Indra Nur Adisusilo

Impact of quasi-ballistic phonon transport on thermal properties in nanoscale devices: A Monte Carlo approach

In this work, a Monte Carlo simulation method is applied to study the phonon transport in nanoscale Si devices, and the impact of quasi-ballistic transport on the heat conduction properties in FinFETs is investigated. It is shown that the conventional method based on Fourier law significantly overestimates the heat flux from the Fin edge to the metal contact, which may result in the underestimation of the hot spot temperature.

Analysis of heat conduction property in FinFETs using phonon Monte Carlo simulation

A phonon transport simulator using a Monte Carlo method is used to analyze the heat conduction properties in FinFET structure. We compare the simulation results to those obtained from the conventional heat conduction equation based on the Fouriers law, and discuss about the discrepancies attributed to ballistic transport effect. We also analyze the impact of additional heat path through gate contact, and show that it has a less significant but non-negligible contribution which could slightly reduce the hot spot temperature.

Monte Carlo simulation of thermal conduction in silicon nanowires including realistic phonon dispersion relation

Monte Carlo simulation is performed to solve the phonon Boltzmann transport equation in silicon nanowires, and the thermal conductivity at various temperatures is calculated. By taking account of the realistic phonon dispersion relation, it is revealed that the experimental data for relatively thick wires with diameters of 37–115 nm are well reproduced by simply assuming completely diffuse scattering at the wire surface. On the other hand, when the approximated dispersion curves fitted to the [100] direction are used, the simulation underestimates the thermal conductivity mainly owing to the inaccurate modeling of the transverse acoustic branch around W, U, and K points, and in this case the partial specularity should be introduced in the boundary scattering mechanism to obtain agreement with the measured data.

Coupled Monte Carlo simulation of transient electron-phonon transport in small FETs

Using a coupled Monte Carlo technique for solving both electron and phonon Boltzmann transport equations, the transient electrothermal simulation of nanoscale FETs is performed. It is shown that the time constants for the electron and phonon transport are different in order of magnitude, and the self-heating has little impact on digital circuit delay, while it would affect the bias temperature instability because of the long decay time of the created hot spot. The effectiveness of introducing the lightly doped drain structure is also discussed to reduce the hot spot temperature.

Monte Carlo Simulation of Phonon Transport in Silicon Nanowires Including Realistic Dispersion Relation

Monte Carlo simulations are performed to solve the phonon Boltzmann transport equation in silicon nanowires, and the thermal conductivity is analyzed. By taking account of the realistic phonon dispersion relation, it is revealed that the experimental characteristics are well reproduced by simply assuming the completely diffusive scattering at the wire surface without introducing any fitting parameters regarding specularity.

Monte carlo simulation of seebeck coefficient of Si nanostructure with barrier layers

We numerically investigate the thermoelectric properties of Si nanostructures using Monte Carlo method coupled with one-dimensional Poisson equation. It is demonstrated that the barrier structure give rise to more pronounced electromotive force. This is probably because the barriers only allowing high energy electrons to pass through, which results in so-called energy filtering effect.

Simulation Study on Quasi-Ballistic Heat Transfer Effect in FinFETs

Yoshinari Kamakura, Kentaro Kukita, Indra Nur Adisusilo, Shunsuke Koba, and Hideaki Tsuchiya Division of Electrical, Electronic and Information Engineering, Osaka University, Suita, Osaka 565-0871, Japan Phone: +81-6-6879-4850 E-mail: kamakura@si.eei.eng.osaka-u.ac.jp Japan Science and Technology Agency (JST), CREST, Kawaguchi, Saitama 332-0012, Japan Department of Electrical and Electronic Engineering, Kobe University, Kobe 657-8501, Japan