Adelmo Ortiz-conde - Academia.edu (original) (raw)
Adelmo Ortiz-Conde was born in Caracas, Venezuela, on November 28, 1956. He received the professional Electronics Engineer degree from Universidad Simón Bolívar (USB), Caracas, Venezuela, in 1979 and the M.E. and Ph.D. from the University of Florida, Gainesville, in 1982 and 1985, respectively. His doctoral research, under the guidance of Prof. J. G. Fossum, was on the Effects of Grain Boundaries in SOI MOSFET’s. From 1979 to 1980, he served as an instructor in the Electronics Department at USB. In 1985, he joined the technical Staff of Bell Laboratories, Reading, PA, where he was engaged in the development of high voltage integrated circuits. Since 1987 he returned to the Electronics Department at USB where he was promoted to Full Professor in 1995. He was on sabbatical leave at Florida International University (FIU), Miami, from September to December 1993, and at University of Central Florida (UCF), Orlando, from January to August 1994, and again from July to December 1998. He also was on sabbatical leave at “Centro de Investigaciones y Estudios Avanzados” (CINVESTAV) National Polytechnic Institute (IPN), Mexico City, Mexico, from October 2000 to February 2001. He has coauthored one textbook, Analysis and Design of MOSFETs: Modeling, Simulation and Parameter Extraction (2012 Springer reprint of the original 1st ed. 1998, http://dx.doi.org/10.1007/978-1-4615-5415-8 ), over 160 international technical journal and conference articles (including 15 invited review articles). His present research interests include the modeling and parameter extraction of semiconductor devices.Dr. Ortiz-Conde is an EDS Distinguished Lecturer and the Chair of IEEE’s CAS/ED Venezuelan Chapter. He is editor of IEEE Electron Device Letters in the area of Silicon Devices and Technology. He was the Region 9 Editor of IEEE EDS Newsletter from 2000 to 2005. He is a Member of the Editorial Advisory Board of various technical journals: Microelectronics and Reliability, “Universidad Ciencia y Tecnología” and “Revista Ingeniería UC”. He regularly serves as reviewer of several international journals and he was the General Chairperson of the first IEEE International Caribbean Conference on Devices, Circuits, and Systems (ICCDCS) in 1995, Technical Chairperson of the second, fourth and fifth editions of this conference in 1998, 2002 and 2004 respectively, and the Chairperson of the Steering Committee in 2000.
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Papers by Adelmo Ortiz-conde
IEEE Transactions on Electron Devices, 2016
A new procedure to extract the parameters of mathematical models that describe charge flow phenom... more A new procedure to extract the parameters of mathematical models that describe charge flow phenomena through thin dielectrics is proposed for characterizing undesirable leakage current mechanisms in modern MOSFETs' gates. The procedure's basis is the small signal conductance-to-current ratio of the I-V characteristics. It is an alternative to, and has advantages over, the other presently used methods that extract those models' parameters from the slope and intercept of phenomenon-specific linear plots. In contrast, this is a generic method that may be directly applied to the I-V characteristics, regardless of the specific leakage mechanism involved. The procedure inherently reduces by one the number of unknowns that needs to be determined during numerical optimization. In addition, it does not require, as other traditional methods do, a prior knowledge of the exact relationship between the applied voltage and the effective internal electric field strength, which in this case is determined together with the other parameters. The procedure is illustrated by three examples with different kinds of data: mathematically synthesized, Computer Aided Design simulated, and experimentally measured leakage I-V characteristics of MOS capacitors.
IEEE Transactions on Electron Devices, 2016
Extrinsic parasitic series resistance and mobility degradation are two important parameters limit... more Extrinsic parasitic series resistance and mobility degradation are two important parameters limiting the performance of multifinger microwave MOSFETs. In this paper, we present a method to extract these parameters from measured drain-voltage versus gate-voltage characteristics at given constant values of drain current. Measured data of multifinger microwave MOSFETs are used to test and verify the developed method. The method requires only simple dc measurements on a single test device.
IEEE Transactions on Electron Devices, 2018
Transactions on Electrical and Electronic Materials, 2020
A novel method for the parameter extraction of thin-film transistors in weak-conduction and triod... more A novel method for the parameter extraction of thin-film transistors in weak-conduction and triode-region is presented. The parameter extraction is performed using two different and consistent functions based on the integration of experimental output characteristic. The method was tested using measured data of polycrystalline silicon (poly-Si) thin-film transistors (TFTs) and the results were compared with previously reported conventional methods.
2021 5th IEEE Electron Devices Technology & Manufacturing Conference (EDTM), 2021
The performance of MOSFETs is limited by the presence of parasitic series resistances. This artic... more The performance of MOSFETs is limited by the presence of parasitic series resistances. This article reviews three recent extraction methods to determine the values of drain and source series resistances from the measured drain current of a single three-terminal transistor. These methods can also be used in four-terminal MOSFETs.
Facta universitatis - series: Electronics and Energetics, 2017
This article reviews and appraises the dc lumped-parameter equivalent circuit models that have be... more This article reviews and appraises the dc lumped-parameter equivalent circuit models that have been proposed so far for representing some types of solar cells that can exhibit under certain circumstances a detrimental S-shaped concave deformation within the energy-producing fourth quadrant of their illuminated I-V characteristics. We first present a very succinct recollection of lumped-parameter equivalent circuits that are commonly used to model conventional solar cells in general. We then chronologically present and discuss lumped-parameter equivalent sub-circuits that, combined with conventional solar cell equivalent circuits, are used to specifically represent the undesired S-shaped behaviour. The mathematically descriptive equations of each complete equivalent circuit are also examined, and closed form solutions for the terminal current and voltage as explicit functions of each other are presented and discussed whenever available. While comparing the most salient features and e...
Solid-State Electronics, 2006
Solid-State Electronics, 2005
Solar Energy Materials and Solar Cells, 2006
Microelectronics Reliability, 2011
An alternative explicit multi-exponential model is proposed to describe multiple, arbitrary ideal... more An alternative explicit multi-exponential model is proposed to describe multiple, arbitrary ideality factor, conduction mechanisms in semiconductor junctions with parasitic series and shunt resistances. This Lambert function based model allows the terminal current to be expressed as an explicit analytical function of the applied terminal voltage, in contrast to the implicit-type conventional multi-exponential model. As a result this model inherently
Facta universitatis - series: Electronics and Energetics, 2014
This article presents an up-to-date review of several methods used for extraction of diode and so... more This article presents an up-to-date review of several methods used for extraction of diode and solar cell model parameters. In order to facilitate the choice of the most appropriate method for the given particular application, the methods are classified according to their lumped parameter equivalent circuit model: single-exponential, double-exponential, multiple-exponential, with and without series and parallel resistances. In general, methods based on numerical integration or optimization are recommended to reduce the possible uncertainties arising from measurement noise.
IEEE Sensors Journal
Large-area compatible, solar-blind deep-ultraviolet sensors based on active pixels are demonstrat... more Large-area compatible, solar-blind deep-ultraviolet sensors based on active pixels are demonstrated with CMOS amplifiers based on poly-Si thin-film transistors and Ga2 O3 thin-film photoresistors. The active pixel configuration sensor enables approximately 40X higher responsivity compared to a discrete sensor, and the CMOS inverter amplifier exhibits a gain of 210 V/V. The Ga2 O3-based sensors were integrated on the same substrate depositing the films using magnetron sputtering at room temperature, ensuring its compatibility with large-area applications. The responsivity of discrete Ga2 O3 sensors was evaluated at different wavelengths in the deep-ultraviolet and visible ranges, and showed a maximum responsivity of 51 A/W for a wavelength of 232 nm, with a deep-ultraviolet to visible light rejection ratio of approximately 102. The active pixel sensor was implemented as flame detector resulting in an output voltage signal of up to 2 V when the system was exposed to a flame under regular background illumination conditions.
Resumen es: Se presenta un procedimiento para convertir bidireccionalmente entre dos modelos para... more Resumen es: Se presenta un procedimiento para convertir bidireccionalmente entre dos modelos para la corriente de saturacion de transistores de pelicula delgada. Con...
The first part of this article presents the modeling of the long-channel bulk MOSFET as a particu... more The first part of this article presents the modeling of the long-channel bulk MOSFET as a particular case of the SOI MOSFET. The second part reviews compares and scrutinizes various methods to extract the threshold voltage, the effective channel and the individual values of drain and source resistances. These are important device parameters for modeling and circuit simulation.
Microelectronics Reliability, 2017
The performance of modern MOSFETs is limited by the presence of parasitic series resistances and ... more The performance of modern MOSFETs is limited by the presence of parasitic series resistances and mobility degradation. This article reviews and assesses 18 of the extraction methods currently used to determine the values of parasitic series resistances and mobility degradation from the measured drain current. The methods are separated in 3 groups: seven different methods that use the transfer characteristics of several devices having different mask channel lengths; five methods based on a single device with different drain and gate bias; six methods which account for the asymmetry between drain and source resistance.
IEEE Transactions on Electron Devices, 2015
— We propose a novel systematic procedure to individually characterize relevant physical phenomen... more — We propose a novel systematic procedure to individually characterize relevant physical phenomena that typify tunnel FETs (TFETs) in general. The procedure uses the Lambert W function to explicitly solve the subthreshold and above-threshold transfer characteristics of TFETs, as described by a recently proposed universal TFET compact model based on Kane's tunneling formulation. The resulting explicit analytic solutions may be used to numerically calculate, and thus to reveal, the terminal voltage-dependent functionalities of the device's subthreshold current swing and effective electric field. The description of the output characteristics' gate-to-source voltage dependence and saturation is also part of the procedure. The resulting functional representations of the relevant features constitute useful tools for basic device analysis and design, as well as for formulating specific mathematical descriptive models of these features. Atomistic, quantum-mechanical simulated data of an InAs homojunction TFET are used as an example to numerically and graphically illustrate the proposed characterization procedure.
This article reviews and appraises the dc lumped-parameter equivalent circuit models that have be... more This article reviews and appraises the dc lumped-parameter equivalent circuit models that have been proposed so far for representing some types of solar cells that can exhibit under certain circumstances a detrimental S-shaped concave deformation within the energy-producing fourth quadrant of their illuminated I–V characteristics. We first present a very succinct recollection of lumped-parameter equivalent circuits that are commonly used to model conventional solar cells in general. We then chronologically present and discuss lumped-parameter equivalent sub-circuits that, combined with conventional solar cell equivalent circuits, are used to specifically represent the undesired S-shaped behaviour. The mathematically descriptive equations of each complete equivalent circuit are also examined, and closed form solutions for the terminal current and voltage as explicit functions of each other are presented and discussed whenever available. While comparing the most salient features and e...
IEEE Transactions on Electron Devices, 2016
A new procedure to extract the parameters of mathematical models that describe charge flow phenom... more A new procedure to extract the parameters of mathematical models that describe charge flow phenomena through thin dielectrics is proposed for characterizing undesirable leakage current mechanisms in modern MOSFETs' gates. The procedure's basis is the small signal conductance-to-current ratio of the I-V characteristics. It is an alternative to, and has advantages over, the other presently used methods that extract those models' parameters from the slope and intercept of phenomenon-specific linear plots. In contrast, this is a generic method that may be directly applied to the I-V characteristics, regardless of the specific leakage mechanism involved. The procedure inherently reduces by one the number of unknowns that needs to be determined during numerical optimization. In addition, it does not require, as other traditional methods do, a prior knowledge of the exact relationship between the applied voltage and the effective internal electric field strength, which in this case is determined together with the other parameters. The procedure is illustrated by three examples with different kinds of data: mathematically synthesized, Computer Aided Design simulated, and experimentally measured leakage I-V characteristics of MOS capacitors.
IEEE Transactions on Electron Devices, 2016
Extrinsic parasitic series resistance and mobility degradation are two important parameters limit... more Extrinsic parasitic series resistance and mobility degradation are two important parameters limiting the performance of multifinger microwave MOSFETs. In this paper, we present a method to extract these parameters from measured drain-voltage versus gate-voltage characteristics at given constant values of drain current. Measured data of multifinger microwave MOSFETs are used to test and verify the developed method. The method requires only simple dc measurements on a single test device.
IEEE Transactions on Electron Devices, 2018
Transactions on Electrical and Electronic Materials, 2020
A novel method for the parameter extraction of thin-film transistors in weak-conduction and triod... more A novel method for the parameter extraction of thin-film transistors in weak-conduction and triode-region is presented. The parameter extraction is performed using two different and consistent functions based on the integration of experimental output characteristic. The method was tested using measured data of polycrystalline silicon (poly-Si) thin-film transistors (TFTs) and the results were compared with previously reported conventional methods.
2021 5th IEEE Electron Devices Technology & Manufacturing Conference (EDTM), 2021
The performance of MOSFETs is limited by the presence of parasitic series resistances. This artic... more The performance of MOSFETs is limited by the presence of parasitic series resistances. This article reviews three recent extraction methods to determine the values of drain and source series resistances from the measured drain current of a single three-terminal transistor. These methods can also be used in four-terminal MOSFETs.
Facta universitatis - series: Electronics and Energetics, 2017
This article reviews and appraises the dc lumped-parameter equivalent circuit models that have be... more This article reviews and appraises the dc lumped-parameter equivalent circuit models that have been proposed so far for representing some types of solar cells that can exhibit under certain circumstances a detrimental S-shaped concave deformation within the energy-producing fourth quadrant of their illuminated I-V characteristics. We first present a very succinct recollection of lumped-parameter equivalent circuits that are commonly used to model conventional solar cells in general. We then chronologically present and discuss lumped-parameter equivalent sub-circuits that, combined with conventional solar cell equivalent circuits, are used to specifically represent the undesired S-shaped behaviour. The mathematically descriptive equations of each complete equivalent circuit are also examined, and closed form solutions for the terminal current and voltage as explicit functions of each other are presented and discussed whenever available. While comparing the most salient features and e...
Solid-State Electronics, 2006
Solid-State Electronics, 2005
Solar Energy Materials and Solar Cells, 2006
Microelectronics Reliability, 2011
An alternative explicit multi-exponential model is proposed to describe multiple, arbitrary ideal... more An alternative explicit multi-exponential model is proposed to describe multiple, arbitrary ideality factor, conduction mechanisms in semiconductor junctions with parasitic series and shunt resistances. This Lambert function based model allows the terminal current to be expressed as an explicit analytical function of the applied terminal voltage, in contrast to the implicit-type conventional multi-exponential model. As a result this model inherently
Facta universitatis - series: Electronics and Energetics, 2014
This article presents an up-to-date review of several methods used for extraction of diode and so... more This article presents an up-to-date review of several methods used for extraction of diode and solar cell model parameters. In order to facilitate the choice of the most appropriate method for the given particular application, the methods are classified according to their lumped parameter equivalent circuit model: single-exponential, double-exponential, multiple-exponential, with and without series and parallel resistances. In general, methods based on numerical integration or optimization are recommended to reduce the possible uncertainties arising from measurement noise.
IEEE Sensors Journal
Large-area compatible, solar-blind deep-ultraviolet sensors based on active pixels are demonstrat... more Large-area compatible, solar-blind deep-ultraviolet sensors based on active pixels are demonstrated with CMOS amplifiers based on poly-Si thin-film transistors and Ga2 O3 thin-film photoresistors. The active pixel configuration sensor enables approximately 40X higher responsivity compared to a discrete sensor, and the CMOS inverter amplifier exhibits a gain of 210 V/V. The Ga2 O3-based sensors were integrated on the same substrate depositing the films using magnetron sputtering at room temperature, ensuring its compatibility with large-area applications. The responsivity of discrete Ga2 O3 sensors was evaluated at different wavelengths in the deep-ultraviolet and visible ranges, and showed a maximum responsivity of 51 A/W for a wavelength of 232 nm, with a deep-ultraviolet to visible light rejection ratio of approximately 102. The active pixel sensor was implemented as flame detector resulting in an output voltage signal of up to 2 V when the system was exposed to a flame under regular background illumination conditions.
Resumen es: Se presenta un procedimiento para convertir bidireccionalmente entre dos modelos para... more Resumen es: Se presenta un procedimiento para convertir bidireccionalmente entre dos modelos para la corriente de saturacion de transistores de pelicula delgada. Con...
The first part of this article presents the modeling of the long-channel bulk MOSFET as a particu... more The first part of this article presents the modeling of the long-channel bulk MOSFET as a particular case of the SOI MOSFET. The second part reviews compares and scrutinizes various methods to extract the threshold voltage, the effective channel and the individual values of drain and source resistances. These are important device parameters for modeling and circuit simulation.
Microelectronics Reliability, 2017
The performance of modern MOSFETs is limited by the presence of parasitic series resistances and ... more The performance of modern MOSFETs is limited by the presence of parasitic series resistances and mobility degradation. This article reviews and assesses 18 of the extraction methods currently used to determine the values of parasitic series resistances and mobility degradation from the measured drain current. The methods are separated in 3 groups: seven different methods that use the transfer characteristics of several devices having different mask channel lengths; five methods based on a single device with different drain and gate bias; six methods which account for the asymmetry between drain and source resistance.
IEEE Transactions on Electron Devices, 2015
— We propose a novel systematic procedure to individually characterize relevant physical phenomen... more — We propose a novel systematic procedure to individually characterize relevant physical phenomena that typify tunnel FETs (TFETs) in general. The procedure uses the Lambert W function to explicitly solve the subthreshold and above-threshold transfer characteristics of TFETs, as described by a recently proposed universal TFET compact model based on Kane's tunneling formulation. The resulting explicit analytic solutions may be used to numerically calculate, and thus to reveal, the terminal voltage-dependent functionalities of the device's subthreshold current swing and effective electric field. The description of the output characteristics' gate-to-source voltage dependence and saturation is also part of the procedure. The resulting functional representations of the relevant features constitute useful tools for basic device analysis and design, as well as for formulating specific mathematical descriptive models of these features. Atomistic, quantum-mechanical simulated data of an InAs homojunction TFET are used as an example to numerically and graphically illustrate the proposed characterization procedure.
This article reviews and appraises the dc lumped-parameter equivalent circuit models that have be... more This article reviews and appraises the dc lumped-parameter equivalent circuit models that have been proposed so far for representing some types of solar cells that can exhibit under certain circumstances a detrimental S-shaped concave deformation within the energy-producing fourth quadrant of their illuminated I–V characteristics. We first present a very succinct recollection of lumped-parameter equivalent circuits that are commonly used to model conventional solar cells in general. We then chronologically present and discuss lumped-parameter equivalent sub-circuits that, combined with conventional solar cell equivalent circuits, are used to specifically represent the undesired S-shaped behaviour. The mathematically descriptive equations of each complete equivalent circuit are also examined, and closed form solutions for the terminal current and voltage as explicit functions of each other are presented and discussed whenever available. While comparing the most salient features and e...
—Parasitic series resistances and mobility degradation are limiting the development of advanced M... more —Parasitic series resistances and mobility degradation are limiting the development of advanced MOSFETs. We review, scrutinize, and critically compare five parameter extraction methods that use DC data measured from a single test device. The use of a single device facilitates individual characterization and avoids the impact of device-to-device model parameter variation that affects other common methods that require using measurements from arrays of transistors with several different geometries.