Published online by Cambridge University Press: 15 February 2011
Doped GexSi1−x/Si multiple quantum well structures have been grown by UHV/CVD and characterized by various techniques. SIMS and X- ray confirm the intended modulation of germanium and boron concentrations, and photoluminescence has been used to assess material quality. Strong free- carrier absorption has been observed at normal incidence in some samples. The results suggest that doping intermediate between 4 × 1018 cm−3 and 4 × 1019 cm−3 is necessary for useful detectors.