Electron transport across the base of InP/InGaAs heterojunction bipolar transistors is examined by Monte Carlo simulation. The base transit times and electron distribution functions are examined as a function of basewidth. Clear ballistic behavior is observed only for extremely thin bases (much less than 100 A). Over the range of basewidths of interest for devices, base transport appears diffusive, but the electrons are very far from thermal equilibrium. The diffusive behavior is shown to arise from the sensitivity of the steady-state carrier population to small amounts of large-angle scattering.
Date of this Version
Appl. Phys. Lett. 61 (1992); doi: 10.1063/1.107886
Copyright (1992) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters 61 (4) 1992 and may be found at http://dx.doi.org/10.1063/1.107886. The following article has been submitted to/accepted by Applied Physics Letters. Copyright (1993) Paul Dodd and Mark Lundstrom. This article is distributed under a Creative Commons Attribution 3.0 Unported License.