Strain and Lattice Orientation Distribution in SiN/Ge CMOS Compatible Light Emitting Microstructures by Quick X-ray Nano-diffraction Microscopy

This paper presents a study of the spatial distribution of strain and lattice orientation in CMOS-fabricated strained Ge microstripes using high resolution x-ray micro-diffraction (µ-HRXRD). The recently developed model-free characterization tool, based on a quick scanning x-ray diffraction microscopy technique can image strain down to levels of 10-5 (Δa/a)with a spatial resolution of ~0.5 µm. Strain and lattice tilt are extracted using the strain and orientation calculation software package X-SOCS. The obtained results are compared with the biaxial strain distribution obtained by lattice parameter-sensitive µ-Raman and µ-photoluminescence measurements. The experimental data are interpreted with the help of finite element modeling (FEM) of the strain relaxation dynamics in the investigated structures.