Electroluminescence from the base of a GaAs/AlGaAs double heterojunction bipolar transistor

Abstract
We have measured the electroluminescence spectrum of a double heterojunction bipolar transistor and found that a potential well formed at the base-collector junction acts as a preferential trap of low-energy electrons in the base. At high injection current densities the trap saturates. The subsequent buildup of carriers in the base changes the transistor turn-on characteristics.