Strain relaxation by stripe patterning in Si/Si1 − xGex/Si(100) heterostructures

The relaxation of strain in Si/Si1 − xGex/Si(100) heterostructure by stripe patterning in [110] direction has been investigated using Raman scattering spectroscopy. It is found that the strain is relaxed by stripe patterning and that the degree of strain relaxation becomes larger for a narrower stripe, higher Ge fraction, and thinner capping Si layer. Even for the 5 μm-width line, the strain relaxation was observed at 0.4 μm inside of the stripe-patterned heterostructure. Therefore, it is suggested that strain relaxation in Si1 − xGex layer proceeds in the region from the stripe edge to the inner position of 0.4 μm away from the edge.