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arXiv · 0909.1716

Understanding the Clean Interface between Covalent Si and Ionic Al2O3

H. J. Xiang·Juarez L. F. Da Silva·Howard M. Branz·Su-Huai Wei
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Abstract

The atomic and electronic structures of the (001)-Si/(001)-gamma-Al2O3 heterointerface are investigated by first principles total energy calculations combined with a newly developed "modified basin-hopping" method. It is found that all interface Si atoms are fourfold coordinated due to the formation of Si-O and unexpected covalent Si-Al bonds in the new abrupt interface model. And the interface has perfect electronic properties in that the unpassivated interface has a large LDA band gap and no gap levels. These results show that it is possible to have clean semiconductor-oxide interfaces.

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H. J. Xiang, Juarez L. F. Da Silva, Howard M. Branz, Su-Huai Wei. 2009-09-09. Understanding the Clean Interface between Covalent Si and Ionic Al2O3. https://doi.org/10.1103/physrevlett.103.116101

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