Structure and morphology of nanostructured zinc oxide thin films Prepared by dip-vs. spin-coating methods

Abstract

In this study, we use dipping and spinning methods to coat glass slides with sol-gel ZnO thin films, composed of zinc acetate dihydrate, monoethanolamine (MEA), de-ionized water and isopropanol. The effect of the annealing temperature on the structural morphology and optical properties of these films is investigated. These ZnO films were preheated at 275 ºC for 10 min and annealed either at 350, 450 or 550 ºC for 60 min. As-deposited films, formed by amorphous zinc oxide-acetate submicron particles, are transformed into a highly-oriented ZnO after thermal treatment. The surface morphology, phase structure and optical properties of the thin films were investigated by scanning electron microscopy, X-ray diffraction (XRD) and optical transmittance. Both techniques produced nanostructured ZnO thin films with well-defined orientation. The annealed films were transparent in the visible range with an absorption edge at about 375 nm and a transmittance of ca 85-90% with an average diameter of 40 nm. XRD results show the film was composed of polycrystalline wurtzite, with a preferential c-axis orientation of (002) and a single sharp XRD peak at 34.40, corresponding to the hexagonal ZnO. The grain size is increased by the annealing temperature. Both coating techniques create sol-gel ZnO films with the potential for application as transparent electrodes in optic and electronic devices.

Preparation and characterization of ZnO nanocrystallines in the presence of an ionic liquid using microwave irradiation and photocatalytic activity

“…Therefore, searching new methodology to synthesize nano-sized ZnO is of great significance for both fundamental study and practical applications. Various methods such as thermal decomposition, chemical vapor deposition, sol-gel, spray pyrolysis, and precipitation have been developed for the fabrication of nano-sized ZnO [13][14][15][16][17]. However, high temperature or long reaction time was usually involved in these methods.…”

Thin Films for Immobilization of Complexes with Optical Properties

“…Spin coating combined with the sol-gel process offers a simple, low cost, and highly controlled way of film deposition [35]. In recent years, the method has been used for coating in microelectronics [36] and studied for deposition of transparent conducting oxides [37], for ferroelectric thin films [38], for indium oxide thin films [39], for doped and undoped hematite films [40], for ZnO thin films [35,[41][42][43][44], for titanium oxide films [45], for yttria-stabilized zirconia thin films [46], for mesoporous silica thin films on a silicon substrate [47], and so on. phen in MMA [28].…”

Nanocrystalline Cu2O/p-Si solar light-responsive Schottky photodiode

“…Various techniques were employed for the preparation of Cu 2 O thin films such as radio frequency (r-f) sputtering & F. Yakuphanoglu fyhan@hotmail.com [5], electro-deposition (ED) [6], ion-beam sputtering (IBS) [7], thermal oxidation (TO) [8], dip coating (DC) [9], reactive laser ablation (RLA) [10], anodic oxidation (AO) [11], metal-organic chemical vapor deposition (MOCVD) [12], chemical bath deposition (CBD) [13], successive ionic layer adsorption and reaction (SILAR) [14], spray pyrolysis method (SP) [15], and sol-gel spin coating (SGSC) [16]. Among these methods, SGSC is attracted special interest for the synthesis of Cu 2 O thin films.…”