Formation of Uniaxial Tensile-strained Ge by Using Micro-patterning of Ge/Si_1-xGe_x/Si Structures

抄録

  We have investigated the anisotropic strain structure of micro-patterned Ge/Si_1-xGe_x mesa lines. The elastic strain-relaxation of a Si_1-xGe_x layer by micro-patterning induces an uniaxial tensile strain into a Ge layer only for the direction perpendicular to the line. The pattern size dependence on the behavior of the elastic strain-relaxation of Si_1-xGe_x layers is analyzed by FEM. Additionally, the XRD results for micro-patterned samples suggest that the overetching depth of the Si substrate also influenced the strain-relaxation of the Si_1-xGe_x layers and the tensile-strain value of the Ge layers.