| Pulsed Laser Deposition (PLD) technique is a versatile technique to prepare many kinds of functional materials. The whole process can be devided into three stages: laser ablation, plasma expansion and film growth. There are so many complex phenomenons in the process of films prepared by PLD technique, so people have carried out the research in this field. Recently, a more integrated Zhang-Li (Z-L) model has been proposed to simulate the interaction between laser and the target, the plasma shock wave expanding, and the deposition process.In this paper,by finite difference method, the evolvement of plasma generated by a pulsed laser is studied for pulsed laser deposition of KTa0.65Nb0.35O3(KTN) thin film. We have discussed the physics mechanism in expansion of the plasma has been explained. At the same time, we have simulated the change of figure of plasma at the different time. The nature of plasma anisotropy expanding is the different original condition in parallel and in perpendicular to target surface direction.Secondly, we summarized the two natural characteristics of PLD film growth: energetic deposition and pulsed deposition. According to the physical mechanism of PLD growth, we have eatablished a Pulsed Kinetic Monte Carlo (PKMC) model to perform the early growth stage of thin film prepared by pulsed laser deposition. The results show that:(a) Substrate temperature as an important fator can demtermine film growth pattern. With the increasing substrate temperature, surface atoms'thermal vibration is accelerated and then the migration rate of adatoms is elevated also. The film morphology can accomplish a factal-dentritic-compact transformation with the increasing substrate temperature.(b) The interaction between energetic particle and adatoms on substrate surface is complex, and we disclosed that there are two main effects in energetic deposition: collision effect, which can leads to more nucleation density; the elevation of surface diffusion of adatoms, which is helpful for adatoms to overcome the Ehrilich-Schwoebel (ES) energy barrier, and jump onto the first layer. All of the two effects can improve layer-by-layer growth. We investigate the different influences of lower energy (<10eV) and higher energy (102~103eV) on island aggregation. The results illustrate that when particle's average kinetic energy is lower, the collision effect is more obvious. In the case of higher energy, the second effect plays a more important role in growth process.(c) Pulse intensity can determine the instantaneous deposition rate, that is to say, the larger pulse intensity will result in more adatoms on surface at the same time, so more nucleatin events will occur and a smoother film can be obtained finally. Considering the kinetic effect, we found that a general scaling form ? | logM (I,θ)|=|logI|α/G' [|logθ|/|logI|β](α=β=1/3) exixts in PLD film growth at the different pulse intensities.(d) Island density and films morphology depend on pulse repetition rate also. At the lower pulse repetition rates, the islands are given more time to ripen due to the longer pulse interval, thus island density is smaller and island aggregation is in compact mode. The island density increases with pulse frequency and the film tends to dispersed and dendritic shape. Especially, we firstly find that island density N ( f ,θ) also can be defined as pulse frequency f and the coverageθ. A new scaling behavior of thin film growth with varying pulse repetition rate exists during film growth, and the scaling form is written as ? log( M ( f ,θ)) = log( f )αG[ log(θ) / log( f)β], where the exponentsα=β= ? 1/ 4.
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