Download or read book Analytical Model and Numerical Simulation for the Transconductance and Drain Conductance of GaAs MESFETs written by Saadeddine Khemissi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation written by Mykhaylo Andriychuk and published by BoD – Books on Demand. This book was released on 2012-09-19 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical Simulation - from Theory to Industry is the edited book containing 25 chapters and divided into four parts. Part 1 is devoted to the background and novel advances of numerical simulation; second part contains simulation applications in the macro- and micro-electrodynamics. Part 3 includes contributions related to fluid dynamics in the natural environment and scientific applications; the last, fourth part is dedicated to simulation in the industrial areas, such as power engineering, metallurgy and building. Recent numerical techniques, as well as software the most accurate and advanced in treating the physical phenomena, are applied in order to explain the investigated processes in terms of numbers. Since the numerical simulation plays a key role in both theoretical and industrial research, this book related to simulation of many physical processes, will be useful for the pure research scientists, applied mathematicians, industrial engineers, and post-graduate students.
Download or read book Analysis and Modeling of GaAs MESFET s for Linear Integrated Circuit Design written by Mankoo Lee and published by . This book was released on 1990 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: A complete Gallium Arsenide Metal Semiconconductor Field Effect Transistor (GaAs MESFET) model including deep-level trap effects has been developed, which is far more accurate than previous equivalent circuit models, for high-speed applications in linear integrated circuit design. A new self-backgating GaAs MESFET model, which can simulate low frequency anomalies, is presented by including deep-level trap effects which cause transconductance reduction and the output conductance and the saturation drain current to increase with the applied signal frequency. This model has been incorporated into PSPICE and includes a time dependent I-V curve model, a capacitance model, a subthreshold current model, an RC network describing the effective substrate-induced capacitance and resistance, and a switching resistance providing device symmetry. An analytical approach is used to derive capacitances which depend on Vgs and Vds and is one which also includes the channel/substrate junction modulation by the self backgating effect. A subthreshold current model is analytically derived by the mobile charge density from the parabolic potential distribution in the cut-off region. Sparameter errors between previous models and measured data in conventional GaAs MESFET's have been reduced by including a transit time delay in the transconductances, gm and gds, by the second order Bessel polynomial approximation. As a convenient extraction method, a new circuit configuration is also proposed for extracting simulated S-parameters which accurately predict measured data. Also, a large-signal GaAs MESFET model for performing nonlinear microwave circuit simulations is described. As a linear IC design vehicle for demonstrating the utility of the model, a 3-stage GaAs operational amplifier has been designed and also has been fabricated with results of a 35 dB open-loop gain at high frequencies and a 4 GHz gain bandwidth product by a conventional half micron MESFET technology. Using this new model, the low frequency anomalies of the GaAs amplifier such as a gain roll-off, a phase notch, and an output current lag are more accurately predicted than with any other previous model. This new self-backgating GaAs MESFET model, which provides accurate voltage dependent capacitances, frequency dependent output conductance, and transit time delay dependent transconductances, can be used to simulate low frequency effects in GaAs linear integrated circuit design.
Download or read book Semiconductor Device Modelling written by Christopher M. Snowden and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 267 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor device modelling has developed in recent years from being solely the domain of device physicists to span broader technological disciplines involved in device and electronic circuit design and develop ment. The rapid emergence of very high speed, high density integrated circuit technology and the drive towards high speed communications has meant that extremely small-scale device structures are used in contempor ary designs. The characterisation and analysis of these devices can no longer be satisfied by electrical measurements alone. Traditional equivalent circuit models and closed-form analytical models cannot always provide consis tently accurate results for all modes of operation of these very small devices. Furthermore, the highly competitive nature of the semiconductor industry has led to the need to minimise development costs and lead-time associated with introducing new designs. This has meant that there has been a greater demand for models capable of increasing our understanding of how these devices operate and capable of predicting accurate quantitative results. The desire to move towards computer aided design and expert systems has reinforced the need for models capable of representing device operation under DC, small-signal, large-signal and high frequency operation. It is also desirable to relate the physical structure of the device to the electrical performance. This demand for better models has led to the introduction of improved equivalent circuit models and a upsurge in interest in using physical models.
Download or read book Characterization Modeling and Circuit Design of GaAs MESFET written by Kang Woo Lee and published by . This book was released on 1984 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two Dimensional Numerical Simulation of a Non isothermal GaAs MESFET written by Angela A. Lin and published by . This book was released on 1992 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: The low thermal conductivity of gallium arsenide compared to silicon results in self-heating effects in GaAs MESFETs that limit the electrical performance of such devices for high power applications. To date, analytical thermal models of self heating in GaAs MESFETs are based on the assumption of a uniformly heated channel. This thesis presents a two dimensional analysis of the electrothermal effect of this device based on the two dimensional power density distribution in the channel under various bias conditions. The numerical simulation is performed using the finite difference technique. The results of the simulation of an isothermal MESFET without heat effects is compared with various one dimensional analytical models in the literature. Electro thermal effects into the two-dimensional isothermal MESFET model allowed close examination of the temperature profile within the MESFET. The large gradient in power distribution results in a localized heat source within the channel which increases the overall channel temperature, which shows that the assumption of a uniformly heated channel is erroneous, and may lead to an underestimation of the maximum channel temperature.
Download or read book Gallium Arsenide and Related Compounds 1993 Proceedings of the 20th INT Symposium 29 August 2 September 1993 Freiburg im Braunschweig Germany written by Günter Weimann and published by CRC Press. This book was released on 1994-01-01 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gallium Arsenide and Related Compounds 1993 covers III-V compounds from crystal growth of materials to their device applications. Focusing on the fields of optical communications and satellite broadcasting, the book describes the practical applications for GaAs and III-V compounds in devices and circuits, both conventional and those based on quantum effects. It also discusses ultrafast GaAs transistors and integrated circuits, novel laser diodes, and tunneling devices, and considers the direction for future technologies. In addition, this volume addresses the increasing demands of ultra high speed systems that require careful selection of III-V materials to optimize the performance of electronic and optoelectronic components. It is ideal reading for physicists, materials scientists, electrical, and electronics engineers investigating III-V compound materials, properties, and devices.
Download or read book Effects of Hot carrier Phenomena on Performance of MESFET s written by Toshimi Wada and published by . This book was released on 1979 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization and Numerical Analysis of the Modulation Doped Heterojunction MESFET written by Christopher Frank Codella and published by . This book was released on 1984 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comprehensive Model of Frequency Dispersion of Gallium Nitride MESFET written by Rumman Raihan and published by . This book was released on 2018 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: A physics based analytical modeling for Gallium Nitride (GaN) MESFET has been developed in this project to calculate drain to source current versus drain to source voltage and the transconductance with and without traps centers using MATLAB software. The drain-bias dependence of trapped carrier concentration has been calculated and incorporated in drain current and transconductance to study the traps behavior on drain current and transconductance. The drain current has been developed by two sets of equations for non-saturation and saturation current components and two current equations have been merged by optimizing different physical parameters. Hence, the current clearly shows linear and non-linear properties to validate the device performance. The transconductance has been derived from the derivative of saturated drain current function to gate-source voltage for constant drain-source voltage. The threshold voltage has been determined from the gate-source voltage, when the transconductance is equal to zero. The transconductance has been also determined for various active channel thicknesses, which reflects the device frequency performance.
Download or read book Analytical Model of Gallium Nitride Metal Semiconductor Field effect Transistors written by Uttam Raj Sali and published by . This book was released on 2014 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project presents an analytical model of Gallium Nitride (GaN) MESFETs (metal-semiconductor field effect transistors). There are two band structures modeled for GaN: a Zinc Blende crystal structure and a Wurtzite crystal structure. This model is based on the parameters chosen for the Wurtzite crystal structure. The channel conductance, saturation current, transconductance, charge under the gate, drain-to-gate and gate-to-source capacitance, cutoff frequency, characteristic switching time, power-delay product, and breakdown voltage are calculated in the analysis of this model. These results are verified by two-dimensional computer calculations that agree with the results of the computer analysis and experimental data for a 1-æm gate GaN MESFET. A stray gate-to-drain and gate-to-source capacitance defined a limitation on the gate length as greater than 0.1 æm for a GaN MESFET. In this project, computer analysis is compared with experimental data for GaN. A MATLAB tool is used to obtain the computer analysis. The simulation shows computer analysis for GaN in agreement with the experimental data for a GaN MESFET.
Download or read book Compound Semiconductor Device Modelling written by Christopher M. Snowden and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at microwave, millimetre and optical frequencies. The apparent complexity of equivalent circuit and physics-based models distinguishes high frequency devices from their low frequency counterparts . . Over the past twenty years a wide range of modelling techniques have emerged suitable for describing the operation of compound semiconductor devices. This book brings together for the first time the most popular techniques in everyday use by engineers and scientists. The book specifically addresses the requirements and techniques suitable for modelling GaAs, InP. ternary and quaternary semiconductor devices found in modern technology.
Download or read book Modeling of Gallium Nitride MESFETs at High Temperatures written by FNU Syed Zabiullah and published by . This book was released on 2015 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: GaN shows an extreme promising material showing the properties of wide bandgap, high electron velocity and high breakdown voltage with low thermal generation rate, excellent thermal conductivity and high radiation resistance for high power and high frequency amplifier. An analytical model of GaN MESFET has been developed to simulate the temperature dependent drain current and transconductance. The drain current shows small variation in the current due the temperature transition from 300 K to 500 K. The transconductance also exhibits very insignificant change due to temperature variation from 300 K to 500 K. In order to understand the device performance at 300 K, the drain current has been computed for different gate-source voltage. The drain current clearly shows the linearity regime, non-linear regime and saturation regime to justify the validity of the model. Further, the drain current has been evaluated for different active channel thickness to justify the desired pinch-off voltage. The computed results show that GaN MESFET shows incredible thermal stability at extreme high temperatures.
Download or read book Analytical Model of GaAs MESFET Output Conductance with Frequency and Temperature Dependent Parameters written by Steven C. F. Lam and published by . This book was released on 1988 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The output characteristics of a conventional GaAs depletion-mode MESFET device have been investigated. One of the important parameters of the small-signal GaAs MESFET model, g[subscript ds] (output conductance), is shown to be frequency and temperature dependent. Variations in g[subscript ds] are a serious problem in many analog and digital circuits since gain and propagation delay are strong functions of g[subscript ds]. An analytical model which incorporates frequency and temperature dependent parameters has been developed and gives satisfactory results as compared with experimental data.
Download or read book An Improved Analytical Model of 4H SiC MESFET for Designing the Device for High Frequency and High power Applications written by Janet Arikian and published by . This book was released on 2021 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon Carbide is capable of delivering superior physical characteristics under cavil circumstances because of its inherent broad band gap, high critical breakdown field, high thermal conductivity, and high electron situation drift velocity. Due to its superior quality of high power and low loss, 4H-SiC MESFETs are gradually implemented in designing for High frequency and high power, new energy vehicle and locomotive traction, and so on. In this report, an analytical model is developed to evaluate and analyze many device electrical properties, such as I-V characteristics, transconductance including threshold d voltage, gate-to-source, and gate-to-drain capacitances, and specific-on resistance and cutoff frequency. Meanwhile, it presents more approaches to study how the variation of fabrication parameters such as doping energy level and ion dose density impacts the power and frequency performance for 4H-SiC based MESFETs devices. The model has been analyzed to study I-V characteristics, internal gate capacitances (Gate-to-source and gate-to-drain capacitances), transconductance, specific-on resistance, and cutoff-frequency simulation and analysis. The drain-to-source current reveals its variety along with the change of gate-to-source voltages, which goes up to 70A. Secondly, the ion dose intensity Q significantly affects the internal gate capacitances, which is valuable for evaluating the submicron MESFETS gate model performance under a typical fabrication setup. In addition, transconductance simulation results are obtained by the variation with disparate ion dose densities, which is agreeing well with published theoretical and experimental results. Besides, along with the gradual increase of N-drift layer concentration density, the specific-on resistance has reached to a value of 70ohm. μm2which is very promising property of power device. Lastly, the cutoff and maximum frequencies are 14 GHz and 35 GHz, respectively, with the development of fabrication to implement smaller gate length, if the gate length would be available to narrow down to blow 0.5μm, it has the potential to breakthrough 100 GHz to implement the super high-frequency application, which is also observed from the simulation results.
Download or read book Physics Based Analytical Model of the Frequency Behaviour of 4H SiC MESFET written by Ravi Teja Reddy Garugu and published by . This book was released on 2018 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: A physics based analytical modeling of SiC MESFET has been presented in this grad thesis to evaluate I-V characteristics, and transconductance under traps effects. The impact of grad thesis is to show the traps effects on different electrical parameter because the SiC material is still having adequate defects during growth, which promotes the trap center to degrade the device performance. The traps centers have been considered with different electronic capture cross-section in traps energy level. The drain currents for various gate-source voltage shows significant effect due traps effects, However, I-V characteristics shows a sharp view of linear and non-linear behavior of drain current, which shows no significant effects on switching properties due to the influence of trap centers. Similarly, the transconductance shows significant effect due to traps. The transconductance has been determined for different active channel thickness to study the device performance for power aided efficiency.
