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Ni induced few-layer graphene growth at low temperature by pulsed laser deposition
K. Wang,G. Tai,K. H. Wong,S. P. Lau
AIP Advances , 2011, DOI: 10.1063/1.3602855
Abstract: We have used pulsed laser deposition to fabricate graphene on catalytic nickel thin film at reduced temperature of 650 °C. Non-destructive micro-Raman spectroscopic study on our samples, measuring 1x1 cm2 each, has revealed few-layer graphene formation. Bi-, tri-, and few-layer graphene growth has been verified by High Resolution Transmission Electron Microscopy. Our experimental results imply that the number of graphene layers formation relies on film thickness ratios of C to Ni, which can be well controlled by varying the laser ablation time. This simple and low temperature synthesizing method is excellent for graphene based nanotechnology research and device fabrication.
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.
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.
Growth mechanisms of ceria- and zirconia-based epitaxial thin films and hetero-structures grown by pulsed laser deposition
Daniele Pergolesi,Marco Fronzi,Emiliana Fabbri,Antonello Tebano,Enrico Traversa
Materials for Renewable and Sustainable Energy , 2013, DOI: 10.1007/s40243-012-0006-6
Abstract: Thin films and epitaxial hetero-structures of doped and undoped CeO2, and 8 mol% Y2O3 stabilized ZrO2 (YSZ), were fabricated by pulsed laser deposition on different single crystal substrates. Reflection high energy electron diffraction was used to monitor in situ the growth mechanism of the films. Two distinct growth mechanisms were identified along the (001) growth direction for the Ce- and Zr-based materials, respectively. While the doped or undoped ceria films showed a 3-dimensional growth mechanism typically characterized by a pronounced surface roughness, YSZ films showed an almost ideal layer-by-layer 2-dimensional growth. Moreover, when the two materials were stacked together in epitaxial hetero-structures, the two different growth mechanisms were preserved. As a result, a 2-dimensional reconstruction of the ceria-based layers determined by the YSZ film growing above was observed. The experimental results are explained in terms of the thermodynamic stability of the low-index surfaces of the two materials using computational analysis performed by density functional theory.
Initial stages of nickel oxide growth on Ag(001) by pulsed laser deposition  [PDF]
S. H. Phark,Y. J. Chang,T. W. Noh,J. -S. Kim
Physics , 2009, DOI: 10.1103/PhysRevB.80.035426
Abstract: Submonolayers of nickel oxide films were grown on an Ag(001) by pulsed laser deposition, and characterized in-situ by both scanning tunneling microscopy and X-ray photoelectron spectroscopy. We observed quasi-two-dimensional growth of the film, and clearly identified several kinds of defects, such as embedded metallic Ni clusters and, notably, oxygen atoms, even while looking deeply into the substrate. These originated from Ni and O hyperthermal projectiles as well as from NiO clusters that were formed during laser ablation of a NiO target. Those defects played a role of nucleation sites in extending the nucleation stage of thin film growth.
Electrochemical Response of Platinum Ultrathin Layer Formed by Pulsed Laser Deposition  [PDF]
Takeshi Ito,Satoru Kaneko,Masayuki Kunimatsu,Yasuo Hirabayashi,Masayasu Soga,Koji Suzuki
International Journal of Electrochemistry , 2011, DOI: 10.4061/2011/463281
Abstract: Ultrathin layer of platinum (ULPt) was deposited on glassy carbon (GC) substrate by using pulsed laser deposition (PLD) method, and electrochemical properties of the ULPt were discussed. The deposition was simply performed at room temperature with short deposition time. Atomic force microscopy and scanning electron microscopy images showed the flat surface of the ULPt. X-ray photoelectron spectroscopy (XPS) characterized the ULPt in the Pt(0) state, and biding energy of ULPt was positively shifted. These results indicated that nanostructure of Pt thin layer was formed. The electrochemical activity of the prepared ULPt on GC substrate was superior to a bulk Pt electrode regarding the potential and the magnitude of current on oxidizing hydrogen peroxide. This fast and easily prepared low-cost electrode had the potential to replace a conventional bulk metal electrode. 1. Introduction Recently, high sensitivity of palm-size biosensors is required for home medical care and point of care testing (POCT). Electrochemical detection provides to downsize a package of the sensor; however, it needs to improve the sensitivity of an electrode. Platinum (Pt) is widely used as the electrochemical material since Pt is a corrosion-inhibiting material with electrochemical stability. One of the biosensing applications is a detector for oxidation of hydrogen peroxide, which is generated by enzymatic reaction on oxidase-based biosensors. Many studies have been reported about the performance of Pt-based electrodes and their fabrication method for biosensing. In particular, Pt nanoparticle has great potential to improve the sensitivity and decrease the electrochemical potential on detecting hydrogen peroxide. The electrode requires the surface flatness to decrease the noise level, and highly dispersed Pt nano-particles increase active area. To meet these requirements, Pt nano-particles dispersed carbon electrode is one of the candidates. Electrochemical deposition can prepare Pt-black electrode at low cost as a simple method [1–4]. However, it is difficult to control the particle size and dispersion. The Pt-black electrode has high electrochemical activity with much large surface area compared to Pt bulk electrode. Since this large surface area may cause a high background current, it also provides low detection limit. Some groups reported that nanoscale Pt clusters were obtained using thermolysis of a carbon precursor with Pt particles by a chemical vapor deposition (CVD) method [5–7]. This process needs polymer synthesis skills and high temperature of 600°C for thermolysis.
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.
Growth and Structural Properties of Indium doped SrTiO3 Films by Pulsed Laser Deposition
脉冲激光沉积法生长In掺杂SrTiO3薄膜及其微观结构研究

ZHANG Yi-Wen,LI Xiao-Min,ZHAO Jun-Liang,YU Wei-Dong,GAO Xiang-Dong,WU Feng,
张亦文
,李效民,赵俊亮,于伟东,高相东,吴 峰

无机材料学报 , 2008,
Abstract: Undoped and In-doped SrTiO3(STO) films were grown on MgO/TiN/Si(100) substrates by pulsed laser deposition(PLD). The growth mechanism, crystallinity, surface morphology, and UV-Raman spectra of the films were studied. Results indicate that undoped STO films show high quality crystalline structure with highly (200) orientation. With Indium doping, the crystallinity of the STO film deteriorate, the first order Raman peaks increase indicating the breaking of crystal symmetry, and the film growth mode change from the layer-by-layer mode to island-layer mixed one, resulting in the roughening of the film surface. Furthermore, the crystallinity and (200) orientation of In-doped STO film can be enhanced significantly by introducing an undoped STO buffer layer.
Sims Characterisation of ZnO Layer Prepared By Pulsed Laser Deposition  [cached]
Andrej Vincze,Miroslav Michalka,Jaroslav Bruncko,Frantisek Uherek
Advances in Electrical and Electronic Engineering , 2005,
Abstract: New material development requires new technologies to create and prepare basic material for semiconductor industry and device applications. Materials have given properties, which exhibit particulary small tolerances. One of the most important and promising material is recently ZnO. ZnO has specific properties for near UV emission and absorption optical devices. The pulsed laser deposition (PLD) is one of the methods to prepare this type of material. The aim of this paper is to compare properties of ZnO layers deposited from pure Zn target in oxygen atmosphere and the analysis of their surface properties by secondary ion mass spectroscopy (SIMS), atomic force microscopy (AFM) and scanning electron microscopy (SEM).
Growth of nanolaminate structure of tetragonal zirconia by pulsed laser deposition
Govindasamy Balakrishnan,, Parasuraman Kuppusami, Dillibabu Sastikumar and Jung Il Song
Nanoscale Research Letters , 2013, DOI: 10.1186/1556-276X-8-82
Abstract: Alumina/zirconia (Al2O3/ZrO2) multilayer thin films were deposited on Si (100) substrates at an optimized oxygen partial pressure of 3 Pa at room temperature by pulsed laser deposition. The Al2O3/ZrO2 multilayers of 10:10, 5:10, 5:5, and 4:4 nm with 40 bilayers were deposited alternately in order to stabilize a high-temperature phase of zirconia at room temperature. All these films were characterized by X-ray diffraction (XRD), cross-sectional transmission electron microscopy (XTEM), and atomic force microscopy. The XRD studies of all the multilayer films showed only a tetragonal structure of zirconia and amorphous alumina. The high-temperature XRD studies of a typical 5:5-nm film indicated the formation of tetragonal zirconia at room temperature and high thermal stability. It was found that the critical layer thickness of zirconia is ≤10 nm, below which tetragonal zirconia is formed at room temperature. The XTEM studies on the as-deposited (Al2O3/ZrO2) 5:10-nm multilayer film showed distinct formation of multilayers with sharp interface and consists of mainly tetragonal phase and amorphous alumina, whereas the annealed film (5:10 nm) showed the inter-diffusion of layers at the interface.
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