Performance and Advantages of BICFETs Versus HBT's.

The BICFET is a new form of bipolar transistor which offers superior performance for III-V bipolar integrated circuits and several unique advantages over known approaches for optoelectronic integration. The BICFET does not have a base. Instead, the control (or biasing) charge is confined to the inversion channel at a heterojunction interface which is accessed by a source self-aligned to the emitter. The channel is induced by a charge sheet located in the depleted barrier section of the emitter. Significant advantages are expected for the BICFET vs the HBT when the N-channel BICFET is compared to the NPN HBT. These advantages will be discussed and accrue from the high channel mobility and high G in the N channel BICFET which lead to a superior R sub N. G product and a superior f sub t. An N channel BICFET has been demonstrated in GaAs/AlGaAs.