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A novel approach to many‐body quantum transport theory which emphasize the role of localized orbitals, and their lattice Fourier transforms, as dynamical basis states is given. The formalism allows for the calculations of particle quantum trajectories, describing individual elementary space and time‐dependent events in quantum processes. It is demonstrated that the particle quantum trajectories exhibit behavior quite identical to that of classical particles acted upon by a new “effective quantum force”. The present technique for calculating the quantum force can be applied to a procedure for incorporating space and time‐dependent quantum tunneling in Selfconsistent Ensembe Particle Monte Carlo (SEPMC) technique for multidimensional device analysis.

Intrinsic high‐frequency oscillations (≈2.5 THz) in current and corresponding quantum well density, which have been simulated for a fixed bias voltage in the Negative Differential Resistance (NDR) region of the Current‐Voltage (I‐V) characteristics of a Resonant Tunneling Diode (RTD), suggest an equivalent nonlinear autonomous circuit model. The intrinsic circuit parameters are calculated directly from the results of the quantum transport numerical simulations. These consist of a resistor in series with a two‐branch parallel circuit, one branch consists of a capacitor and the other branch consists of an inductor in series with a nonlinear resistor. It is however suggested that much more complex external circuit‐induced behavior can occur in real RTD experiments.

The response of a MESFET and an inverted HEMT to the impact of an a particle has been calculated by means of the Monte Carlo Particle Model, a technique for solving Boltzmann's transport and Poisson's field equation self‐consistently in space and time. The calculations show that all the terminals of the MESFET react by generating an initial current pulse followed by another; the timing of the second pulse depends on the angle of incidence of the α particle. The lattice heating rate was found to be largest at the corners of the Ohmic contacts. The HEMT, on the other hand, hardly reacts electrically to the α particle but is more likely to burn out in an a particle radiation environment because of the larger lattice heat generation taking place in the interior of the transistor. The results also support the theory of the hot‐electron induced subsurface catastrophic failure mechanism.

A two‐dimensional numerical computer simulation based on the analysis of the first three moments of the Boltzmann equation, known as the energy‐transport model, has been used to study various two‐dimensional effects on the performance of AlGaAs/GaAs heterostructure field‐effect transistor. The results are presented for half‐micron gate length. The calculation reveals significant electron current contribution coming from the AlGaAs region between the source and gate, contributing to the reduction of access resistance. As the electrons acquire large energies near the drain side edge of the gate, real‐space transfer to the AlGaAs region from the “two‐dimensional” electron gas channel occurs. However, at the drain end, the electron current is confined at the GaAs side of the heterointerface. The result shows insignificant current contribution from regions of depth greater than 0.048 µm into the undoped GaAs bulk. At room temperature, the results indicate transconductance, current gain cutoff frequency and power density about twice that which are calculated for “equivalent” GaAs MESFET, of identical structure and doping level as the heavily‐doped AlGaAs region. These results suggest that HEMT devices have the potential for providing significant sources of power at millimeter‐wave frequencies.

Standard treatments of the field emission problem typically rely on approximations to the evaluation of the Transmission Coefficient (TC). Recently, the Wigner Distribution Function (WDF) has been applied to this problem. In this paper, fast, accurate, and efficient numerical algorithms for each are presented and compared to each other and to traditional WKB and Fowler Nordheim approaches for silicon field emission. As each approach admits a trajectory interpretation, the methods for incorporating each into a larger Ensemble Particle Monte Carlo (EPMC) simulation of quantum transport are briefly discussed.

In this work we outline the methodology by which the Wigner Distribution Function (WDF) may be applied to the simulation of field emission from silicon into the vacuum so that the effects of self‐consistently calculated band bending and scattering on the current‐field characteristics may be assessed. For the first time, current saturation‐like effects are simulated. We analyze this in light of the behavior of the self‐consistent potential and density profiles at high applied fields.

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.

The purpose of this paper is to set up a consistent off‐equilibrium thermodynamic theory to deal with the self‐heating of electronic nano‐devices.

From the Bloch‐Boltzmann‐Peierls kinetic equations for the coupled system formed by electrons and phonons, an extended hydrodynamic model (HM) has been obtained on the basis of the maximum entropy principle. An electrothermal Monte Carlo (ETMC) simulator has been developed to check the above thermodynamic model.

A 1D n⁺−n−n⁺ silicon diode has been simulated by using the extended HM and the ETMC simulator, confirming the general behaviour.

The paper's analysis is limited to the 1D case. Future researches will also consider 2D realistic devices.

The non‐equilibrium character of electrons and phonons has been taken into account. In previous works, this methodology was used only for equilibrium phonons.

The purpose of this paper is to deal with the self-heating of semiconductor nano-devices.

Transport in silicon semiconductor devices can be described using the Drift-Diffusion model, and Direct Simulation Monte Carlo (MC) of the Boltzmann Transport Equation.

A new estimator of the heat generation rate to be used in MC simulations has been found.

The new estimator for the heat generation rate has better approximation properties due to reduced statistical fluctuations.