A GaAs/AlGaAs double heterostructure-emitter bipolar transistor (DHEBT), prepared by molecular beam epitaxy, has been fabricated with improved performance. The employment of emitter edge-thinning technique has caused a significant suppression of the surface leakage current. A common-emitter current gain of up to 140 with a negligible collector offset voltage (∼40 mV) was obtained. The undesired knee-shaped characteristics and the reachthrough effect, always observed on the conventional double heterojunction bipolar transistor (DHBT), were eliminated. An interestingly bi-directional and three-terminal controlled switching phenomena may also be exhibited by this device. This gives a substantial flexibility in the device and circuit applications. The electrical performance is believed to be further improved with an adequate design to minimize the area difference between emitter-base (EB) and the base-collector (BC) junction.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)