Nano Zno Doped Composite Thin Films With Optical Properties

The zinc oxide(ZnO),which has a quite big exciton binding energy(60meV),is one kind of direct bandgap(3.37eV)Ⅲ-Ⅵrace compound semiconducting material,and theoretically may realize the ultraviolet ray stimulated emission under the room temperature.At the same time,ZnO is the high quality piezoelectricity,the gas issensitive and the photoelectric material.This paper used sol-gel prepared by Mg-doped ZnO films and the use of electron beam evaporation method.ZnO/TiO₂ composite film,by controlling the substrate temperature,annealing temperature and the main parameters such as doping, the crystal ZnO films LED structure and characteristics of a more systematic study.First,quartz and silicon substrate,after annealing 500℃doped MgZnO film,the concentration of its doping ZnO films on the structure and optical properties of the impact. The results showed that 3%Mg content in ZnO thin film sample c-axis orientation of the best and has a good crystallization of quality,UV-LED with the introduction of Mg blue shift,and the peak strength enhanced,half-width decreases,Mg can be controlled through the incorporation of regulation ZnO films width of the ban,a ban width of 3.37 eV-7.7eV for the film adjustable band gap,can be prepared to meet the requirements of the optoeleetronie devices designed to provide a theoretical basis for the film.Secondly,to single crystal silicon substrate,in different substrate temperature of the ZnO/TiO₂ composite film,a different analysis of temperature on ZnO/TiO₂ composite film of the structure and optical properties of the impact.The results showed that the experiment of ZnO are amorphous,in the 250℃direct growth in TiO₂ buffer layer on the amorphous ZnO films,because the existence of TiO₂ buffer layer made of crystal ZnO films significantly improve quality and achieve a strong purple,Light,strong and weak here the launch of the green.Finally,a single crystal silicon substrate,250℃directly in the growth of ZnO/TiO₂ composite film,of different temperatures on ZnO/TiO₂ composite film of the structure and optical properties of the impact.The results showed that,after annealing the ZnO films are hexagonal wurtzite structure along the perpendicular to the substrate and the C axis of choosing the best growth with annealing temperature rises,because TiO₂ buffer the increased crystallization,ZnO thin film of crystalline quality Also gradually increase, when the annealing temperature was 600℃,the crystallization of the best quality film,and it has launched the strongest and the weakest UV Green fired,and the amorphous ZnO films of high-quality LED,but in 700℃annealing the ZnO films ultraviolet emission efficiency,as ZnO films and TiO₂ buffer between the spread of atomic movement enhance each other,leading to the decline in the quality of crystallization.