Using deep level transient spectroscopy, measurements were made of the defect spectrum in the collector of a n-p-n bipolar transistor following fast neutron irradiation as well as the gain on the same device. It was shown that a slow change observed in both the gain and deep level traps in the n-type collector at 300K were bistable. The transistor gain and the defects could be returned to the post-irradiation condition by forward bias at room temperature, i.e., by operating the transistor (gain) or injection through the base-collector diode (defect spectrum).

Defect-Driven Gain Bistability in Neutron Damaged, Silicon Bipolar Transistors. R.M.Fleming, C.H.Seager, D.V.Lang, E.Bielejec, J.M.Campbell: Applied Physics Letters, 2007, 90[17], 172105