Artigos

URI permanente para esta coleçãohttps://repositorio.fei.edu.br/handle/FEI/798

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 10 de 323

Junctionless nanowire transistors effective channel length extraction through capacitance characteristics
(2023-10-05) SILVA, E. M.; TREVISOLI, R.; Rodrigo Doria
© 2023 Elsevier LtdThis work aims to extract the effective channel length (LEFF) of Junctionless Nanowire Transistors (JNT) through the maximum gate capacitance of the devices. The LEFF extraction has been done by extrapolating the maximum gate capacitance as a function of the devices’ channel length (LMASK) and has shown that LEFF is around 10–15 nm longer than LMASK for devices of different channel doping concentrations.
Impact of series resistance on the drain current variability in inversion mode and junctionless nanowire transistors
(2023-10-05) SILVA, L. M. B. DA; Marcelo Antonio Pavanello; CASSÉ, M.; BARRAUD, S.; VINET, M.; FAYNOT, O.; Michelly De Souza
© 2023 Elsevier LtdThis work analyzes the influence of source-drain series resistance variability over the drain current in junctionless and inversion mode nanowire transistors. A comparison between drain current and Y-function variability is presented using experimental data of nanowires with different widths and channel lengths. The source-drain series resistance variability is also presented. The results indicates that source-drain series resistance influence is higher on drain current variability for junctionless than inversion mode nanowire transistors.
Heuristically accelerated Q-learning: A new approach to speed up reinforcement learning
(2004-01-05) Reinaldo Bianchi; RIBEIRO, C. H. C.; COSTA, A. H. R.
This work presents a new algorithm, called Heuristically Accelerated Q-Learning (HAQL), that allows the use of heuristics to speed up the well-known Reinforcement Learning algorithm Q-learning. A heuristic function H that influences the choice of the actions characterizes the HAQL algorithm. The heuristic function is strongly associated with the policy: it indicates that an action must be taken instead of another. This work also proposes an automatic method for the extraction of the heuristic function H from the learning process, called Heuristic from Exploration. Finally, experimental results shows that even a very simple heuristic results in a significant enhancement of performance of the reinforcement learning algorithm. © Springer-Verlag 2004.
Study of matching properties of graded-channel SOI MOSFETs
(2008-01-05) Michelly De Souza; FLANDRE, D.; Marcelo Antonio Pavanello
In this paper an overall analysis on the matching properties of Graded-Channel (GC) SOI MOSFETs in comparison to conventional SOI transistors is performed. Experimental results show that GC devices present poorer matching behavior in comparison to conventional SOI counterpart for equal mask channel length, whereas for same effective channel length, almost the same matching behavior. The analytical model for the drain current of GC devices is used to investigate the reasons for this matching worsening. Two-dimensional numerical simulations are used to validate the model-based analysis both in linear and saturation regions.
The Haar wavelets used how expansion function in the method of the moments in the solution of some electrostatic problems
(2010-08-05) Aldo Belardi; CARDOSO, J. R.; SARTORI, C. A. F.
This work presents the methodology from the determination the charge superficial density and electrical fields, in three simple structures to a finite straight wire, square plane plates and the capacitance between to plane plate, all finite and submitted to a constant potential. That involves the method of the moments using as expansion function the Haar wavelets instead of the pulse function, in order to reach a good precision and reducing the computational execution time. We also intend to take advantages of the wavelets application through the Cholesky decomposition, talking about formation of scattered matrixes, and the detection of nulls values.
Thin-film lateral SOI pin diodes for thermal sensing reaching the cryogenic regime
(2010-09-01) Michelly De Souza; RUE, B.; FLANDRE, D.; Marcelo Antonio Pavanello
This paper presents the performance of lateral SOI PIN diodes for temperature sensing in the range of 100 K to 400 K. Experimental results indicate that PIN diodes can be used to implement temperature sensors with high accuracy in cryogenic regime, provided that a suitable temperature range is chosen for calibration. Numerical simulations using Atlas two-dimensional simulator were performed in order to confirm this hypothesis and extend the analysis, verifying the accuracy of the existing model.
Performance of source follower buffers implemented with standard and strained triple-gate nFinFETs
(2010-09-05) Marcelo Antonio Pavanello; MARTINO, J. A.; SIMOEN, E.; ROOYACKERS, R.; COLLAERT, N.; CLAEYS, C.
In this work the application of standard and strained triple-gate FinFETs in unity-gain source-follower configuration is compared. The analysis is performed by evaluating the buffer voltage gain with respect to the fin width and channel length as well as the total harmonic distortion. It is demonstrated that the application of strained material in narrow FinFETs, when the devices are operating in double-gate mode, can be beneficial for the performance of buffers in any channel length. On the other hand, for triple-gate FinFETs or quasi-planar ones the degradation of the output conductance overcomes the transconductance improvements from strained material and the performance of standard buffers is better than of strained ones. Narrow strained buffers also offer better harmonic distortion.
Temperature and silicon film thickness influence on the operation of lateral SOI PIN photodiodes for detection of short wavelengths
(2011-09-05) Michelly De Souza; BULTEEL, O.; FLANDRE, D.; Marcelo Antonio Pavanello
This work presents an analysis of the temperature influence on the performance of a lateral thin-film SOI PIN photodiodes when illuminated by low wavelengths, in the range of blue and ultra-violet (UV). Experimental measurements performed from 100K to 400K showed that the optical responsitivity of SOI PIN photodetectors is affected by temperature change, being reduced at low and moderately high temperatures. Two-dimensional numerical simulations showed the same trends as in the experimental results, and were used both to investigate the physical phenomena responsible for the observed behavior as a function of the temperature as well as to predict the influence of silicon film thickness downscaling on the photodetector performance.
Influence of fin shape and temperature on conventional and strained MuGFETs' analog parameters
(2011-09-05) BUHLER, R. T.; Giacomini R.; MARTINO, J. A.
This work evaluates two important technological variations of Triple-Gate FETs: the use of strained silicon and the occurrence of non-rectangular body cross-section. The anaysis is focused on the electrical parameters for analog applications, and covers a temperature range from 150 K to 400 K. The comparison of the intrinsic voltage gain between the different trapezoidal fin shapes showed that the fin shape can have a major role in some analog parameters than the use of the strained silicon technology, helping to improve those parameters under certain circumstances. The highest intrinsic voltage gains were obtained for strained devices with top fin width larger than bottom at low temperature. Besides the intrinsic voltage gain, were also studied: the threshold voltage, subthreshold swing, drain induced barrier lowering, channel resistance, total harmonic distortion, transconductance, transconductance to drain current ratio, output conductance, Early voltage, drain voltage saturation and unity gain frequency.
QFT control applied to a Drive by Wire (DBW) system
(2012-01-05) Delatore F.; Fabrizio Leonardi; CARVALHO, A. T.; MORIOKA, C. A.
Tradionally, the throttle valve positioning was performed mechanically by means of a steel cable. Nowadays at the embedded system stage, an electromechanical system named as Drive by Wire (DBW) substitutes the direct positioning. The DBW is controlled by the vehicle Engine Control Unit (ECU) and is responsible to adjust the mass air flow delivered to the engine and to control the idle engine rotation. The throttle valve control is somehow a challenging task because of nonlinear phenomena caused by the spring and the gearbox. The present work aims to design a robust parametric control for a DBW system, using a plant model identified numerically at different operations points. The results show that the controller is able to deal with the nonlinear phenomena providing a reasonable performance with no steady state error and a consistent setting time.

Artigos

Navegar

Filtros

Configurações

Ordenar por

Resultados por página

Resultados da Pesquisa