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Dissertations / Theses on the topic 'Short-channel'
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1
APPASWAMY, ARAVIND C. "SIMULATION OF SHORT CHANNEL AlGaN/GaN HEMTs." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109277211.
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Acovic, Alexandre Acović Alexandre. "Hot electron degradation in short-channel MOS transitors /." [S.l.] : [s.n.], 1990. http://library.epfl.ch/theses/?nr=825.
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Mohamed, Nagm Eldin. "Leakage power proliferation in short-channel cache memories /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456292251&sid=9&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Knoch, Joachim. "Modeling and realization of an ultra short channel MOSFET." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963276026.
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Kendall, James D. (James Douglas) 1959 Carleton University Dissertation Engineering Electrical. "Two-dimensional analytical modelling of the short-channel mosfet." Ottawa.:, 1987.
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Liang, Xiaoping. "Analytical modeling of short channel effects in double gate MOSFET." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3204577.
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Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed April 4, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Karabatsos, Christos P. Carleton University Dissertation Engineering Electrical. "Investigation of the gate capacitance characteristics of short channel MOSFETs." Ottawa, 1989.
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Naghavi, Hananeh Sadat. "Evaluation of channel congestion in dedicated short-range communication networks." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/81196/1/Hananeh_Naghavi_Thesis.pdf.
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This thesis presents a novel idea for an adaptive prioritized cross-layer design (APCLD) control algorithm to achieve comprehensive channel congestion control for vehicular safety communication based on DSRC technology. An appropriate evaluation metric and two control parameters have been established. Simulation studies have evaluated the DSRC network performance in different traffic scenario and under different channel conditions. The APCLD algorithm is derived from the results of the simulation analysis.
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Gangadharan, Divya. "Simulation Study of Device Characteristics and Short Channel Effects of Nanoscale Germanium Channel Double-Gate MOSFETs." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1226530654.
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Plourde, Eric. "Bayesian short-time spectral amplitude estimators for single-channel speech enhancement." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66864.
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Single-channel speech enhancement algorithms are used to remove background noise in speech. They are present in many common devices such as cell phones and hearing aids. In the Bayesian short-time spectral amplitude (STSA) approach for speech enhancement, an estimate of the clean speech STSA is derived by minimizing the statistical expectation of a chosen cost function. Examples of such estimators are the minimum mean square error (MMSE) STSA, the β-order MMSE STSA (β-SA), which includes a power law parameter, and the weighted Euclidian (WE), which includes a weighting parameter. This thesis analyzes single-channel Bayesian STSA estimators for speech enhancement with the aim of, firstly, gaining a better understanding of their properties and, secondly, proposing new cost functions and statistical models to improve their performance. In addition to a novel analysis of the β-SA estimator for parameter β ≤ 0, three new families of estimators are developed in this thesis: the Weighted β-SA (Wβ-SA), the Generalized Weighted family of STSA estimators (GWSA) and a family of multi-dimensional Bayesian STSA estimators. The Wβ-SA combines the power law of the β-SA and the weighting factor of the WE. Its parameters are chosen based on the characteristics of the human auditory system which is found to have the advantage of improving the noise reduction at high frequencies while limiting the speech distortions at low frequencies. An analytical generalization of a cost function structure found in many existing Bayesian STSA estimators is proposed through the GWSA family of estimators. This allows a unification of Bayesian STSA estimators and, moreover, provides a better understanding of this general class of estimators. Finally, we propose a multi-dimensional family of estimators that accounts for the correlated frequency components in a digitized speech signal. In fact, the spectral components of the cleanLes algorithmes de rehaussement de la parole à voie unique sont utilisés afin de réduire le bruit de fond d'un signal de parole bruité. Ils sont présents dans plusieurs appareils tels que les téléphones sans fil et les prothèses auditives. Dans l'approche bayésienne d'estimation de l'amplitude spectrale locale (Short-Time Spectral Amplitude - STSA) pour le rehaussement de la parole, un estimé de la STSA non bruitée est déterminé en minimisant l'espérance statistique d'une fonction de coût. Ce type d'estimateurs incluent le MMSE STSA, le β-SA, qui intègre un exposant comme paramètre de la fonction de coût, et le WE, qui possède un paramètre de pondération.Cette thèse étudie les estimateurs bayésiens du STSA avec pour objectifs d'approfondir la compréhension de leurs propriétés et de proposer de nouvelles fonctions de coût ainsi que de nouveaux modèles statistiques afin d'améliorer leurs performances. En plus d'une étude approfondie de l'estimateur β-SA pour les valeurs de β ≤ 0, trois nouvelles familles d'estimateur sont dévelopées dans cette thèse: le β-SA pondéré (Weighted β-SA - Wβ-SA), une famille d'estimateur du STSA généralisé et pondéré (Generalized Weighted STSA - GWSA) ainsi qu'une famille d'estimateur du STSA multi-dimensionnel.Le Wβ-SA combine l'exposant présent dans le β-SA et le paramètre de pondération du WE. Ses paramètres sont choisis en considérant certaines caractéristiques du système auditif humain ce qui a pour avantage d'améliorer la réduction du bruit de fond à hautes fréquences tout en limitant les distorsions de la parole à basses fréquences. Une généralisation de la structure commune des fonctions de coût de plusieurs estimateurs bayésiens du STSA est proposée à l'aide de la famille d'estimateur GWSA. Cette dernière permet une unification des estimateurs bayésiens du STSA et apporte une meilleure compréhensio
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McPate, Mark John William. "hERG potassium channel electrophysiology and pharmacology in the short QT syndrome." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486078.
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K+ channels mediating the rapid delayed rectifier current (lKr) are encoded by human ether-a-go-go-related gene (hERG) and play an important role in determining cardiac action potential (AP) repolarisation and the QT interval of the electrocardiogram. A gain-of-function hERG mutation (N588K) is associated with variant 1 of the Short QT syndrome (SQT1), which is characterised by short QT intervals «320 ms) and increased risk of cardiac arrhythmias and sudden death. Using whole-cell patch-clamp recordings ofhERG current (lhERG) from Chinese Hamster Ovary cells expressing WildType (WT) or N588K-hERG at 37°C, I investigated the effects of the N588K mutation on hERG channel electrophysiology and pharmacology. The N588K mutation produced a -+60 mV shift in IhERG availability, without concomitant alterations ofthe voltage-dependence of activation or deactivation kinetics OfIhERG. N588K IhERG peaked much earlier than did WT IhERG during guinea-pig and human ventricular AP command waveforms. The N588K mutation also resulted in IhERG peaking earlier during atrial and Purkinje fibre AP commands. MiRP1 co-expression with hERG had little effect on the timing ofpeak repolarising current during AP commands, but did affect maximal IhERG density. Results of experiments using paired AP waveforms raise the possibility that the potentially protective role ofhERG against premature depolarisations may to an extent be compromised for N588K-hERG. The N588K mutation differentially attenuated IhERG block of selected antiarrhythmic drugs. My data indicate that in addition to quinidine, disopyramide and amiodarone may be useful pharmacological treatments for SQT1. Co-expression ofhERG-1a with hERG-1b accelerated WT and N588K IhERG deactivation kinetics and for N588K increased attenuation of inactivation compared to hERG-1a alone. The differences in IhERG-Iallb kinetics as a result of the N588K mutation did not greatly influence currents during AP command waveforms, except that peak repolarising current occurred earlier during the AP than for hERG 1a alone.
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Jakob, Markus Prüfer. "Compact DC Modelling of Short-Channel Effects in Organic Thin-Film Transistors." Doctoral thesis, Universitat Rovira i Virgili, 2022. http://hdl.handle.net/10803/673905.
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Els transistors orgànics de capa fina (TFT) són dispositius prometedors per a les pantalles flexibles de matriu activa i
els conjunts de sensors, ja que poden fabricar-se a temperatures de procés relativament baixes i, per tant, no sols en
vidre, sinó també en substrats polimèrics. Per a millorar el rendiment dinàmic dels dispositius i circuits TFT , una
reducció agressiva de la longitud de canal provoca efectes extrínsecs en els dispositius que han de ser capturats per
models compactes.
Aquesta tesi presenta models analítics, basats en la física, de la degradació de la pendent subumbral, el roll-off del
voltatge llindar i l'efecte DIBL en TFTs coplanars i escalonats que poden ser implementats en qualsevol model
compacte de corrent continu arbitrari que estigui definit pel voltatge llindar i la pendent subumbral. Per tant, l'equació
diferencial de Laplace es resol per a la geometria coplanar i escalonada aplicant la transformación Schwarz-Cristoffel.
Les solucions del potencial serveixen de base per a la definició de les equacions del model. A més, es desenvolupen
models compactes de les barreres Schottky dependents de la polarització en les interfícies font/semiconductor i
drenador/semiconductor en els TFT coplanars i escalonats, que modelen la injecció i l'ejecció de portadors de càrrega,
respectivament, com a corrent d'emissió termoiònica.Los transistores orgánicos de capa fina (TFT) son dispositivos prometedores para las pantallas flexibles de matriz activa y los conjuntos de sensores, ya que pueden fabricarse a temperaturas de proceso relativamente bajas y, por tanto, no sólo en vidrio, sino también en sustratos poliméricos. Para mejorar el rendimiento dinámico de los dispositivos y circuitos TFT, una reducción agresiva de la longitud de los canales provoca efectos extrínsecos en los dispositivos que tienen que ser capturados por modelos compactos. Esta tesis presenta modelos analíticos, basados en la física, de la degradación de la pendiente subumbral, el roll-off del voltaje umbral y el efecto DIBL en TFTs coplanares y escalonados que pueden ser implementados en cualquier modelo compacto de corriente continua arbitrario que esté definido por el voltaje umbral y la pendiente subumbral. Por lo tanto, la ecuación diferencial de Laplace se resuelve para la geometría coplanar y escalonada aplicando la transformación Schwarz-Christoffel. Las soluciones del potencial sirven de base para la definición de las ecuaciones del modelo. Además, se desarrollan modelos compactos de las barreras Schottky dependientes de la polarización en las interfaces fuente/semiconductor y drenador/semiconductor en los TFT coplanares y escalonados, que modelan la inyección y la eyección de portadores de carga, respectivamente, como corriente de emisión termoiónica
Organic thin-film transistors (TFTs) are promising devices for flexible active-matrix displays and sensor arrays, since they can be fabricated at relatively low process temperatures and thus not only on glass, but also on polymeric substrates. In order to improve the dynamic TFT and circuit performance, an aggressive reduction of the channel length causes extrinsic de-vice effects that have to be captured by compact models. This dissertation presents analytical, physics-based models of the subthreshold-swing degra-dation, the thresholdvoltage roll-off and DIBL effects in coplanar and staggered TFTs that can be implemented in any arbitrary compact dc model that are defined by the threshold voltage and the subthreshold swing. Therefore, Laplace’s differential equation is solved for the coplanar and staggered geometry by applying the Schwarz-Christoffel transformation. The potential solutions serve as a basis for the definition of the model equations. Further-more, compact models of the biasdependent Schottky barriers at the source/semiconductor and drain/semiconductor interfaces in coplanar and staggered TFTs are derived, which model the charge carriers injection and ejection, respectively, as thermionic emission cur-rent. Thereby, in case of the source barrier, the Schottky barrier lowering effect due to im-age charges is captured and therefore, an analytical expression of the electric field at the source barrier is derived.
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Allbutt, Geoffrey Julian. "Tuning high-frequency g[subscript]m-C filters based on short channel MOSFETs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq22265.pdf.
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Roll, Guntrade [Verfasser], and Lothar [Akademischer Betreuer] Frey. "Leakage Current and Defect Characterization of Short Channel MOSFETs / Guntrade Roll. Betreuer: Lothar Frey." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/1028392605/34.
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Roll, Guntrade Verfasser], and Lothar [Akademischer Betreuer] [Frey. "Leakage Current and Defect Characterization of Short Channel MOSFETs / Guntrade Roll. Betreuer: Lothar Frey." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/1028392605/34.
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Shoredits, Andreas. "Urban Stream Channel Geomorphology: Investigating the Short-Term Channel Stability and Bed-Material Transportation within a Rehabilitated Urban Stream Reach in DeKalb County, Georgia." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/geosciences_theses/55.
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Rivers and streams are sensitive to alterations in their watersheds and one of the greatest disturbances is from urban development. An urban stream channel in the Atlanta metropolitan area in the Georgia Piedmont was studied to establish the nature of adjustment the channel form was experiencing. This study compared a degraded channel with a channel influenced by stabilization efforts in the same stream reach, in order to investigate the behavior of channel adjustments towards a greater stability. Measurements of the short-term changes in channel cross-sectional area and bed-material volume, following a series of threshold flow events, were taken in the reach and the variation in bed sediment texture was also investigated. Results showed that channel banks were stable compared to more mobile beds and that urban effects continued to dictate sedimentation. Rehabilitation measures were aggrading channels in their reaches and were likely perpetuating the instability of upstream channels.
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Rieser, Christian James. "Design and Implementation of a Swept Time Delay Short Pulse (SSTDSP) Wireless Channel Sounder for LMDS." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35113.
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This thesis describes the theoretical development, design, and implementation of a novel measurement system, called a Sampling Swept Time Delay Short Pulse (SSTDSP) wireless channel sounder, capable of real time in field performance characterization of high speed fixed wireless links. The SSTDSP sounder has been designed to provide vital performance metrics for fixed point high data rate applications in the 28 GHz LMDS band at a fraction of the cost and complexity of existing wideband channel sounders.
The SSTDSP sounder monitors the behavior of the LMDS channel by sampling the impulse response of the channel in real time. This digitized impulse response is used to assemble a power delay profile and render real-time channel performance metrics such as the mean excess delay, RMS delay spread, maximum excess delay for a given multipath threshold, and coherence bandwidth. The SSTDSP sounder is capable of recording these metrics through three modes of operation - continuous channel monitoring, single instant channel snapshot, or data logging. Swept time delay time dilation processing is combined with precise sample and hold gating to reduce the analog to digital converter sampling rate required to digitize the nanosecond short pulses from 2 Gsps to 1 Msps, while retaining the required effective Nyquist sampling rate of 2 Gsps. This dramatically reduces the memory, digital signal processing, and data logging storage requirements as well as the overall cost of the sounder system.
The thesis presents the theory behind channel sounding and discusses whether there is a "bounce path" available to LMDS. Several existing channel sounding methods are compared for this application. A number of specific design and performance criteria from each of these methods are synthesized to produce the Sampling Swept Time Delay Short Pulse Sounder architecture. The design and implementation process used to realize the SSTDSP sounder is presented, including a system overview, module details, and algorithm development details. A calibration and measurement test procedure is outlined and system verification results are presented.
Current work in progress on the test platform and future improvements to the modular system are outlined, as well as conclusions and future implications of the system.
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Shelley, Valerie Anderson 1957. "Validity of the Jain and Balk analytic model for two-dimensional effects in short channel MOSFETS." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276801.
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The Jain and Balk analytic model for two-dimensional effects in short channel MOSFETS is investigated. The effects considered are Drain Induced Barrier Lowering, DIBL, and the maximum electric field, Emax, which influences Drain Induced High Field, DIHF. A scaled short channel design is used as the basis for the investigation. Cases are numerically simulated using the MINIMOS program. DIBL and Emax are calculated using the Jain and Balk model. Model values are compared to numerical simulation values. Results show the model consistently overestimates DIBL. Also, the range for which the model closely estimates Emax is found. Variation in Emax with change of junction depth Xj is investigated. The electric field, Ex, as it varies with depth in the channel is investigated, and compared to the Jain and Balk approximation. The deviations suggest that the model must break down for short channels.
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Rowe, Christopher D. "Channel Propagation Model for Train to Vehicle Alert System at 5.9 GHz using Dedicated Short Range Communication." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73178.
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The most common railroad accidents today involve collisions between trains and passenger vehicles at railroad grade crossings [1][2]. Due to the size and speed of a train, these collisions generally result in significant damage and serious injury. Despite recent efforts by projects such as Operation Lifesaver to install safety features at grade crossings, up to 80% of the United States railroad grade crossings are classified as 'unprotected' with no lights, warnings, or crossing gates [2]. Further, from January to September 2012, nearly 10% of all reported vehicle accidents were a result of train-to-vehicle collisions. These collisions also accounted for nearly 95% of all reported fatalities from vehicular accidents [2].
To help provide a more rapidly deployable safety system, advanced dedicated short range communication (DSRC) systems are being developed. DSRC is an emerging technology that is currently being explored by the automotive safety industry for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications to provide intelligent transportation services (ITS). DSRC uses WAVE protocols and the IEEE 1609 standards. Among the many features of DSRC systems is the ability to sense and then provide an early warning of a potential collision [6]. One potential adaption for this technology is for use as a train-to-vehicle collision warning system for unprotected grade crossings. These new protocols pose an interesting opportunity for enhancing cybersecurity since terrorists will undoubtedly eventually identify these types of mass disasters as targets of opportunity.
To provide a thorough channel model of the train to vehicle communication environment that is proposed above, large-scale path loss and small scale fading will both be analyzed to characterize the propagation environment. Measurements were collected at TTCI in Pueblo Colorado to measure the received signal strength in a train to vehicle communication environment. From the received signal strength, different channel models can be developed to characterize the communication environment.
Documented metrics include large scale path loss, Rician small scale fading, Delay spread, and Doppler spread. An analysis of the DSRC performance based on Packet Error Rate is also included.Master of Science
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Dangerfield, C. E. "Stochastic models of ion channel dynamics and their role in short-term repolarisation variability in cardiac cells." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:cd0be850-1ff0-4792-8171-438ff8fc0161.
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Sudden cardiac death due to the development of lethal arrhythmias is the dominant cause of mortality in the UK, yet the mechanisms underlying their onset, maintenance and termination are still poorly understood. Therefore biomarkers are used to determine arrhythmic risk within patients and of new drug compounds. In recent years, the magnitude of variations in the length of successive beats, measured over a short period of time, has been shown to be a powerful predictor of arrhythmic risk. This beat-to-beat variability is thought to be the manifestation of the random opening and closing dynamics of individual ion channels that lie within the membrane of cardiac cells. Computational models have become an important tool in understanding the electrophysiology of the heart. However, current state-of-the-art electrophysiology models do not incorporate this intrinsic stochastic behaviour of ion channels. Those that do use computationally costly methods, restricting their use in complex tissue scale simulations, or employ stochastic simulation methods that result in negative numbers of channels and so are inaccurate. Therefore, using current stochastic modelling techniques to investigate the role of stochastic ion channel behaviour in beat-to-beat variability presents difficulties. In this thesis we take a mathematically rigorous and novel approach to develop accurate and computationally efficient models of stochastic ion channel dynamics that can be incorporated into existing electrophysiology models. Two different models of stochastic ion channel behaviour, both based on a system of stochastic differential equations (SDEs), are developed and compared. The first model is based on an existing SDE model from population dynamics called the Wright-Fisher model. The second approach incorporates boundary conditions into the SDE model of ion channel dynamics that is obtained in the limit from the discrete-state Markov chain model, and is called a reflected SDE. Of these two methods, the reflected SDE is found to more accurately capture the stochastic dynamics of the discrete-stateMarkov chain, seen as the ‘gold-standard’ model and also provides substantial computational speed up. Thus the reflected SDE is an accurate and efficient model of stochastic ion channel dynamics and so allows for detailed investigation into beat-to-beat variability using complex computational electrophysiology models. We illustrate the potential power of this method by incorporating it into a state-of-the-art canine cardiac cell electrophsyiology model so as to explore the effects of stochastic ion channel behaviour on beat-to-beat variability. The stochastic models presented in this thesis fulfil an important role in elucidating the effects of stochastic ion channel behaviour on beat-to-beat variability, a potentially important biomarker of arrhythmic risk.
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Pacheco-Sánchez, Aníbal Uriel. "Determination of key device parameters for short- and long-channel Schottky-type carbon nanotube field-effect transistors." TUD Press, 2018. https://tud.qucosa.de/id/qucosa%3A38272.
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The Schottky barrier, contact resistance and carrier mobility in carbon nanotube (CNT) field-effect transistors (FETs) are discussed in detail in this thesis. Novel extraction methods and definitions are proposed for these parameters. A technology comparison with other emerging transistor technologies and a performance projection study are also presented. A Schottky barrier height extraction method for CNTFETs considering one-dimensional (1D) conditions is developed. The methodology is applied to simulation and experimental data of CNTFETs feasible for manufacturing. Y-function-based methods (YFMs) have been applied to simulation and experimental data in order to extract a contact resistance for CNTFETs. Both extraction methods are more efficient and accurate than other conventional approaches. Practical mobility expressions are derived for CNTFETs covering the ballistic as well as the non-ballistic transport regime which enable a straightforward evaluation of the transport in CNTs. They have been applied to simulation and experimental data of devices with different channel lengths and Schottky barrier heights. A comparison of fabricated emerging transistors based on similar criteria for various application scenarios reveals CNTFETs as promising candidates to compete with Si-based technologies in low-power static and dynamic applications. A performance projection study is suggested for specific applications in terms of the studied design parameters.
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Jain, Payal. "On the Impact of Channel and Channel Quality Estimation on Adaptive Modulation." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/36072.
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The rapid growth in wireless communications has given rise to an increasing demand for channel capacity using limited bandwidth. Wireless channels vary over time due to fading and changing interference conditions. Typical wireless systems are designed by choosing a modulation scheme to meet worst case conditions and thus rely on power control to adapt to changing channel conditions. Adaptive modulation, however, exploits these channel variations to improve the spectral efficiency of wireless communications by intelligently changing the modulation scheme based on channel conditions. Necessarily, among the modulation schemes used are spectrally efficient modulation schemes such as quadrature amplitude modulation (QAM) techniques.
QAM yields the high spectral efficiency due to its use of amplitude as well as phase modulation and therefore is an effective technique for achieving high channel capacity. The main drawbacks of QAM modulation are its reduced energy efficiency (as compared to standard QPSK) and its sensitivity to channel amplitude variations. Adaptive modulation attempts to address the first drawback by using more energy efficient schemes in low SNR conditions are reserving the use of QAM for high SNR conditions. The second drawback leads to a requirement of high quality channel estimation. Many researchers have studied pilot symbol assisted modulation for compensating the effects of fading at the receiver. A main contribution of this thesis is the investigation of different channel estimation techniques (along with the effect of pilot symbol spacing and Doppler spread) on the performance of adaptive modulation.
Another important parameter affecting adaptive modulation is the signal-to-noise ratio. In order to adapt modulation efficiently, it is essential to have accurate knowledge of the channel signal-to-noise ratio. The performance of adaptive modulation depends directly on how well the channel SNR is estimated. The more accurate the estimation of the channel SNR is, the better the choice of modulation scheme becomes, and the better the ability to exploit the variations in the wireless channel is. The second main contribution
of this thesis is the investigation of the impact of SNR estimation techniques on the performance and spectral efficiency of adaptive modulation. Further, we investigate the impact of various channel conditions on SNR estimation and the resulting impact on the performance of adaptive modulation. Finally, we investigate long term SNR estimation, its use in adaptive modulation and present a comparison between the two approachesMaster of Science
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Savory, Daniel Chase. "Power Side-Channel DAC Implementations for Xilinx FPGAs." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4038.
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This thesis presents a novel power side-channel DAC (PS-DAC) which is constructed from user-controllable short circuits in FPGAs and which manipulate overall system power through dynamic power dissipation. Alternately, similar PS-DACs are created using shift-register primitives(SRL16E) which manipulate system power through switching logic, for means of comparison with short-circuit-based PS-DACs. PS-DACs are created of various sizes using both short-circuit-based and shift-register-based methods. These PS-DACs are characterized in terms of output linearity,monotonicity, and frequency distortion. Applications explored in this thesis which use PS-DAC technology include a Simple Power Analysis (SPA) side-channel transmitter, and a frequency watermarking application. These applications serve as proof-of-concept for PS-DAC use in sidechannel communication applications.
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Zaki, Tarek [Verfasser], and Joachim N. [Akademischer Betreuer] Burghartz. "Short-channel organic thin-film transistors : fabrication, characterization, modeling and circuit demonstration / Tarek Zaki. Betreuer: Joachim N. Burghartz." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2015. http://d-nb.info/1069290238/34.
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Sundararajan, Abhishek. "A STUDY ON ATOMICALLY THIN ULTRA SHORT CONDUCTING CHANNELS, BREAKDOWN, AND ENVIRONMENTAL EFFECTS." UKnowledge, 2015. http://uknowledge.uky.edu/physastron_etds/27.
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We have developed a novel method of producing ultra-short channel graphene field effect devices on SiO2 substrates and have studied their electrical transport properties. A nonlinear current behavior is observed coupled with a quasi-saturation effect. An analytical model is developed to explain this behavior using ballistic transport, where the charge carriers experience minimal scattering. We also observe multilevel resistive switching after the device is electrically stressed. In addition, we have studied the evolution of the electrical transport properties of few-layer graphene during electrical breakdown. We are able to significantly increase the time scale of break junction formation, and we are able to observe changes occurring close to breakdown regime. A decrease in conductivity along with p−type doping of the graphene channel is observed as the device is broken. The addition of structural defects generated by thermal stress caused by high current densities is attributed to the observed evolution of electrical properties during the process of breakdown. We have also studied the effects of the local environment on graphene devices. We encapsulate graphene with poly(methyl methacrylate) (PMMA) polymer and study the electrical transport through in situ measurements. We have observed an overall decrease in doping level after low-temperature annealing in dry-nitrogen, indicating that the solvent in the polymer plays an important role in doping. For few-layer encapsulated graphene devices, we observe stable n−doping. Applying the solvent onto encapsulated devices demonstrates enhanced hysteretic switching between p and n−doped states.
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Crowell, Kelly Jean Geography & Oceanography Australian Defence Force Academy UNSW. "Short wave infrared spectral response of fluvial channel sands in the Towamba River, NSW, Australia : implications for sediment tracing." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Geography and Oceanography, 2002. http://handle.unsw.edu.au/1959.4/38680.
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Emergent spatial signals which may be interpreted in the context of fluvial sediment transport processes are detected through the use of reflectance spectroscopy in the sand-sized sediments of the Towamba River, southeastern New South Wales. Reflectance spectroscopy of sufficiently fine spectral resolution represents a technique for mineral composition analysis which is complementary to X-ray diffraction, with advantages in terms of ease of sample preparation and rapidity of measurement. Instrumentation is available allowing high-quality spectrum acquisition in the field and from airborne and satellite-borne instruments. The former allows mineral analyses to more easily be incorporated into sediment tracing studies as an additional variable. The latter offers large scale, repeatable areal coverage of a dynamic system in which sediments are exposed to the sky. The Towamba River drains a catchment of c. 1000 km [square] in extensively altered granitic terrain along the south coast of New South Wales, and carries significant quantities of sand-sized sediment through much of the system. Pervasive but spatially variable chlorite, epidote, and sericite have been described in local and neighbouring terrain. These are spectrally active in the SWIR wavelength region in which the PIMA portable spectrometer operates. The airborne HyMap instrument is sensitive through this range as well as through the visible and near-infrared regions. Conventionally such channel sediments would represent a single class in the context of the broader landscape, and comparatively they represent a domain of restricted variance. In this study of samples of sediment were collected for analysis with the PIMA, the results of which supported the efficacy of such an exercise in a conventional tracing context and supported analysis of HyMap imagery. Although issues related to reduction of HyMap-detected radiance to reflectance prevented effective analysis of the shorter wavelengths sensitive to the presence of ferrous and ferric iron, the consideration of absorption feature depths and the application of a matched filtering operator revealed gross-scale spatial patterns which were interpreted as two populations of sand in the main channel. This interpretation is consistent with bank erosion occurring during two very large magnitude flow events in the 1970s, with minor ongoing perturbation of the sediment signal in the main channel by the contribution of sediment from tributaries. The presence of a definite spatial signal having been established, routes for further investigation are suggested. A noisy signal hypothesised on the basis of imagery may be used to better direct a field sampling program for a conventional sediment tracing study. The signal to noise ratio may be improved for example through calibration of radiance to reflectance and removal of atmospheric interference and improved field sampling schemes, after which more rigorous, quantitative exercises such as geostatistical ???field??? trial or spatial series analysis may be performed. Connections to process through sediment transport models are enabled through the use of GIS.
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Aboud, Maurice J. "The Development of Direct Ultra-Fast PCR for Forensic Genotyping Using Short Channel Microfluidic Systems With Enhanced Sieving Matrices." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/715.
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There are situations in which it is very important to quickly and positively identify an individual. Examples include suspects detained in the neighborhood of a bombing or terrorist incident, individuals detained attempting to enter or leave the country, and victims of mass disasters. Systems utilized for these purposes must be fast, portable, and easy to maintain. The goal of this project was to develop an ultra fast, direct PCR method for forensic genotyping of oral swabs.
The procedure developed eliminates the need for cellular digestion and extraction of the sample by performing those steps in the PCR tube itself. Then, special high-speed polymerases are added which are capable of amplifying a newly developed 7 loci multiplex in under 16 minutes. Following the amplification, a postage stamp sized microfluidic device equipped with specially designed entangled polymer separation matrix, yields a complete genotype in 80 seconds. The entire process is rapid and reliable, reducing the time from sample to genotype from 1-2 days to under 20 minutes. Operation requires minimal equipment and can be easily performed with a small high-speed thermal-cycler, reagents, and a microfluidic device with a laptop. The system was optimized and validated using a number of test parameters and a small test population. The overall precision was better than 0.17 bp and provided a power of discrimination greater than 1 in 106.
The small footprint, and ease of use will permit this system to be an effective tool to quickly screen and identify individuals detained at ports of entry, police stations and remote locations. The system is robust, portable and demonstrates to the forensic community a simple solution to the problem of rapid determination of genetic identity.
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Fathololoumi, Saeed. "Analysis of the Deep Sub-Micron a-Si:H Thin Film Transistors." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/928.
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The recent developments of high resolution flat panel imagers have prompted interests in fabricating smaller on-pixel transistors to obtain higher fill factor and faster speed. This thesis presents fabrication and modeling of short channel amorphous silicon (a-Si:H) vertical thin film transistors (VTFT). A variety of a-Si:H VTFTs with different channel lengths, from 100 nm to 1 μm, are successfully fabricated using the discussed processing steps. Different structural and electrical characteristics of the fabricated device are measured. The results of I-V and C-V characteristics are comprehensively discussed. The 100 nm channel length transistor performance is diverged from regular long channel TFT characteristics, as the short channel effects become dominant in the device, giving rise to necessity of having a physical model to explain such effects.
An above threshold model for a-Si:H VTFT current characteristics is extracted. The transport mechanisms are explained and simulated for amorphous silicon material to be used in the device model. The final model shows good agreement with experimental results. However, we used numerical simulation, run in Medici, to further verify the model validity. Simulation allows us to vary different device and material parameters in order to optimize fabrication process for VTFT. The capacitance behavior of the device is extensively studied alongside with a TFT breakdown discussion.
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Murali, Raghunath. "Scaling opportunities for bulk accumulation and inversion MOSFETs for gigascale integration." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/submitted/etd-02132004-173432/unrestricted/murali%5FRaghunath%5F405%5F.pdf.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2004.Hess, Dennis, Committee Member; Meindl, James, Committee Chair; Allen, Phillip, Committee Member; Cressler, John, Committee Member; Davis, Jeffrey, Committee Member. Vita. Includes bibliographical references (leaves 108-119).
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Park, Pil Sung. "Advanced Channel Engineering in III-Nitride HEMTs for High Frequency Performance." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1386015448.
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Wang, Qian. "Regulation of sodium transport across epithelia derived from human mammary gland." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17600.
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Doctor of PhilosophyDepartment of Anatomy and Physiology
Bruce D. Schultz
The first aim of this project is to define the cellular mechanisms that account for the low Na[superscript]+ concentration in human milk. MCF10A cells, which were derived from human mammary epithelium and grown on permeable supports, exhibit amiloride- and benzamil-sensitive short circuit current (I[subscript]sc), suggesting activity of the epithelial Na[superscript]+ channel, ENaC. When cultured in the presence of cholera toxin (Ctx), MCF10A cells exhibit greater amiloride sensitive I[subscript]sc at all time points tested, an effect that is not reduced with Ctx washout for 12 hours or by cytosolic pathways inhibitors. Ctx increases the abundance of both beta and gamma-ENaC in the apical membrane and increases its monoubiquitination but without changing total protein and mRNA levels. Additionally, Ctx increases the levels of both the phosphorylated and the nonphosphorylated forms of Nedd4-2, a ubiquitin-protein ligase that regulates ENaC degradation. The results reveal a novel mechanism in human mammary gland epithelia by which Ctx regulates ENaC-mediated Na[superscript]+ transport. The second project aim is to develop a protocol to isolate mammary gland epithelia for subsequent in vitro culture. Caprine (1[superscript]0CME) and bovine mammary epithelia (1[superscript]0BME) were isolated and cultured on permeable supports to study hormone- and neurotransmitter-sensitive ion transport. Both 1[superscript]0CME and 1[superscript]0BME cells were passed for multiple subcultures and all passages formed electrically tight barriers. 1[superscript]0CME were cultured in the presence of hydrocortisone and exhibited high electrical resistance and amiloride-sensitive I[subscript]sc, suggesting the presence of ENaC-mediated Na[superscript]+ transport. 1[superscript]0BME were grown in a complex media in the presence or absence of dexamethasone. In contrast to 1[superscript]0CME, 1[superscript]0BME exhibited no detectable amiloride-sensitive I[subscript]sc in either culture condition. However, 1[superscript]0BME monolayers responded to an adrenergic agonist, norepinephrine, and a cholinergic agonist, carbamylcholine, with rapid increases in I[subscript]sc. Thus, this protocol for isolation and primary cell culture can be used for future studies that focus on mammary epithelial cell regulation and functions. In conclusion, the results from these projects demonstrate that mammary epithelial cells form electrically tight monolayers and can exhibit neurotransmitter- and/or hormone-induced net ion transport. The mechanisms that regulate Na[superscript]+ transport across mammary gland may provide clues to prevent or treat mastitis.
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Pacheco-Sánchez, Aníbal Uriel [Verfasser], Michael [Gutachter] Schröter, and C. [Gutachter] Maneux. "Determination of key device parameters for short- and long-channel Schottky-type carbon nanotube field-effect transistors / Aníbal Uriel Pacheco-Sánchez ; Gutachter: Michael Schröter, C. Maneux." Dresden : TUD Press, 2020. http://d-nb.info/1227053703/34.
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Farrell, Hannah Lucia, and Hannah Lucia Farrell. "Reclamation Practices and Impacts of a Pipeline Corridor in Southern Arizona: Seeding and Vehicle Trampling Impact Vegetation Establishment: Construction Alters Short-term Ephemeral Channel Morphology Trends." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620633.
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Anthropogenic disturbances are increasing in arid lands, as are expectations to successfully minimize impacts to natural resources and reclaim sites to publicly acceptable levels. This research explores the effectiveness of reclamation practices on a 60 mile natural gas pipeline constructed in September of 2014 that spans from west of Tucson to the border of Mexico. First, a controlled field experiment was conducted to assess the effects of seeding, grazing, and trampling (vehicular, cattle, and human foot traffic) on the reclaimed pipeline Right-Of-Way (ROW). Vegetation establishment (native plant cover; undesirable plant cover; species richness; herbaceous biomass), soil movement, and plant functional group community development was compared among the treatments. Reclaimed ROW areas left to recover without seeding resulted in similar vegetation cover, species, and community composition as undisturbed desert areas, although the presence of undesirable species was greater. The combined impacts of grazing and trampling resulted in reduced vegetation establishment and increased soil erosion. Second, the impacts of the pipeline construction on ephemeral wash channels were analyzed in terms of channel morphology and riparian vegetation changes. Channel cross section dimensions were measured upstream of the ROW, downstream of the ROW, and within the ROW before and after the 2015 Monsoon season to evaluate impacts on channel morphology and erosion processes. High resolution aerial imagery taken before and after pipeline construction was used to evaluate changes in riparian vegetation cover. Reduced herbaceous vegetation cover downstream of the ROW was detected, which may have been the result of increased channel scour within the ROW and increased sediment deposition downstream of the ROW. This research improves our understanding of and may aid in selection of appropriate reclamation practices.
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David, Radu Alin. "Improving Channel Estimation and Tracking Performance in Distributed MIMO Communication Systems." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-dissertations/229.
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This dissertation develops and analyzes several techniques for improving channel estimation and tracking performance in distributed multi-input multi-output (D-MIMO) wireless communication systems. D-MIMO communication systems have been studied for the last decade and are known to offer the benefits of antenna arrays, e.g., improved range and data rates, to systems of single-antenna devices. D-MIMO communication systems are considered a promising technology for future wireless standards including advanced cellular communication systems. This dissertation considers problems related to channel estimation and tracking in D-MIMO communication systems and is focused on three related topics: (i) characterizing oscillator stability for nodes in D-MIMO systems, (ii) the development of an optimal unified tracking framework and a performance comparison to previously considered sub-optimal tracking approaches, and (iii) incorporating independent kinematics into dynamic channel models and using accelerometers to improve channel tracking performance. A key challenge of D-MIMO systems is estimating and tracking the time-varying channels present between each pair of nodes in the system. Even if the propagation channel between a pair of nodes is time-invariant, the independent local oscillators in each node cause the carrier phases and frequencies and the effective channels between the nodes to have random time-varying phase offsets. The first part of this dissertation considers the problem of characterizing the stability parameters of the oscillators used as references for the transmitted waveforms. Having good estimates of these parameters is critical to facilitate optimal tracking of the phase and frequency offsets. We develop a new method for estimating these oscillator stability parameters based on Allan deviation measurements and compare this method to several previously developed parameter estimation techniques based on innovation covariance whitening. The Allan deviation method is validated with both simulations and experimental data from low-precision and high-precision oscillators. The second part of this dissertation considers a D-MIMO scenario with $N_t$ transmitters and $N_r$ receivers. While there are $N_t imes N_r$ node-to-node pairwise channels in such a system, there are only $N_t + N_r$ independent oscillators. We develop a new unified tracking model where one Kalman filter jointly tracks all of the pairwise channels and compare the performance of unified tracking to previously developed suboptimal local tracking approaches where the channels are not jointly tracked. Numerical results show that unified tracking tends to provide similar beamforming performance to local tracking but can provide significantly better nullforming performance in some scenarios. The third part of this dissertation considers a scenario where the transmit nodes in a D-MIMO system have independent kinematics. In general, this makes the channel tracking problem more difficult since the independent kinematics make the D-MIMO channels less predictable. We develop dynamics models which incorporate the effects of acceleration on oscillator frequency and displacement on propagation time. The tracking performance of a system with conventional feedback is compared to a system with conventional feedback and local accelerometer measurements. Numerical results show that the tracking performance is significantly improved with local accelerometer measurements.
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SONG, HONG-ZHENG, and 宋弘政. "Short channel V groove field effect transistor." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/64331593727557706381.
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Chiou, Yuh-Wen, and 邱郁文. "Reliability Analysis of Short-Channel P-MOSFETs." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/55075540666724093170.
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碩士國立交通大學
電子工程學系
85
In this thesis , the parameter extraction of P-MOSFETs is made first before quantitatively analyzing on the degradation of short-channel P-MOSFETs. The charge-pumping method developed by Advanced Semiconductor Device Reasearch Laboratory has been used to profiling the distributions of the interface-state density and the oxide traps and the results are taken to explain the I-V characteristics. We concentrate our analysis on the reliability of buried-channel P-MOSFETs. When the fresh devices are measured by the charge-pumping method , some strange phenomenon has been discovered and is dramatically different from N-MOSFET*s. The surface-channel P-MOSFETs thus are measured for comparisons. We find that such a phenomenon only appears on counter-implanted buried-channel P-MOSFETs. The existence of the active-region defects due to counter-implant is the major reason to account for the distribution of interface-state density we measured. After stressing for a long time , the active-region defects appear the minor effects on the profiling of the interface-state density. Therefore , the results can be used to explain the I-V characteristics including the subthreshold characteristics , turn-on current and substrate current. Based on these analyses , we can improve the device design for high performance and reliability applications. In addition , the active-region defects measured by the charge-pumping method can also help us for the process improvement.
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LIN, ZAN-XI, and 林讚西. "A unified I-V model for short channel MOSFETs with implanted channel." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/85058718927802808353.
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XIE, SHI-ZHAO, and 謝式釗. "Computer simulations of short-channel counter-implanted P-channel MOSFET's CMOS/VLSI." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/17199223931701152851.
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李政宗. "An intrinsic capacitance model for short channel MOSFETs." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/41903037780377084758.
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Hsieh, Yu-En, and 謝於恩. "Analysis of short-channel power device breakdown voltage." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68808087731263493805.
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碩士國立勤益科技大學
電子工程系
101
Power device plays an important role in the development of technology. Everyday electronic device such as PCs, smartphones and power-saving LED always used Power devices. The design of the power device in this research can be used for devices that require 90nm and 130nm, which is suitable for consumer electronic products. It is also an important direction for the development of future power component design. In this paper, a small power component designed to explore the basis. First, the differences in aspect ratio of the STI produce different power components. Then the length of the narrow channel power components to produce 90nm power components, and comparative analysis of the different structure of the STI process breakdown voltage characteristics. However, due to the limit of current manufacturing technology and the voltage withstandability of the 130 nm power component, there is not a very well integrated production process. According to TSMC’s website, the 130 nm and 90 nm BCD technology is still under development. In this paper, first explore the next generation 90-nanometer technology issues in order to provide the future process improvements. In this paper, the design of the drift region and the STI design are consistent with the current semiconductor manufacturing technology. All processes used by national laboratories also modeled the machine parameters. So the simulation process, will be the development and design of components used. This paper also found that the industry can’t properly produce the main production. Channel length of 90 nm power components, production often because of the pressure can’t be controlled drift region and the gate oxide layer can withstand high pressure problem. In this paper, the breakdown voltage drift region and present its analysis of the problem.
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Shia, Ruei-Kai, and 夏瑞鍇. "Study of Short Recessed Channel Schottky Barrier MOSFETs." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/92204154405515488122.
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碩士元智大學
電機工程學系
99
This thesis explores the current transport and device scaling of the recessed channel dopant segregated Schottky barrier MOSFETs (RC DS SBMOS). It also discusses an asymmetric source/drain structure of the RC DS SBMOS device to demonstrate a high on-current and suppress short-channel effect. The use of the dopant segregation layer reduces the parasitic resistance, caused by the recessed channel, to have a higher on-current of the recessed channel Schottky barrier MOSFETs. The recessed channel structure has a separate source, channel and drain region. The separately isolated drain region relieves the penetration of drain-side electrical field to have a suppressed short-channel effect. A halo implant profile helps to improve the scalability of Schottky barrier MOSFETs further. The asymmetric drain recessed structure enhances the driving on-current, and simultaneously, minimizes the short-channel effect to have an optimized RC DS SBMOS device for the use in future CMOS applications.
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Chen, Ching-Ming, and 陳景明. "Computer simulation of short-buried-channel n-MOSFET's." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/56861137772290558150.
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碩士國立交通大學
電子研究所
81
In this thesis, the basic device physics of a buried chan- nel n-MOSFET are described, which include the threshold-volta- ge model and I-V characteristics. Based on these models, the extraction methods for the device parameters including the de- vice structure parameters and the material parameters are pre- sented. The device structure parameters include effective cha- nnel length, channel doping profile, and source/drain doping profile and its junction depth. The material parameters inclu- de the parameters in the mobility model. Using these extracted parameters, we can simulate the electrical characteristics of the fabricated buried channel n-MOSFET's by using a two-dimen- sional numerical MOSFET simulator ( SUMMOS ). It is shown that good agreements between simulation results and experimental data are obtained for wide ranges of applied biases and chann- el lengths. Based on the simulation, the drain-induced barrier loweri- ng and punch-through effects of short-buried-channel n-MOS- FET's are discussed, and the methods for improving these short-channel effects are proposed.
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Chang, Ting-Huan, and 張廷桓. "The Effective Channel Length and Source-Drain Series Resistance Extraction of Short Channel MOSFET." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/79240897943427255183.
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博士中正理工學院
國防科學研究所
86
Abstract A new technique of determining the effective channel length by directly measuring source-drain series resistance of metal-oxide-semiconductor field-effect transistors (MOSFETs) was proposed. By using MOSFETs with scaled gate lengths, the source- drain series resistance can be obtained from a egenerate?device whose source and drain regions are connected. The gate length and the total resistance of the degenerate MOSFET are the lower limits of channel length reduction and source-drain series- resistance, respectively. In order to determine whether a MOSFET source and drain are connected, a quantitative ifference of total resistance?(DTR) method, which can also be used to electrically determine the gate length of a normal MOSFET after the fabrication process, was developed in this study. Also, we proposed qualitative methods to judge whether a MOSFET is degenerate. The effective channel length can then be extracted from the obtained series resistance and I-V of MOSFETs. In this study, the final result of the determined channel length reduction DL is the metallurgical DLmet and the source-drain series resistance is not a constant but clearly showed gate bias dependency. This technique, although requires very short-gate-length devices, is not affected by source-drain series-resistance gate bias dependence issue encountered in conventional I-V methods. Moreover, because of the simplicity of this technique, it can be used in process monitoring, device design and SPICE modeling.
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Zhan, Shun-Cheng, and 詹舜丞. "Short-interval Mechanism and Platform Design for Auctioning Homogeneous Channel." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/35593997964547315248.
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碩士國立臺灣大學
電機工程學研究所
98
The theme of this thesis research is on the design of the short-interval secondary spectrum market mechanism and platform. We first assessed the future needs of new services for leasing spectrum channels/bands in a short-interval secondary spectrum market in, the availability of idle spectrum channels/bands, and the motivations for license holders to lease out channels. The participating players in the market include a Mobile Network Operator (MNO), Mobile Virtual Network Operators (MVNOs), and a spectrum broker. Although there are no spectrum brokers in the existing VoIP (Voice of Internet Protocol) spectrum trading market, we adopt a spectrum broker as an impartial third party in the short-interval spectrum market based on the concept of market efficient governance proposed by Williamson in 1986. Based on the characteristics of the short-interval secondary spectrum market, a single round, sealed bid auction is chosen for detailed design. It is aimed to allocate channels efficiently, and reflect the value of the channels according to the requirement of MVNOs. The spectrum broker is also the auctioneer who coordinates the auction procedure. In the auction, the auctioneer selects winning bids by solving the Knapsack problem that maximizes bid price combination. The winners settle the payment according to a second price scheme of multiple objects. In making bid offer decision, individual MVNOs estimate the number of demand channels based on their respective customer service demand. MVNOs calculate the channel values according to the expected revenue, running cost, expected profit rate and customer service dissatisfaction. Analyses of the auction model under different bidding attitude lead to the following findings: (1) MVNOs offering bids based on their true valuation of channels is the optimal bidding strategy. The spectrum broker thus allocates channels to MVNOs who value the channels most. (2) MVNOs bidding aggressively can win a higher percentage of supply channels than bidding conservatively. (3) The MNO needs to set the reserve price for the channels when the winner settlement rule is to pay the second price. (4) The second-price settlement rule suits an intensely competitive market We designed and implemented the auction mechanism on a short-interval spectrum auction (SISA) platform, which adopted Flash CS4 for interface design, MySQL 4.0.24 as the database, Apache 1.3.33 as the web server, and PHP for the server-side programming language. The SISA platform has modules of the auction mechanism, the MVNO bid decision model, and the spectrum broker bid selection model. In order to simulate the auction result or human decision, the platform also includes three MVNO bid decision modes: automatic, manual, and supervised.
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Hsieh, Wen Yi, and 謝文義. "A 2-D Analytic Model for Short-Channel SOI MOSFET." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/07709657787547765406.
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碩士國立交通大學
電子工程系
89
Recently, the SOI structure has drawn much attention for its advantages over bulk device such as perfect device isolation, elimination of latch-up path and improved radiation hardness. Moreover, a number of companies have announced that they will use the Silicon-on-Insulator (SOI) technology in commercial VLSI production. Therefore, it is expected that the SOI technology will become a mainstream technology. In this thesis, the basic physical characteristics and advantages of SOI MOSFET will be analyzed and discussed. This thesis focuses on the analytic model of the short-channel fully-depleted SOI MOSFET. Therefore, the analytic threshold voltage model and I-V model are derived for short-channel fully-depleted SOI MOSFET. With the help of a 2D numerical simulator (Medici), the accuracy of the analytic models of short-channel fully-depleted SOI MOSFET have been confirmed. Finally, some future researches deserved further efforts are summarized
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Huang, Fu-Tsung, and 黃富聰. "Finite State Markov Channel for Dedicated Short Range Communication(DSRC)." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/82279261987772701581.
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碩士國立臺灣海洋大學
通訊與導航工程系
97
The object of this study is to model a wireless fading channel by Jakes model and log-normal shadowing model. We assume the DSRC system channel can be modeled by Jakes model with log-normal shadowing. The DSRC system provides the transmission LOS (line of sight) of security information for vehicle of the movements and the NLOS (non-line of sight) provides wireless, real time, long distance and two-way communication. After analyzing the channels, we utilize the signal-to-noise ratio to partition the channel state in DSRC system, and described by finite-state Markov channels. We also discuss and compare the transition probability and the steady state probability of every state. After dividing the receiving the signal-to-noise ratio into finite space, it is able to use of finite-state Markov channels model to construct the wireless Rayleigh fading channels or other fading channels. These effective and reliable models can divide the signal-to-noise ratio of receiver and get useful system information to improve the functions of system effectively.
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Chen, Yu-Hsuan, and 陳祐萱. "Simulation and Design of Short-Channel Tunnel Field-Effect Transistors." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/14752116469409540235.
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碩士國立暨南國際大學
電機工程學系
103
Tunnel field-effect transistor (TFET) has demonstrated its steep subthreshold swing to surpass the physical limit of MOSFET devices, serving as a promising candidate for energy-efficient applications. However, scaling TFET devices into the sub-20 nm regimes suffers from the severe short-channel effects. This thesis elucidates the physical mechanisms of the short-channel effects in conventional TFET devices, and explores the proper design of sub-10 nm TFETs using asymmetric junctionless structure. Two-dimensional device simulations are performed to examine the on-off switching of TFET devices incorporated with appropriate physical models. By employing the proposed asymmetric junctionless architecture, the TFET devices can be successfully scaled down into sub-10 nm regimes to follow the scaling pace for future low-power applications.
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Joseph, Thomas. "Theoretical Study of Short Channel Effects in Planar Bulk nMOS." 2018. https://monarch.qucosa.de/id/qucosa%3A21283.
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Scaling has been pivotal in the success of the Moore's law. Using scaling techniques to improve the MOSFET comes at a risk of growing short channel effects. This publication deals with the theoretical study of impact of gate length scaling on planar bulk MOSFET. A systematical study shows that the impact of short channel effects like drain induced barrier lowering, subthreshold leakage, hot carrier generation and channel length modulation grows with gate length scaling. Thereby degrading the MOSFET performance. In addition to the numerical device simulation an analytical modelling of the device is also performed. Though the analytical model explains the device characteristic trends, it is found to be quantitative inaccurate in comparison to the numerical model especially when scaling below deep sub-micrometer regime.
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ZHOU, SHENG-XIONG, and 周勝雄. "The breakdown behavior of short-channel CMOS devices under AC operations." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/82689839130949815527.
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Shih, Chun-Hsing, and 施君興. "Device Design and Modeling of Short-Channel Effect for Nanoscale MOSFET." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/55516698564296198206.
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博士國立清華大學
電機工程學系
92
The objective of this dissertation is to explore in depth the feasibility of continued scaling for the nanoscale MOSFET devices through precise modeling of short-channel effect and proper design of channel profile and device structure. The analytical short-channel effect models without any fitting parameter have been successfully derived for nanoscale MOSFETs from analytical solutions of 2D Poisson''s equation, including the sophisticated device structures such as ultra-shallow and graded source/drain junctions, and nonuniform retrograde and halo-doped channels. Detailed investigations and comparisons on short-channel effect are performed for wide ranges of device dimensions and technologies along with 2D numerical device simulations. The design considerations of channel profile and device structure are investigated for the optimization of short-channel effect and drain leakage current for nanoscale MOSFET devices. By using fully CMOS-compatible process, a novel Insulated Shallow Extension (ISE) is proposed for achieving sub-50 nm bulk MOSFETs. A design strategy of channel profile by using localized halo is also proposed for this new ISE structure. By combining this ISE structure with localized halo, sub-50 nm bulk MOSFET devices can be easily achieved with small threshold voltage roll-off, low drain leakage current, and suitable threshold voltage level. The short-channel effect models for nanoscale MOSFETs have been derived by using the effective-doping model. By viewing the MOSFET as distributed MOS capacitors in series, the short-channel threshold voltage is simply equal to the highest threshold voltage among them, that is the one with the highest distributed effective-doping concentration. The effective-doping model has the advantage of its capability in retaining the physical insight of the short-channel effect and incorporating 2D analytical solutions of Poisson''s equation. The scale-length approach for solving 2D Poisson''s equation is successfully extended to find the channel potential of MOSFET with nonuniform channels and various junction profiles. Based on the superposition principle and variable-separation method, this scale-length solution can give an excellent representation of the channel potential in the neighborhood of maximum potential barrier. Excellent agreements between the numerical simulated results and these short-channel effect models have been obtained for wide ranges of device dimensions and technologies. This model can lead to better understanding of the scaling limits and the impact of various device parameters on the short-channel effect. Since no empirical fitting parameters are involved in the derivations, it should be very helpful for the analysis and design of next generation bulk CMOS devices. The sophisticated design considerations of channel profile and device structure are one of the key challenges in developing the state-of-the-art nanoscale technology. The design strategy of channel profile is very important for achieving the sub-50 nm bulk CMOS devices. With the optimal choice of the location of heavy doped halo, it can be simultaneously accomplished to improve the roll-off of threshold voltage and to relieve drain band-to-band leakage current without raising the low threshold voltage. The adequate halo-to-extension spacing is the most effective design parameter to control the band-to-band leakage current and the threshold voltage roll-off. Instead of P-N junction, a sidewall dielectric oxide of proposed ISE structure is used to define the shallow extension to provide the precise control of the halo-to-extension spacing to achieve a sub-50 nm bulk MOSFET successfully. The combination of ISE with localized halo results in excellent short-channel behavior. It shows excellent performance on the short-channel behavior over the conventional bulk devices and serves a promising alternative of bulk MOSFET in sub-50 nm regime.