The Experts below are selected from a list of 3177 Experts worldwide ranked by ideXlab platform
Nai Ben Ming - One of the best experts on this subject based on the ideXlab platform.
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nucleation mediated lateral growth of crystalline islands on Foreign Substrate an origin of long range ordering in pattern formation
2007Co-Authors: Mu Wang, Da-jun Shu, Ru-wen Peng, Nai Ben MingAbstract:Heteroepitaxial thin film growth may start by nucleating three‐dimensional (3D) or two‐dimensional (2D) islands on Foreign Substrate. Depending on the interfacial energies, heteroepitaxial growth can be categorized into three modes: Frank‐van der Merwe (FM), Stranski‐Krastanow (SK), and Volmer‐Weber (VW). In this lecture, we concentrate on the detail process of horizontal extension of a crystalline island on Foreign Substrate via successive nucleation at the concave corner of the crystal facet and the Foreign Substrate. It is demonstrated that due to the difference of surface tensions at the concave corner, once a nucleus appears at the corner, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally, with its crystallographic orientation continuously rotated. Such a previously untouched effect could be the physical origin to form a few regular spatial patterns in the interfacial growth. A theory is developed, which provides a criterion to observe such an effect in the nucleation‐mediated lateral growth.
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Nucleation-mediated lateral growth on Foreign Substrate
2006Co-Authors: Da-jun Shu, Mu Wang, Feng Liu, Zhenyu Zhang, Ru-wen Peng, Rong Zhang, Nai Ben MingAbstract:A model is developed to deal with lateral growth of a crystalline layer on a Foreign Substrate, which is mediated by successive nucleation at the concave corner defined by the meeting of a crystal facet and the Substrate. It is demonstrated that due to an imbalance of surface/interface tensions at the concave corner, once the embryo of a nucleus is formed, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally on the Substrate, with its crystallographic orientation continuously rotated. In this way, a regular spatial pattern with well-defined long-range order is eventually achieved. Our model provides a criterion to predict when such an effect becomes observable in the nucleation-mediated lateral growth. The theoretical expectations are consistent with the experimental observations.
Alexander Milchev - One of the best experts on this subject based on the ideXlab platform.
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On the role of surface active agents in the nucleation step of metal electrodeposition on a Foreign Substrate
1994Co-Authors: E. Michailova, M. Peykova, D. Stoychev, Alexander MilchevAbstract:Abstract The effect of surface active agents on the thermodynamics and kinetics of electrochemical nucleation has been analysed on the basis of the classical and atomistic theories of phase formation. The theoretical predictions were compared with experimental results obtained by studying the nucleation kinetics of mercury on platinum in both the absence and the presence of potassium nitrate, which proved to be a surface active agent with respect to the bulk mercury phase. The overpotential dependence of the stationary nucleation rate was measured at different potassium nitrate concentrations. It was shown that surface active agents which change the properties of the new bulk phase may not significantly affect the state of small clusters during the process of nucleus formation.
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electrochemical phase formation on a Foreign Substrate basic theoretical concepts and some experimental results
1991Co-Authors: Alexander MilchevAbstract:Abstract Electrochemical phase formation is a typical example of a first-order phase transition. The precursor of the overall phase change is nucleation—the appearance of small clusters of atoms or molecules carrying the basic properties of the new phase. Why and how the nuclei form on a Foreign Substrate are the fundamental questions addressed by this article.
Da-jun Shu - One of the best experts on this subject based on the ideXlab platform.
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nucleation mediated lateral growth of crystalline islands on Foreign Substrate an origin of long range ordering in pattern formation
2007Co-Authors: Mu Wang, Da-jun Shu, Ru-wen Peng, Nai Ben MingAbstract:Heteroepitaxial thin film growth may start by nucleating three‐dimensional (3D) or two‐dimensional (2D) islands on Foreign Substrate. Depending on the interfacial energies, heteroepitaxial growth can be categorized into three modes: Frank‐van der Merwe (FM), Stranski‐Krastanow (SK), and Volmer‐Weber (VW). In this lecture, we concentrate on the detail process of horizontal extension of a crystalline island on Foreign Substrate via successive nucleation at the concave corner of the crystal facet and the Foreign Substrate. It is demonstrated that due to the difference of surface tensions at the concave corner, once a nucleus appears at the corner, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally, with its crystallographic orientation continuously rotated. Such a previously untouched effect could be the physical origin to form a few regular spatial patterns in the interfacial growth. A theory is developed, which provides a criterion to observe such an effect in the nucleation‐mediated lateral growth.
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Nucleation-mediated lateral growth on Foreign Substrate
2006Co-Authors: Da-jun Shu, Mu Wang, Feng Liu, Zhenyu Zhang, Ru-wen Peng, Rong Zhang, Nai Ben MingAbstract:A model is developed to deal with lateral growth of a crystalline layer on a Foreign Substrate, which is mediated by successive nucleation at the concave corner defined by the meeting of a crystal facet and the Substrate. It is demonstrated that due to an imbalance of surface/interface tensions at the concave corner, once the embryo of a nucleus is formed, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally on the Substrate, with its crystallographic orientation continuously rotated. In this way, a regular spatial pattern with well-defined long-range order is eventually achieved. Our model provides a criterion to predict when such an effect becomes observable in the nucleation-mediated lateral growth. The theoretical expectations are consistent with the experimental observations.
Milos Nesladek - One of the best experts on this subject based on the ideXlab platform.
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transient nucleation on inhomogeneous Foreign Substrate
1998Co-Authors: Z Kožisek, P Demo, Milos NesladekAbstract:Nucleation from the vapor phase on a Foreign Substrate with a low number of inhomogeneities is studied. Kinetic equations describing the 3D nucleation on active sites are solved numerically. It is shown that the cluster flux (i.e., the rate of formation of nuclei of a given size) reaches some extremal value at certain time and then tends to zero as time increases. In such a sense, formation of nuclei is a fully nonstationary process, in contrast to the standard nucleation theory. The total number of nuclei formed on a unit surface reaches for a sufficiently long time some stationary value, which is close to the number of nucleation active sites.
Mu Wang - One of the best experts on this subject based on the ideXlab platform.
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nucleation mediated lateral growth of crystalline islands on Foreign Substrate an origin of long range ordering in pattern formation
2007Co-Authors: Mu Wang, Da-jun Shu, Ru-wen Peng, Nai Ben MingAbstract:Heteroepitaxial thin film growth may start by nucleating three‐dimensional (3D) or two‐dimensional (2D) islands on Foreign Substrate. Depending on the interfacial energies, heteroepitaxial growth can be categorized into three modes: Frank‐van der Merwe (FM), Stranski‐Krastanow (SK), and Volmer‐Weber (VW). In this lecture, we concentrate on the detail process of horizontal extension of a crystalline island on Foreign Substrate via successive nucleation at the concave corner of the crystal facet and the Foreign Substrate. It is demonstrated that due to the difference of surface tensions at the concave corner, once a nucleus appears at the corner, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally, with its crystallographic orientation continuously rotated. Such a previously untouched effect could be the physical origin to form a few regular spatial patterns in the interfacial growth. A theory is developed, which provides a criterion to observe such an effect in the nucleation‐mediated lateral growth.
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Nucleation-mediated lateral growth on Foreign Substrate
2006Co-Authors: Da-jun Shu, Mu Wang, Feng Liu, Zhenyu Zhang, Ru-wen Peng, Rong Zhang, Nai Ben MingAbstract:A model is developed to deal with lateral growth of a crystalline layer on a Foreign Substrate, which is mediated by successive nucleation at the concave corner defined by the meeting of a crystal facet and the Substrate. It is demonstrated that due to an imbalance of surface/interface tensions at the concave corner, once the embryo of a nucleus is formed, the crystallographic orientation of the nucleus is spontaneously twisted. By successive nucleation at the concave corner, the crystalline layer develops laterally on the Substrate, with its crystallographic orientation continuously rotated. In this way, a regular spatial pattern with well-defined long-range order is eventually achieved. Our model provides a criterion to predict when such an effect becomes observable in the nucleation-mediated lateral growth. The theoretical expectations are consistent with the experimental observations.