Structural Analyses Of Strained Sige Wires Formed By Hydrogen Thermal Etching And Ge-condensation Processes

摘要

Strained SiGe-wire structures formed by a thermal oxidation of SiGe-on-insulator (SGOI) fins after an anisotropic gas etching in atmospheric hydrogen are investigated in terms of morphology, strain, and crystalline defects. It is found that vertical and smooth {110} sidewalls emerged on the SGOI fins after the hydrogen etching and that the SiGe wires consisted of a Si-rich core region and a surrounding Ge-rich layer formed by the Ge-condensation mechanism through the oxidation. Detailed strain analyses reveal that uniaxial and compressive strain accumulated in the Ge-rich layer via an elastic lattice deformation without generating dislocations.