Random telegraphic signals (RTS) are observed in the forward‐biased dc base current of electrically stressed silicon bipolar transistors. The RTS noise in the base current is shown to originate from random trapping of electrons at the stress‐created oxide and interface traps located over the oxide‐covered emitter‐base junction space‐charge region. The observed pulse width (∼0.1–100 s), the uniform height of the pulses (∼1% of dc base current), and their dependencies on temperature andVBE(emitter/base bias voltage), exp(qVBE/nkT) withn=2, are interpreted by the two‐step model consisting of electron tunneling between the oxide and interface traps, and the recombination of Si band electrons and holes at the interface traps. ©1995 American Institute of Physics.