Relation between the collector current and the two-dimensional electron gas stored in the base-collector heterojunction notch of InAlAs/InGaAs/InAlGaAs DHBTs

From the Gummel plots of InAlAs/InGaAs/In0.52AlxGa0.48-xAs double heterojunction bipolar transistors (DHBTs), the relationship between the collector current and the density of the two-dimensional electron gas (2DEG) stored in the base-collector (B-C) heterojunction notch is found to be an exponential function which stems from the thermionic emission escaping process of the 2DEG. © 1995.