SINGLE AND MULTIBAND MODELING OF QUANTUM ELECTRON-TRANSPORT THROUGH LAYERED SEMICONDUCTOR-DEVICES

Non-equilibrium Green function theory is formulated to meet the three main challenges of high bias quantum device modeling: self-consistent charging, incoherent and inelastic scattering, and band structure. The theory is written in a general localized orbital basis using the exam ple of the zinc blende lattice. A Dyson equation treatment of the open system boundaries results in a tunneling formula with a generalized F isher-Lee form for the transmission coefficient that treats injection from emitter continuum states and emitter quasi-bound states on an equ al footing. Scattering is then included. Self-energies which include t he effects of polar optical phonons, acoustic phonons, alloy fluctuati ons, interface roughness, and ionized dopants are derived. Interface r oughness is modeled as a layer of alloy in which the cations of a give n type cluster into islands. Two different treatments of scattering; s elf-consistent Born and multiple sequential scattering are formulated, described, and analyzed for numerical tractability. The relationship between the self-consistent Born and multiple sequential scattering al gorithms is described, and the convergence properties of the multiple sequential scattering algorithm are numerically demonstrated by compar ing with self-consistent Born calculations. (C) 1997 American Institut e of Physics.