ELECTRON TRAPPING, NITRIDE CONDUCTION, AND FORWARD GAIN INSTABILITY IN A LATERAL P-N-P DEVICE

It is found that the forward gain of a lateral p-n-p device increases under forward-bias stress conditions. The phenomenon has been characterized as a function of collector-base voltage, emitter current, and stress temperature. The results are interpreted as electron trapping at the interface between the passivation oxide and a silicon nitride overlayer. The trapping behavior is further modified by the finite conductivity of the silicon nitride. A quasi-empirical model for the effect is developed incorporating the hot-electron injection and the nitride conduction. © 1990 IEEE