Random Surface Morphology Of Zno Optical Thin Film Analysis And Light Scattering Characteristics Of Study

Film surface morphology, film growth mechanism, the absorption, reflection, and many other surface phenomena are closely related, while the surface random roughness is also directly related to the film's mechanical, electrical, optical and other aspects of the nature and function. Therefore, the research of the roughening mechanism and character on the film surface is an important subject in the area of film study and makes very important sense on both theoretical and application sides.In this thesis, by using the electron beam evaporation method assisted with ion source, we have prepared several ZnO films with Si as substrate and SiO2 as buffer layer. These films were treated via thermal insulation process and further annealed under five different temperatures (400℃-800℃). In order to make an in-depth analysis of the growth mechanism and film surface features, we have measured these sample films by AFM and analyzed their surface roughness, grain size, and fractal dimension, as well as the relation between the thin film's parameters and the annealing temperature. We have also set up a thin film scattering test system to study the influence of wavelength, polarization, and incident angle of the incident light on the reflected power and polarization properties of the films. Experiments and data analysis show that:(1) Thin films have obvious fractal features:Fractal dimension D is convinient to describe the surface characteristics of thin films. Overall, there is inversely proportional relationship between the fractal dimension and surface quality of thin film.(2) There exists a certain relationship between fractal dimension D and the annealing temperature T:With the increase of T, the surface quality will become better, and D will decreases gradually; when the annealing temperature T reaches a certain value, the surface quality will deteriorate, which induces an increasement value of D.(3) The films show different reflected power and polarization properties for different wavelength, polarization, and incident angle of incident light.The researches of film surface properties and roughening mechanism in this paper is helpful to understanding of thin film's growth mechanism and improving the farication technique of films, which shows a certain value for enhancing the quality of films. The applied research of fractal theory and optical polarization study of ZnO thin films can provide both theoretical and engineering references for researchers in this area.