| The preparation of the thin film material is determined by growth dynamics of the film interface, which is manifested as a series processes such as adhesion, diffusion and evaporation, and these processes governs the effects of nucleation, growth front and the interactive action between islands. It is significant for the controlling and improving of the preparation techniques to study in atomic level all kinds of complex processes during the growth of the thin film. The growth process of the thin film has been understood preliminarily recurring to the computer technology, and it can be explored with the help of the new experimental observation equipments, such as the atomic force microscope, the scanning a tunneling microscope, the hot atom scattering technique, the low-energy electron diffraction technique and the high-energy electron diffraction technique. In this thesis, based on the theoretic model of the film growth dynamics, the variation of the surface height and the characteristic parameters of surface with the time can be obtained by use of the calculational simulation and the experimental measurement.In chapter 1, a review of the known results of the thin film growth is presented, and the growth stage of the thin film includes the initial nucleation theory, the cluster growth, the coalescence, the percolation of cluster, the factors influencing thin film growth, and so on. The corresponding testing technology of the thin film is also retrospected. Thus, we put forward the idea that the thin film growth mechanism is studied by using thin film surface characteristics, such as the variation of the parameters of the surface.In chapter 2, starting from the theory of the statistics, we study further the morphology of the thin film. The characteristics of the thin film can be described by the first-order statistical properties and the second-order statistical properties of the surface, for examples, the height probability distribution, the auto-correlation function and the height-height correlation function. These statistics properties are relationed to the parameters of the surface. For the fractal surface, the parameters of the surface can be described quantificationally by the lateral correlation length, interface width, the growth exponent and the roughness exponent. Theoretically, the process of the thin growth dynamics can be simulated by the Kuramoto-Sivashinsky model (K-S), the Edwards-Wilkinson model, Kardar-Parisi-Zhang model (KPZ), Mullins diffusion model, etc. Therefore, we expatiate these above contents in this chapter.In chapter 3, on basis of the K-S model for the thin film growth, we programme and simulate calculationally the growth process of the thin film. In the differential operation, we expand the first differential coefficient and the higher differential according to Laglange 5-point and 4-order interpolation method. The calculation results show that the process of the thin film growth and the influence of the parameters of this model on the morphology of the growth film are obvious. From the calculation data, we can also obtain the parameters of the surface of the thin film by the nonlinear fittness.In Chapter 4, we prepare the GaN thin films on Si by using the pulsed laser deposition method, and obtain the pattern of the surface morphology measured by atomic force microscopy. Based on fractal theory, the roughness exponent, the lateral correlation length and the interface width can be extracted through the numerical correlation calculations of the data for the surface morphology. Through the comparation of the results of the measurement and the simulation according to K-S model, we draw the conclusion that the film growth can be described perfectly by the K-S model in short time and by Mullins diffusion equation in long time.In chapter 5, we give a summary of this paper, and put forward the following work plan about the study on the simulational and experimental studies of film growth dynamics.
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