BASE TRANSIT-TIME OF GAN INGAN HETEROJUNCTION BIPOLAR-TRANSISTORS/

A theoretical analysis of the base transit time in npn GaN/InGaN heter ojunction bipolar transistor has been performed. For the analysis the effect of band-gap narrowing, carrier degeneracy, and compositional gr ading of the base region has been considered. The analysis demonstrate s that a nonuniform doping in the base region with a higher value at t he emitter edge and a lower value at the collector edge together with a compositional grading is necessary for minimizing the base transit t ime. (C) 1995 American Institute of Physics.