Cathodoluminescence (CL) imaging and spectroscopy have been used to characterize fully strained SiGe quantum wells grown on Si. At T≊5 K, the CL spectra contain only band edge luminescence features. Monochromatic imaging with the no-phonon line attributed to the bound excitons in the quantum well, has shown that the distribution of the luminescence from the wells is not uniform. The thinnest well (33 Å) contained a low density of nonradiative (luminescence reduction up to 100%) spots 40-100 μm in size. The thickest well (500 Å) contained similar nonradiative spots and also dark line features oriented along the 〈110〉 directions. These dark line features are areas of nonradiative recombination (up to 70%) and have been identified by transmission electron microscopy as misfit dislocations.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)