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arXiv · 1501.03934

Nucleation and Growth Mechanism of a Covalent Material: Magic Clusters and Chemical Reactions

Yi-Hsien Lee·Kuntal Chatterjee·Chung-Kai Fang·Shih-Hsin Chang·I-Po Hong·Tien-Chih Chang·Ing-Shouh Hwang
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Abstract

With scanning tunneling microscopy, we study the very early stage of Si deposition on a Pb monolayer covered Si(111) surface. We find a special type of Si magic clusters which are highly mobile on the defect-free surface but may be trapped temporarily at certain boundary or defect sites. They may also aggregate and a special aggregate arrangement is found to be stable for one to two days at room temperature. Adding more Si on the cluster aggregate can transform it into a metastable structure. A scenario based on magic clusters and their chemical reactions is proposed to describe the nucleation and growth processes of covalent materials.

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Yi-Hsien Lee, Kuntal Chatterjee, Chung-Kai Fang, Shih-Hsin Chang, I-Po Hong, Tien-Chih Chang, Ing-Shouh Hwang. 2015-01-16. Nucleation and Growth Mechanism of a Covalent Material: Magic Clusters and Chemical Reactions. https://arxiv.org/abs/1501.03934

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