Themixed-Mode Damage Spectrum of Sige HBTs

We present a new mixed-mode stress technique for assessing the complete mixed-mode damage spectrum of SiGe HBTs, and apply it to three SiGe technology generations. We are able to distinguish four distinct regions of cross-generational SiGe HBT stress-response, identify a new low-current density damage mechanism in 3^rd generation devices, and observe for the first time a novel stress-induced annealing phenomenon. The implications of these observations are addressed.