1,721,044 research outputs found
Trade-off between Electron Velocity and Density of States in Ballistic nano-MOSFETs
No full textThis paper presents an analytical model for the on-current
(ION) of ballistic MOSFETs that points out how the reduction
of the in-plane masses implies a trade-off between
the increase of the electron velocity and the reduction of
the 2D Density of States (D2D). Numerical simulations
confirm the analytical results and demonstrate that the
ION is deteriorated for materials with a very small D2D
Analytical models for the insight into the use of alternative channel materials in ballistic nano-MOSFETs
No full text
A Quantitative Error Analysis of the Mobility Extraction According to the Matthiessen Rule in Advanced MOS Transistors
No full textThis paper presents a quantitative analysis of the errors produced by the Matthiessen rule in the extraction of the inversion-layer mobility in metal-oxide-semiconductor transistors. We show that the Matthiessen rule results in large inaccuracies in the mobility extraction, and most of all, it can lead to wrong trends, namely, to an incorrect dependence of the mobility on the temperature or the strain level. Consequently, when the Matthiessen rule is used to infer a given mobility component from the experiments, the inaccuracy of the extraction procedure can yield apparent discrepancies between experiments and simulations. Our results demonstrate that the mobility components extracted from the measurements by using the Matthiessen rule should not be regarded as experimental data because the extraction procedure relies on assumptions that are not fulfilled in most practical cases
Revised analysis of Coulomb scattering limited mobility in biaxially strained silicon MOSFETs
No full textWe present a simulation study of the dependence
of the Coulomb limited mobility on the biaxial strain in -type
(001) Si MOSFETs. By using a model based on the Momentum
Relaxation Time (MRT) approximation, we first reproduce fairly
well a wide set of published experiments, then we use our
simulations to explain the dependence on the strain of the
mobility limited by interface states and substrate impurities.
Differently from the experiments, the MRT approach allows us
to study the different mobility components without resorting to
the Matthiessen’s rule, which can lead to large errors in the
extrated mobility. Simulations indicate that the strain reduces
the interface state limited mobility, while it leaves essentially
unchanged the substrate impurity limited mobility
Effects of Thermal Treatments on the Trapping Properties of HfO2 Films for Charge Trap Memories
No full textThe charge trapping properties of HfO2 thin films for application in charge trap memories are investigated as a function of high-temperature postdeposition annealing (PDA) and oxide thickness in the TaN/Al2O3/HfO2/SiO2/Si structure. The trap density (NT) in HfO2, extracted by simulating the programming transient, is in the 1019-1020 cm(-3) range, and it is related to film thickness and PDA temperature. Diffusion phenomena in the stack play a significant role in modifying NT in HfO2 and the insulating properties of the Al2O3 layer. The memory performances for 1030 degrees C PDA are promising with respect to standard stacks featuring Si3N4. (C) 2012 The Japan Society of Applied Physic
Backscattering and common-base current gain of the Graphene Base Transistor (GBT)
Full text linkIn this paper, we investigate electron transport and electron scattering in the insulators of the Graphene Base Transistor (GBT) by means of a Monte Carlo transport model. We focus on electron backscattering in the base-collector insulator as the possible root cause of the large experimental base current and small measured common-base current gain (αF) of GBTs. Different GBT structures have been simulated and the impact of the scattering parameters on the base current is analyzed. Simulated backscattering-limited αF values are found to be much higher than available experimental data, suggesting that state-of-the-art technology is still far from being optimized. However, those simulated αF values can be low enough to limit the maximum achievable GBT performance
Experimental procedure for accurate trap density study by low frequency charge pumping measurements
No full textImportant experimental artifacts due to the gate leakage are identified during Low Frequency Charge Pumping (LFCP) experiments performed on SNOS cells to probe the SiN traps. Gate leakage is shown to impair the LFCP data detected at the S/D and bulk terminals and detailed experimental analysis is carried out on SNOS and MOSFETs to investigate how the effect of the gate leakage can be compensated for to recover reliable LFCP measurements
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