Numerical investigations of the strain behavior in nanoscale patterned strained silicon structures

The physical properties of materials can be manipulated by applying stress or strain. For instance, the controlled introduction of strain in silicon (Si) devices was found to increase the charge careers mobility and modify the Si optical properties. The exploitation of this potential technology raises fundamental questions on strain and stress stability and behavior during the fabrication and processing of strained Si devices. In this paper, we address this issue and provide detailed three-dimensional finite element simulations of strain redistribution upon nanoscale patterning that is a crucial step in the fabrication of devices. The shown calculated results give valuable insights into the relaxation phenomenon of nano-scale strained silicon mesa-structures and point out ways to modify the strain field in one-dimensional optical micro-cavity waveguides based on photonic crystal designs. Our calculations are augmented by experimental data obtained by UV ¿-Raman spectroscopy analysis.