 O films. Experimental The starting compound used in this study was copper (II) acetate in isopropyl alcohol and diethanolamine (DEA, C 4 H 11 NO 2 ) solution and mixed continuously. The details preparation of cuprous oxide thin film was reported elsewhere [7, 8]. The cuprous oxide thin films were deposited Advanced Materials Research Vol. 626 (2013) pp 849-852 © (2013) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMR.626.849 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, www.ttp.net. (ID: 115.132.197.243-17/11/12,05:02:16)