PULSED LASER DEPOSITION OF ZnO-Ti02 NANOCOMPOSITE THIN FILMS AND THEIR HETEROSTRUCTURES

Abstract

The main aim of the present work was to synthesize good quality ZnO, Ti02 and ZnO- Ti02 nanocomposite thin films by Pulsed Laser Deposition (PLD) technique and to investigate the structural, optical and dielectric properties of these thin films. We have also make efforts to improve the crystallinity and photoluminescence properties of ZnO, Ti02 thin film using buffer layer. Chapter 1 gives an overview of Nanostructured thin film and the thin film growth process. The background of selected semiconductor oxides i.e. ZnO and Ti02 are discuss briefly. The chapter includes the discussions on the structural, optical and transport properties of these oxides. An insight of ZnO-TiO2 system has also been presented. Chapter 2 presents the details of experimental techniques, which have been used for the growth and characterization of oxide thin films. This chapter is divided into three sections which deal with synthesis techniques, basic characterization and measurement of optical and dielectric properties. Chapter 3 describes the growth and characterization of ZnO nanocrystalline thin films. This chapter is divided into three sections. The first section mainly describes the effect of substrate on structural and optical properties of ZnO thin film. The second section deals with the effect of Ti02 buffer layer on the properties of ZnO thin film. In last section, the dielectric properties of ZnO bulk and thin film have been studied. Chapter 4 describes the growth and characterization of Ti02 nanocrystalline thin films. The first section of this chapter mainly describes the effect of substrate on structural and optical properties of Ti02 thin film. The second section deals with the effect of ZnO buffer layer on the properties of Ti02 thin film. The dielectric properties of TiO2 bulk and thin films have been studied in third section. Chapter 5 describes the effect of substrate temperature on ZnO-TiO2 nanocomposite thin films. Zinc titanate (ZnTiO3) ceramic target was prepared by conventional solid state reaction method using ZnO and Ti02 in a molar ratio of 1:1. The effect of substrate temperature on the structural, optical and dielectric properties of ZnTiO3 thin film has been studied Chapter 6 presents the summary and conclusion of the entire work presented in the thesis and also proposes the future directions in which these studies can be extended.