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Solutions to the first three moments of the Boltzmann transport equation and Poisson's equation are obtained for a permeable base transistor (PBT) using linearized, block implicit (LBI) and ADI techniques. Two level electron transfer is considered. The results of the simulations are compared to results obtained from the drift and diffusion equations. The comparison indicates that nonequilibrium transport and velocity overshoot are important in the PBT. The predicted I‐V characteristics of the device show substantially higher current levels and a higher cutoff frequency are obtained with the moment equations.

In this paper, the authors describe a more efficient and economical method for a splitting scheme for drift‐diffusion models for semiconductors. It enables one to calculate stationary and non‐stationary processes in semiconductor plasma.

The current‐voltage (Id—Vd) characteristics and microwave performance of Si1−xGex MESFETs are discussed. The 2D Poisson's equation along with the drift and diffusion equation are solved using a finite difference technique to calculate device parameters such as gm and fT. The low field carrier mobility is computed by using a single partice Monte Carlo program. In the simulation all relevant scattering mechanisms are accounted for.

Boundary limited transport in small compound semiconductor devices is studied within the self‐consistent Monte Carlo method. New stable microscopic models fully accounting for stochastic carrier exchange at boundaries have been developed for ohmic, tunneling, and Schottky barrier boundaries. These new models are demonstrated with applications to the one‐dimensional GaAs resistor, N+‐N‐N+ diode and the N+‐N Schottky diode.

A numerical implementation of a discretization scheme of the hydrodynamic model for submicron devices is described and applied to a one‐dimensional ballistic diode. The performance of the numerical method and the physical results of the simulation for different biases and lattice temperatures, and a brief comparison to Monte Carlo simulations, are also given.

With the advent of sophisticated growth techniques such as Molecular Beam Epitaxy and Metal Organic Chemical Vapor Deposition, the calculation of the energy boundstates and electron wave‐functions of the one‐electron Schrödinger equation has received a lot of attention over the last decade. With the more recent fabrication of quantum wires and dots, it seems now imperative to extend the boundstates calculation to systems containing only a few electrons. Hereafter, we investigate the effect of electron exchange and Coulomb interactions on the boundstates of a two‐electron system in a square quantum well. The technique is based on a general Alternating Direction Implicit algorithm ( T. Singh and M. Cahay, SPIE Vol. 1675, Quantum Wells and Superlattice Physics IV (1992), p.11) combined with a Fourier spectrum analysis of the two‐particle wavefunction correlation , <ψ(χ1,χ2;0)/ψ(χ1,χ2;τ)> , where χ1, χ2 are the coordinates of the two electrons. The precise location of the energy eigenvalues requires the appropriate use of window functions before calculating the Fourier transform of the correlation function. We also compare our results for the boundstate energies with those obtained using a first order time‐independent perturbation theory.

A half‐implicit absolutely stable method for 3D simulation of the transient processes in semiconductor devices is proposed. The calculations of transient processes in bipolar transistor were carried out and were compared with the results of 2D simulation.

An empirical velocity‐field relationship, based on Monte Carlo simulation, is used to modify a drift‐diffusion model for the characterization of short gate GaAs MESFET's. The modified drift‐diffusion model is used to generate both the steady‐state and the small‐signal parameters of submicron GaAs MESFET's. The current, transconductance, and cutoff frequency are compared with two‐dimensional Monte Carlo simulation results on a 0.2 µm gate‐length. The model is also used to predict measured I‐V and s‐parameters of a 0.5 µm gate‐length ion‐implanted GaAs MESFET. The comparison and the analysis made, support the accuracy of the modified drift‐diffusion simulator and makes it computationally efficient for analysis of short‐gate devices.