A computationally efficient non-parabolic bandstructure model for quantum transport simulations

With the increased focus on III-V materials as potential candidates for next-generation nanotransistors advanced bandstructure models going beyond the parabolic band approximation are required to ensure accurate device simulations. For that purpose we present in this paper a quantum transport approach that relies on the effective mass approximation extended with a non-parabolic (NP) correction of the electron bandstructure. This scheme does not only properly account for the NP effects present in the thermionic current of transistors, but also in their source-to-drain tunneling leakage. The NP model is validated by simulating an In_0.53Ga_0.47As double-gate ultra-thin-body transistor with different gate lengths ranging from 15 down to 5 nm. An excellent agreement with full-band results is demonstrated in all the cases.