Study of dopant-dependent band gap narrowing in compound semiconductor devices

Band gap narrowing (BGN) is one of the crucial heavy-doping effects to be considered for bipolar devices. Using a physically-based approach (E.F. Schubert, Doping in III-V Semiconductors, Cambridge University Press, 1993), we suggest a new BGN model which considers the semiconductor material and the dopant species for arbitrary finite temperatures. This unified treatment is especially useful for accurate device simulation. A comparison with experimental data and other existing models is presented and study of BGN in III-V group semiconductors is performed. Finally, as a particular example we investigated with our two-dimensional device simulator MINIMOS-NT (Simlinger et al., Simulation of submicron double-heterojunction high electron mobility transistors with MINIMOS-NT, IEEE Trans. Electron. Devices, Vol. 44, 1997, pp. 700–707), the electrical behavior of a graded composition Si/SiGe HBT using a hydrodynamic transport model.