牧 王;G. Wildburg;J. H. Van Esch;P. Bennema;R. J.M. Nolte;H. Ringsdorf

Physical Review Letters

1994

A surface-tension-gradient-induced growth phenomenon is reported in lipid monolayer films. The surface tension gradient is introduced to the monolayer film by local, subtle heating using the microscope light. This surface tension gradient is responsible for compressing the illuminated area continuously and induces the growth of domains of liquid condensed phase. The evolution of morphology from fractal to faceted and then to dendritic patterns is investigated by in situ observations. The mechanism of pattern formation in this system is discussed.

牧 王;G. Wildburg;J. H. Van Esch;P. Bennema;R. J.M. Nolte;H. Rinsdorf

Physical Review Letters

1993

Nucleation is an important step in crystallization, and many self-organized patterns are determined in this process. In this study, after briefly reviewing the fundamentals of nucleation theory, we take a few examples to show the significance of concave-corner-mediated nucleation in both self-organized formation of long-range-ordered patterns and in self-assembly of metallic nano wire array. We show that successive concave-corner-mediated nucleation on the growth front is an important mechanism leading to many long-range ordering effects in crystallization. This mechanism can also be applied in fabricating metallic nano wires with specific geometry, including straight metallic wire array with tunable line width and nanowires with periodic structures.

Fei Jia;Di Zhao;牧 王

Progress in Crystal Growth and Characterization of Materials

2016-6-1

Light intensity distribution in laser interference crystallization with an imperfect phase-shift grating was calculated and compared with that by a perfect one. The effect of zero-order diffracted light on laser interference crystallization was analyzed in detail. The AFM images of a-Si:H film irradiated by a KrF excimer pulsed laser have confirmed the calculated results. Longitudinal periodicity of light intensity distribution was discussed and compared with the Talbot Effect.

Ming Jiang;Mingxiang Wang;牧 王;Kunji Chen

Chinese Journal of Lasers B (English Edition)

1999-1-1

Morphological instability has been studied experimentally in the growth from dilute Ba(NO₃)₂aqueous solution of crystal films with free surfaces. The observation of transitions from faceted crystal to dendrite, and then to fractal-like patterns is presented. The micro-morphologies of these patterns are investigated. It is suggested that the competition between the step movement and the solute transfer in the growth of thin films determines the stability of the faceted crystal comers. The fractal-like pattern is attributed to random successive nucleation, which is induced by the decrease of the nucleation barrier at high supersaturation and the disturbance caused by the competition between surface-tension-gradient and wetting effects.

牧 王;Ru Wen Peng;Piet Bennema;Nai Ben Ming

Philosophical Magazine A: Physics of Condensed Matter, Structure, Defects and Mechanical Properties

1995-2

Oriented LiNbO₃ thin films have been prepared by pulsed laser deposition on fused silica substrates under a proper low electric field. The as-grown films were characterized by means of X-ray diffraction θ-2θ scans, X-ray photo-electron spectrometry and atomic force microscopy. Significant effects of the substrate temperature and magnitude of the applied electric field on the orientation of the films are revealed, demonstrating the preferred electric field of ∼7 V/cm and substrate temperature of 600°C. Drastic influence of the substrate temperature on the stoichiometry of the thin films is also shown. The as-prepared thin films show quite good surface quality.

Z. C. Wu;W. S. Hu;J. M. Liu;牧 王;Z. G. Liu

Materials Letters

1998-3

GaN quantum dots have been successful fabricated on sapphire by using metallorganic chemical vapor deposition (MOCVD) by two-step method, including deposition at 500 °C and annealing at 1050 °C. The density and the size of GaN dots are determined by using an atomic force microscope (AFM), and they are controllable by changing the temperature and the duration of the depositing and the annealing. GaN dots are formed only after annealing at high temperature. The phenomenon can be explained like this: the initial layer deposited at 500 °C is a high energy intermediate phase in which the large strain energy can not be relaxed because of the low temperature depositing.

Peng Chen;Bo Shen;牧 王;Yugang Zhou;Lan Zang;Xiaoyong Liu;Zhenchun Huang;Youdou Zheng;Naiben Min;Yin Hang;Zhizhong Chen

Gaojishu Tongxin/High Technology Letters

1998

The morphological instabilities of two-dimensional hexagonal crystals in lipid monolayers are studied. Fluorescence microscopy indicates that beyond a critical size the faceted crystal develops into dendrites with unusual tip growth behavior, which is not consistent with the current theory of dendritic growth. The morphological transitions in relation to the driving force for two-dimensional crystal growth are also studied.

Cheng Sun;牧 王;Jan Van Esch;Gerald Wildburg;Willem J.P. Van Enckevort;Nai Ben Ming;Piet Bennema;Roelands J.M. Nolte

Physics Letters, Section A: General, Atomic and Solid State Physics

1998-1-12

TiO ₂ thin films on GaAs(1 0 0) substrates were prepared at temperature ranging 30-750°C and pressure from 5 × 10 ^-4 Pa base vacuum to 15 Pa O ₂ , by pulsed laser deposition (PLD). The effects of both the oxygen pressure and the substrate temperature on the properties of TiO ₂ films were investigated. TiO ₂ thin films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). Optimum parameters have been identified for the growth of high-quality TiO ₂ films. At 5 Pa of oxygen ambient pressure, rutile TiO ₂ films with high [1 1 0] orientation were formed at substrate temperature of 700°C. At room temperature (30°C) and 5 × 10 ^-4 Pa base vacuum, rutile TiO ₂ films with a preferred [1 1 0] orientation were also obtained on GaAs(1 0 0) substrates by PLD. Surface morphology of the films showed marked dependence on the substrate temperature. The grain size and their surface roughness increased with raising substrate temperature.

Xiaohua Liu;J. Yin;Z. G. Liu;X. B. Yin;G. X. Chen;牧 王

Applied Surface Science

2001-4-2

Lamellar copper nanowires with a high density of traverse twins (twin spacing even less than one nm) are synthesized (see image). These wires spontaneously grow from a pure electrolyte of CuSO4 by electrodeposition. Micromechanical testing and electrical four-probe measurements impressively demonstrate that the highly twinned nanowires show a remarkably high mechanical strength while at the same time maintaining a high electrical conductivity.

Sheng Zhong;Thomas Koch;牧 王;Torsten Scherer;Stefan Walheim;Horst Hahn;Thomas Schimmel

Small

2009-10-16