Optimal Regime for Growth of Epitaxial Germanium Layers from the Liquid Phase Based on Thermodynamic Calculations

Abstract

Thermodynamic calculations were performed to determine the optimal conditions for the growth of germanium epitaxial layers from a Ge-Sn solution (system) to a germanium substrate. The determination of the optimal conditions was based on the change in the Gibbs energy values of the system during the crystallization process and the size of the crystal-forming nanoclusters. Based on the results obtained, we determined the optimal conditions for obtaining low-dislocation, crystalline perfect germanium epitaxial layers from a liquid tin solution, and recommended starting the crystallization process at 923 K and finishing at 800 K. When the temperature drops below 800 K, the formation of Ge1-xSnx epitaxial layers from the Ge-Sn solution was observed.

Keywords

• dislocation
• epitaxial layer
• nanoclusters
• activity coefficients

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