Optical determination of strains in heterostructures: GaAs/Si as an example
Raman and photoluminescence spectroscopies are used to characterize crystalline quality
and interfacial strain in heterostructures. The effect of a biaxial stress on electronic and
vibronic energies is reviewed and then applied to the case of a GaAs layer. Measurements
on GaAs grown on Si (100) by molecular‐beam epitaxy are made over a wide temperature
range (4→ 700 K). The evolution of the strain is deduced from the shift of both the energy‐
band gaps and the long‐wavelength transverse and longitudinal‐optical‐phonon …
and interfacial strain in heterostructures. The effect of a biaxial stress on electronic and
vibronic energies is reviewed and then applied to the case of a GaAs layer. Measurements
on GaAs grown on Si (100) by molecular‐beam epitaxy are made over a wide temperature
range (4→ 700 K). The evolution of the strain is deduced from the shift of both the energy‐
band gaps and the long‐wavelength transverse and longitudinal‐optical‐phonon …