Simulation of DC and RF Performance of the Graphene Base Transistor

We examined the DC and RF performance of the graphene base transistor (GBT) in the ideal limit of unity common base current gain. To this purpose, we developed a model to calculate the current–voltage characteristics of GBTs with semiconductor or metal emitter taking into account space charge effects in the emitter–base and base–collector dielectrics that distort the potential profile and limit the upper value of fT. Model predictions are compared with available experiments. We show that, in spite of space charge high current effects, optimized GBT designs still hold the promise to achieve intrinsic cutoff frequency in the terahertz region, provided that an appropriate set of dielectric and emitter materials is chosen.