Scanning x-ray microscopy: A sub-100 nm probe toward strain and composition in seeded horizontal Ge(110) nanowires

We have spatially investigated lattice spacing, twist, and bending in individual laterally (110)-oriented Ge nanowires (NWs) on pre-patterned Si(001) substrates. A combination of synchrotron-based scanning x-ray diffraction microscopy with an x-ray focus size of 50 nm and numerical finite element calculations on the elastic strain reveals a three-dimensional relaxation scenario, which becomes particularly complex next to NW nucleation points. Despite a lattice mismatch of 4.2%, lattice compliance is preserved, since strain can effectively be released close to the seeding window. Areas in the NWs other than that appear fully relaxed. The resulting NW twist, i.e., lattice rotations around the growth axis, amounts to less than 0.1 & DEG;.& nbsp;(c) 2022 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

This study spatially investigates lattice spacing, twist, and bending in laterally (110)-oriented Ge nanowires using synchrotron-based scanning x-ray diffraction microscopy and numerical finite element calculations. The results reveal a complex relaxation scenario near the nucleation points of the nanowires, but overall the lattice compliance is preserved.