CHARACTERIZATION OF AlGaAs/GaAs HBTs BY LOCALIZED FILTERED CATHODOLUMINESCENCE

AlGaAs/GaAs Heterojunction Bipolar Transistors processed with an implanted technology require a Mg implantation to contact the p-type GaAs base layer from the surface and also a low energy B implantation to eliminate the lateral diode between the n+ emitter contact layer and the converted p-type region. Low temperature cathodoluminescence spectroscopy has been used to investigate the damage induced by B implantation. An extensive analysis has then been carried out along chemical bevels to localize the damage induced by the B implantation inside the structure. Cathodoluminescence has also been used to optimize the annealing process which follows the Mg implantation in order to recover the defects induced by the implantation.