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Layer-by-layer pattern propagtion and pulsed laser deposition  [PDF]
F. Westerhoff,L. Brendel,D. E. Wolf
Physics , 2001,
Abstract: In this article kinetic Monte Carlo simulations for molecular beam epitaxy (MBE) and pulsed laser depositon (PLD) are compared. It will be shown that an optimal pattern conservation during MBE is achieved for a specific ratio of diffusion to deposition rate. Further on pulsed laser deposition is presented as an alternative way to control layer by layer growth. First results concerning the island density in the submonolayer regime are shown.
Layer-by-layer growth for pulsed laser deposition  [PDF]
B. Hinnemann,F. Westerhoff,D. E. Wolf
Physics , 2001,
Abstract: Pulsed laser deposition (PLD) is a popular growth method, which has been successfully used for fabricating thin films. Compared to continuous deposition (like molecular beam epitaxy) the pulse intensity can be used as an additional parameter for tuning the growth behavior, so that under certain circumstances PLD improves layer-by-layer growth. We present kinetic Monte-Carlo simulations for PLD in the submonolayer regime and give a description of the island distance versus intensity. Furthermore we discuss a theory for second layer nucleation and the impact of Ehrlich-Schwoebel barriers on the growth behavior. We find an exact analytical expression for the probability of second layer nucleation during one pulse for high Ehrlich-Schwoebel barriers.
Effect of Incident Intensity on Films Growth in Pulsed Laser Deposition
GUAN Li,ZHANG Duan-Ming,LI Zhi-Hua,TAN Xin-Yu,LI Li,LIU Dan,FANG Ran-Ran,LIU Gao-Bin,HU De-Zhi,
关丽
,张端明,李智华,谭新玉,李莉,刘丹,房然然,刘高斌,胡德志

中国物理快报 , 2006,
Abstract: Incident intensity, defined by the amount of particles deposited per pulse, is an important parameter in the film growth process of pulsed laser deposition (PLD). Different from previous models, we investigate the irreversible and reversible growth processes by using a kinetic Monte Carlo method and find that island density and film morphology strongly depend on pulse intensity. At higher pulse intensities, lots of adatoms instantaneously diffuse on the substrate surface, and then nucleation easily occurs between the moving adatoms resulting in more smaller-size islands. In contrast, at the lower pulse intensities, nucleation event occurs preferentially between the single adatom and existing islands rather than forming new islands, and therefore the average island size becomes larger in this case. Additionally, our results show that substrate temperature plays an important role in film growth. In particular, it can determine the films shape and weaken the effect of pulse intensity on film growth at the lower temperatures by controlling the mobility rate of atoms. Our results can match the related theoretical and experimental results.
Unusual scaling for pulsed laser deposition  [PDF]
Berit Hinnemann,Haye Hinrichsen,Dietrich E. Wolf
Physics , 2001, DOI: 10.1103/PhysRevLett.87.135701
Abstract: We demonstrate that a simple model for pulsed laser deposition exhibits an unusual type of scaling behavior for the island density in the submonolayer regime. This quantity is studied as function of pulse intensity and deposition time. We find a data collapse for the ratios of the logarithms of these quantities, whereas conventional scaling as observed in molecular beam epitaxy involves ratios of powers.
Rate Equations and Scaling in Pulsed Laser Deposition  [PDF]
A. C. Barato,H. Hinrichsen,D. E. Wolf
Physics , 2008, DOI: 10.1103/PhysRevE.77.041607
Abstract: We study a simplified model for pulsed laser deposition [Phys. Rev. Lett. {\bf 87}, 135701 (2001)] by rate equations. We consider a set of equations, where islands are assumed to be point-like, as well as an improved one that takes the size of the islands into account. The first set of equations is solved exactly but its predictive power is restricted to a few pulses. The improved set of equations is integrated numerically, is in excellent agreement with simulations, and fully accounts for the crossover from continuous to pulsed deposition. Moreover, we analyze the scaling of the nucleation density and show numerical results indicating that a previously observed logarithmic scaling does not apply.
Growth of Gallium Oxide Nanowires by Pulsed Laser Deposition  [PDF]
Hiroyasu Yamahara, Munetoshi Seki, Hitoshi Tabata
Journal of Crystallization Process and Technology (JCPT) , 2012, DOI: 10.4236/jcpt.2012.24017
Abstract: We report on the synthesis of gallium oxide nanowires by pulsed laser deposition using a gold catalyst. In the vapor-liquid-solid process, gold thickness was the crucial parameter for deciding the morphology of nanowires. In the case of 1 nm thick gold, homogeneous nanowire growth was confirmed at temperatures of 700°C to 850°C. Transmission electron microscopy and selected area electron diffraction measurements showed that the nanowires were polycrystalline. In the cathode luminescence spectra, UV, blue, green and red emission peaks were observed, as reported in previous studies. As growth temperature was increased, the relative intensities of blue, green, and red emissions decreased. Thermal annealing treatments were effective in decreasing the blue, green and red emission peaks, suggesting that these emission peaks were associated with oxygen vacancies.
Monte Carlo simulation of metal deposition on foreign substrates  [PDF]
M. Cecilia Gimenez,Antonio J. Ramirez-Pastor,Ezequiel P. M. Leiva
Physics , 2008, DOI: 10.1016/j.susc.2006.07.050
Abstract: The deposition of a metal on a foreign substrate is studied by means of grand canonical Monte Carlo simulations and a lattice-gas model with pair potential interactions between nearest neighbors. The influence of temperature and surface defects on adsorption isotherms and differential heat of adsorption is considered. The general trends can be explained in terms of the relative interactions between adsorbate atoms and substrate atoms. The systems Ag/Au(100), Ag/Pt(100), Au/Ag(100) and Pt/Ag(100) are analyzed as examples.
Pulsed Laser Deposition of BaTiO3 Thin Films on Different Substrates
Yaodong Yang,Zhiguang Wang,Jie-Fang Li,D. Viehland
Journal of Nanomaterials , 2010, DOI: 10.1155/2010/756319
Abstract: We have studied the deposition of BaTiO3 (BTO) thin films on various substrates. Three representative substrates were selected from different types of material systems: (i) SrTiO3 single crystals as a typical oxide, (ii) Si wafers as a semiconductor, and (iii) Ni foils as a magnetostrictive metal. We have compared the ferroelectric properties of BTO thin films obtained by pulsed laser deposition on these diverse substrates.
Cobalt nitride films produced by reactive pulsed laser deposition
De La Cruz, W.;Contreras, O.;Soto, G.;Pérez-Tijerina, E.;
Revista mexicana de física , 2006,
Abstract: the nitrides of magnetic metal are becoming important due to their potential technological applications. in this work cobalt nitride thin films are deposited by reactive pulsed laser deposition (nitrogen environments) on silicon substrates at room temperature. the resultant films are characterized in-situ by auger, x-ray photoelectron and electron energy loss spectroscopies. the chemical bond of the conx is strongly linked to the stoichiometry, and it can be controlled by the n background pressure. we conclude that this deposition method offers a means for fine-tuning the properties of cobalt nitride.
Superconducting MgB2 thin films by pulsed laser deposition  [PDF]
S. R. Shinde,S. B. Ogale,R. L. Greene,T. Venkatesan,P. C. Canfield,S. L. Budko,G. Lapertot,C. Petrovic
Physics , 2001, DOI: 10.1063/1.1385186
Abstract: Growth of MgB2 thin films by pulsed laser deposition is examined under ex situ and in situ processing conditions. For the ex situ process, Boron films grown by PLD were annealed at 900 C with excess Mg. For the in situ process, different approaches involving ablation from a stoichiometric target under different growth conditions, as well as multilayer deposition involving interposed Mg layers were examined and analyzed. Magnetic measurements on ex situ processed films show TC of ~39 K, while the current best in situ films show a susceptibility transition at ~ 22 K.
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