INVESTIGATION OF THE EFFECT OF OXYGEN AND SUBSTRATE BIAS ON THE DEFECT STRUCTURE OF SPUTTER-DEPOSITED SnO X FILMS

Abstract

In recent years the research interest in SnO{sub x} thin films has been renewed due to their industrial applications. Specific uses have been found in liquid crystal displays, as heated windscreens for car, as a means of ensuring the mechanical reaction stability of glass bottles, as transparent heat reflectors in sodium or incandescent lamps and as high quality optical elements. Especially SnO{sub 2} films are of great technological interest as transparent electrodes and as heat-reflecting filters, because SnO{sub 2} has a high energy gap (3.6 eV) and it can possess high carrier concentrations. The purpose of the present study is to investigate the effect of oxygen and substrate bias on the defect structure of sputter deposited SnO{sub x} films. The investigation was carried out using transmission electron microscopy (TEM), transmission electron diffraction (TED), X-ray diffraction and positron annihilation spectroscopy (PAS). The reason for using PAS is that it responds to the presence of point defects. Several studies have suggested that dislocations and vacancies play a major role in determining the properties of thin films.