Segregation of Si dgr; doping in GaAshyphen;AlGaAs quantum wells and the cause of the asymmetry in the currenthyphen;voltage characteristics of intersubband infrared detectors

摘要

Dopant segregation in the well region of a multiple quantum well intersubband photodetector can cause an asymmetry in the observed forward and reverse currenthyphen;voltage characteristics. We compensate for the segregation by shifting the position of the Si dgr; doping in the well and model the effect with good agreement for a range of shift values. For samples grown at a substrate temperature of 605thinsp;deg;C, we find that the observed behavior is best described by assuming that the Si dgr;hyphen;doping profile smears in the growth direction resulting in an asymmetric broadening of about 27 Aring;.