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arXiv · 0904.2474

First-Principles Study for Evidence of Low Interface Defect Density at Ge/GeO$_2$ Interfaces

Shoichiro Saito·Takuji Hosoi·Heiji Watanabe·Tomoya Ono
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Abstract

We present the evidence of the low defect density at Ge/GeO$_2$ interfaces in terms of first-principles total energy calculations. The energy advantages of the atom emission from the Ge/GeO$_2$ interface to release the stress due to the lattice mismatch are compared with those from the Si/SiO$_2$ interface. The energy advantages of the Ge/GeO$_2$ are found to be smaller than those of the Si/SiO$_2$ because of the high flexibility of the bonding networks in GeO$_2$. Thus, the suppression of the Ge-atom emission during the oxidation process leads to the improved electrical properties of the Ge/GeO$_2$ interfaces.

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Shoichiro Saito, Takuji Hosoi, Heiji Watanabe, Tomoya Ono. 2009-04-16. First-Principles Study for Evidence of Low Interface Defect Density at Ge/GeO$_2$ Interfaces. https://doi.org/10.1063/1.3168501

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