Optical characterization of a strained silicon quantum well on SiGe on insulator

International audienceAn 8 nm thick strained silicon layer embedded in relaxed Si0.8Ge0.2 has been grown on SiGe on insulator substrate in order to reduce the optical response of dislocations present in the SiGe virtual substrate. Photoreflectance measurement shows bandgap shrinkage at Γ point of 0.19 eV which corresponds to a 0.94% strain value close to the one measured in Raman spectroscopy. The luminescence arising only from the strained Si quantum well in high injection conditions reveals clearly two optical transitions observed at 0.959 and 1.016 eV