Résumé
InGaAs/InGaAs strained layer superlattices (SLSs) are interesting candidates for optoelectronic device applications working in the 1.55 mum range. However, it was recognized very early that both the miniband widths and interband transition energies in these very shallow systems are extremely sensitive to the final value of all structural parameters. As a consequence, any unwanted modification of the composition and thickness of the wells and barriers, with respect to the nominal ones, should be carefully avoided and, at the same time, systematically checked. Toward this end, since the most useful and non-destructive techniques are X-ray and optical spectroscopy, we present in this work a comparative evaluation of their respective sensitivity.