Optical And Electrical Properties Of Ta Doped Titanium Oxide Films

In this paper, Tantalum-doped TiO₂transparent conductive films were successfully deposited onglass substrates at300℃by pulsed laser depositionwith a wavelength of248nm and frequency of5Hz for the KrF laser source. After post-annealing in vacuum （10-4Pa）, these films were crystallizedinto an anatase TiO₂structure. Experiments indicated that appropriate amount of Ta dopants （4mol.%Ta）decreased resistivity of n-type Tantalum-doped TiO₂semiconductor films. By controlling theenergy density of pulsed laser, oxygen partial pressure, substrate temperatures and post-annealingtemperatures （450℃⁶50℃）, we got transparent conductive Ta doped titanium oxide films withgood optical and electrical properties. The resistivity of the films was measured as around8.710-4·cm with a carrier concentration as4.7×1021cm3and mobility as1.19cm2v-1s-1. Such films exhibitedhigh transparency of over80%in the visible light region. The results indicated that tantalum-dopedanatase TiO₂films have a great potential as transparent conducting oxides.This thesis includes five chapters:Chapter1introduces the basic knowledge of semiconductor physics, physical properties of TiO₂and its preparation method as well the current research.In chapter2, we present the preparation method of Ta-doped TiO₂targets and thin films.Experimental methods involved in this thesis are also introduced in this chapter.In chapter3, it has been shown the study of structures, optical properties and electricalconductivity of Tantalum-doped TiO₂thin films as a function of post-annealing conditions.Chapter4investigates the deposition and surface morphology of Tantalum-doped TiO₂films onPS balls.A summary of our research and proposes for further investigation are given in the last chapter.