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Title: Nucleation-mediated lateral growth on foreign substrate

Abstract

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.

Authors:
 [1];  [2];  [3];  [3];  [1];  [1];  [1]
  1. unknown
  2. Chinese Academy of Sciences
  3. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931904
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry C; Journal Volume: 111; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NUCLEATION; ORIENTATION; SUBSTRATES; CRYSTAL GROWTH; MATHEMATICAL MODELS; ORDER PARAMETERS

Citation Formats

Shu, Da-Jun, Wang, Mu, Liu, Feng, Zhang, Zhenyu, Peng, Ru-Wen, Zhang, Rong, and Ming, Nai-Ben. Nucleation-mediated lateral growth on foreign substrate. United States: N. p., 2007. Web. doi:10.1021/jp0649908.
Shu, Da-Jun, Wang, Mu, Liu, Feng, Zhang, Zhenyu, Peng, Ru-Wen, Zhang, Rong, & Ming, Nai-Ben. Nucleation-mediated lateral growth on foreign substrate. United States. doi:10.1021/jp0649908.
Shu, Da-Jun, Wang, Mu, Liu, Feng, Zhang, Zhenyu, Peng, Ru-Wen, Zhang, Rong, and Ming, Nai-Ben. Mon . "Nucleation-mediated lateral growth on foreign substrate". United States. doi:10.1021/jp0649908.
@article{osti_931904,
title = {Nucleation-mediated lateral growth on foreign substrate},
author = {Shu, Da-Jun and Wang, Mu and Liu, Feng and Zhang, Zhenyu and Peng, Ru-Wen and Zhang, Rong and Ming, Nai-Ben},
abstractNote = {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.},
doi = {10.1021/jp0649908},
journal = {Journal of Physical Chemistry C},
number = 3,
volume = 111,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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