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The Monte Carlo simulation method is used to analyze the behavior of electron and hole mobility in different nanoelectronic devices including double gate transistors and FinFETs. The impact of technological parameters on carrier mobility is broadly discussed, and its behavior physically explained. Our main goal is to show how mobility in multiple gate devices compares to that in single gate devices and to study different approaches to improve the performance of these devices. Simulations of ultrashort channel devices taking into account quantum effects are also shown. [ABSTRACT FROM AUTHOR]

Electron transport in strained double gate silicon on insulator transistors has been studied by Monte Carlo method. Poisson and Schroedinger equations have been self-consistently solved in these devices for different silicon layer thicknesses both for unstrained and strained silicon channels. The results show that the strain of the silicon layer leads to a larger population of the no-primed subbands, thus decreasing the average conduction effective mass. However, strain also contributes to a larger confinement of the charge close to the two Si/SiO2 interfaces, thus weakening the volume inversion effect, and limiting the potential increase of the phonon limited mobility. [ABSTRACT FROM AUTHOR]

In this work, a self-consistent solution of the 2D Schrödinger-Poisson equations is used to analyze Multiple-Gate MOSFETs. Classical simulations overestimate the peak density compared to quantum simulations and therefore the total electron density considered to calculate the current. The impact of the corner rounding on the electron distribution has also been analyzed. New devices, such as the Omega-gate MOSFETs have been studied as a function of the buried gate length. [ABSTRACT FROM AUTHOR]

A Quantum Ensemble Monte Carlo (QEMC) simulator is used to calculate electrical characteristics and transient response of actual nanotransistors: both sub-50 nm CMOS N-MOSFETs and ultrathin double gate SOI transistors have been deeply studied. Doping profiles and oxide thickness have been selected to cope with the available specifications of the ITRS Roadmap. The Quantum corrected Ensemble Monte Carlo simulator (QEMC) has been used to self-consistently solve the Boltzmann Transport and Poisson equations in actual devices. Quantum effects are included through the Multi-Valley Effective Conduction Band Edge (MV-ECBE) technique, and adequate approaches for phonon and surface roughness scattering have been developed to include the effects of carrier quantization in pseudo-2DEG simulations. [ABSTRACT FROM AUTHOR]

A comprehensive study of velocity overshoot and the dependences that might be established with technological parameters in symmetrical DGSOI transistors has been carried out. A one-electron Monte Carlo simulator was used to perform this work. It has been proved that velocity overshoot is dominated by the average conduction effective mass. Thus, when the silicon thickness decreases below 5 nm velocity overshoot peak increases showing the opposite behavior to electron mobility. [ABSTRACT FROM AUTHOR]

In many rat strains, C-cell hyperplasia occurs in an age-dependent manner and is often associated with multifocal C-cell carcinoma. The purpose of this study was to investigate the spectrum of spontaneous, proliferative C-cell disorders by gender in Wistar rats throughout their lifespan. The incidence of C-cell hyperplasia shows a significant increase with age ( P<0.001) and is much higher in female rats than in male rats ( P<0.05). From 3 to 24 months of life, 27.5% of female rats showed a normal C-cell pattern, 55.0% showed C-cell hyperplasia, and 17.5% showed C-cell tumors; while 57.5% of male rats showed a normal C-cell pattern, 32.5% showed C-cell hyperplasia, and 10% showed C-cell tumors. Although the overall frequency of C-cell neoplasms in females was nearly double that in males, these data are not statistically significant. However, the number of C-cell tumors showed a significant increase with age ( P<0.05). Therefore, we can conclude that there were significant differences in the incidence of the total spectrum of C-cell proliferative abnormalities in the thyroid gland of Wistar rats that were both age-dependent and gender-dependent. [ABSTRACT FROM AUTHOR]