The present work aims at the design of 3C-SiC Double Implanted Metal Oxide Semiconductor Field Effect Transistor (DIMOSFET) with Gaussian doping profile in drift region for high breakdown voltages. By varying the device height ‘h’, function constant m and peak concentration 𝑁0, analysis has been done for an optimum profile for high breakdown voltage. With Gaussian profile peak concentration 𝑁0 = 1016 𝑐𝑚−3 at drain end and m as 1.496 ×10−2cm, highest breakdown voltage of 6.84kV has been estimated with device height of 200μm.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Polarization insensitive switchable metamaterial absorber/reflector for X-ban...journalBEEI
A unit cell of squared shaped polarization-insensitive switchable metamaterial absorber/reflector is presented. The structure operates at 10.20 GHz under both absorber mode and reflector mode configurations. Copper wire bridging the gaps to form a circular shape structure were used as switches for operation mode selections. The structure was designed on an FR4 substrate, and the incidental wave angles were varied from 0 to 50 degrees. The structure demonstrated almost 100% absorption at resonance, 3.314 GHz percentage bandwidth at 80% as an absorber. On the other hand, as reflector, it demonstrated almost a 90% reflection and a usable bandwidth of 3.327 GHz.
Design and development of aperture coupled rectangular microstrip antenna for...eSAT Journals
Abstract This paper presents the experimental investigations carried out for obtaining wide band operation of rectangular microstrip antenna by using aperture coupled feeding technique. By incorporating U-slots with stubs on the radiating element, antenna resonates for single wideband with an impedance bandwidth of 45.61%. The antenna has two resonant peaks f1 and f2 which occurs at 12.1 GHz and 14.38 GHz with minimum return loss of −32.46 dB and −46.12 dB respectively. The lower resonant frequency f1 is closer to the fundamental resonance of the rectangular patch. The second resonant frequency f2 is due to current along the edges of U-slots and stubs of aperture coupled U-slot and stub rectangular microstrip antenna (AUSRMSA). This technique also enhances the gain to 9.96 dB which is 1.89 times more than the gain of conventional rectangular microstrip antenna (CRMA). The enhancement of impedance bandwidth and gain does not affect the nature of broadside radiation characteristics. The design concepts of antennas are presented and experimental results are discussed. Keywords: Microstrip, wide band, Aperture coupled, Slots.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Polarization insensitive switchable metamaterial absorber/reflector for X-ban...journalBEEI
A unit cell of squared shaped polarization-insensitive switchable metamaterial absorber/reflector is presented. The structure operates at 10.20 GHz under both absorber mode and reflector mode configurations. Copper wire bridging the gaps to form a circular shape structure were used as switches for operation mode selections. The structure was designed on an FR4 substrate, and the incidental wave angles were varied from 0 to 50 degrees. The structure demonstrated almost 100% absorption at resonance, 3.314 GHz percentage bandwidth at 80% as an absorber. On the other hand, as reflector, it demonstrated almost a 90% reflection and a usable bandwidth of 3.327 GHz.
Design and development of aperture coupled rectangular microstrip antenna for...eSAT Journals
Abstract This paper presents the experimental investigations carried out for obtaining wide band operation of rectangular microstrip antenna by using aperture coupled feeding technique. By incorporating U-slots with stubs on the radiating element, antenna resonates for single wideband with an impedance bandwidth of 45.61%. The antenna has two resonant peaks f1 and f2 which occurs at 12.1 GHz and 14.38 GHz with minimum return loss of −32.46 dB and −46.12 dB respectively. The lower resonant frequency f1 is closer to the fundamental resonance of the rectangular patch. The second resonant frequency f2 is due to current along the edges of U-slots and stubs of aperture coupled U-slot and stub rectangular microstrip antenna (AUSRMSA). This technique also enhances the gain to 9.96 dB which is 1.89 times more than the gain of conventional rectangular microstrip antenna (CRMA). The enhancement of impedance bandwidth and gain does not affect the nature of broadside radiation characteristics. The design concepts of antennas are presented and experimental results are discussed. Keywords: Microstrip, wide band, Aperture coupled, Slots.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An operational amplifier with recycling folded cascode topology and adaptive ...VLSICS Design
This paper presents a highly adaptive operational amplifier with high gain, high bandwidth, high speed
and low power consumption. By adopting the recycling folded cascode topology along with an adaptivebiasing
circuit, this design achieves high performance in terms of gain-bandwidth product (GBW) and slew
rate (SR). This single stage op-amp has been designed in 0.18μm technology with a power supply of 1.8V
and a 5pF load. The simulation results show that the amplifier achieved a GBW of 335.5MHz, Unity Gain
Bandwidth of 247.1MHz and a slew rate of 92.8V/μs.
Deterioration of short channel effectsijistjournal
In the proposed work, the analytical model for Surface potential and Electric field has been carried out in a
novel structure named dual halo triple material Surrounding-gate metal-oxide-semiconductor field effect
transistor (DHTMSG). The new device has been incorporated with symmetrical dual halo regions near
source and drain ends, while the gate terminal consists of three different metals with different work
functions. The results prove that the device significantly deteriorates the short channel effects which are
studied by analytical model for surface potential and electric field using parabolic approximation method.
The analytical results are endorsed by the simulation results.
Fatigue Life Assessment for Power Cables in Floating Offshore Wind TurbinesFranco Bontempi
https://www.mdpi.com/journal/energies/special_issues/Wave_Tidal_Wind_Converters
Abstract: In this paper, a procedure is proposed to determine the fatigue life of the electrical cable connected to a 5MWfloating offshore wind turbine, supported by a spar-buoy at a water depth of 320 m, by using a numerical approach that takes into account site-specific wave and wind characteristics.
The efect of the intensity and the simultaneous actions of waves and wind are investigated and the outcomes for specific cable configurations are shown. Finally, the fatigue life of the cable is
evaluated. All analyses have been carried out using the Ansys AQWA computational code, which is a commercial code for the numerical investigation of the dynamic response of floating and fixed marine structures under the combined action of wind, waves and current. Furthermore, this paper applies the FAST NREL numerical code for comparison with the ANSYS AQWA results.
Keywords: wind energy; floating offshore wind turbine; dynamic analysis; fatigue life assessment; flexible power cables.
Design of wideband Rotman lens for wireless applicationsTELKOMNIKA JOURNAL
An electrically steerable beam is an essential standard in the recent wireless application in order
to increase the gain and reduce the interference. However, high performance of amplitude besides low
phase error difficult to achieve without indicators are used to set lens parameters to desired optimum
performance design level. In this paper, the introduced microstrip lens has examined a comprehensive
explanation for parameters and indications amid a full wave structure methodology. Further, Phase and
energy coupling between excited ports and received ports besides phase error and its relation with
the lens parameters design are explained in detailed. A wideband beamforming network based on a
printed microstrip Rotman lens with a ±26o scanning angle was designed in this study. The designed lens
operates at 2.45 GHz with 592 MHz bandwidth. The lens consists of five switchable ports (input ports) with
four output ports that connected to the microstrip patch antennas. The five switchable ports were used to
realize the scanning beams angle in the azimuth plane. The proposed model is simulated by CST
Microwave Studio and fabricated on FR-4 with 1.565 mm thickness and 4.2 permittivity. A good agreement
between simulation and measurement results were achieved.
A Novel Wideband Bandpass Filter using H-shaped DGSIJECEIAES
This paper presents a novel compact wide-band bandpass filter (BPF) having good selectivity. It is designed using a dual-plane structure which consists of a parallelcoupled microstrip line on the upper surface and three H-shape defected ground structure (DGS) on the ground plane. By adding three H-shape DGS units on the ground plane, then properly adjusting their dimensions and position, the bandwidth and selectivity of the designed filter can be significantly improved. A compact prototype of wide-band microstrip bandpass filter has been designed, fabricated and measured to apply for the wireless systems. The filter shows a center frequency at 4.8 GHz, passband from 2.8 GHz to 6.8 GHz with maximum insertion loss and return loss of 0.8 dB and 40 dB, respectively. The measured results agrees well with the theoretical expectations validating the proposed design.
Optimization of Surface Impedance for Reducing Surface Waves between AntennasIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
MODELING OF BUILT-IN POTENTIAL VARIATIONS OF CYLINDRICAL SURROUNDING GATE (CS...VLSICS Design
Due to aggressive scaling of MOSFETs the parasitic fringing field plays a major role in deciding its characteristics. These fringing fields are now not negligible and should be taken into account for deriving the MOSFET models. Due to this fringing field effect there are some charges induced in the source/drain extension regions which will change the potential barrier at the source-channel from its theoretical nominal values. In this paper an attempt has been made to model variation of built-in potential variation for a cylindrical surrounding gate MOSFET. The model has been verified to be working in good agreement with the variations of gate length and channel radius.
Effect of mesh grid structure in reducing hot carrier effect of nmos device s...ijcsa
This paper presents the critical effect of mesh grid that should be considered during process and device
simulation using modern TCAD tools in order to develop and optimize their accurate electrical
characteristics. Here, the computational modelling process of developing the NMOS device structure is
performed in Athena and Atlas. The effect of Mesh grid on net doping profile, n++, and LDD sheet
resistance that could link to unwanted “Hot Carrier Effect” were investigated by varying the device grid
resolution in both directions. It is found that y-grid give more profound effect in the doping concentration,
the junction depth formation and the value of threshold voltage during simulation. Optimized mesh grid is
obtained and tested for more accurate and faster simulation. Process parameter (such as oxide thicknesses
and Sheet resistance) as well as Device Parameter (such as linear gain “beta” and SPICE level 3 mobility
roll-off parameter “ Theta”) are extracted and investigated for further different applications.
An Novel Ultra Broad-Band Exponential Taper Transmission Line 8- Port NetworkIOSRJECE
An novel Ultra Broad-Band Exponential Taper Transmission Line 8- Port Networkis analyzed. The parameters of this developed network is calculated and its frequency responses are computed. Comparison between the simulated and measured parameters are presented
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An operational amplifier with recycling folded cascode topology and adaptive ...VLSICS Design
This paper presents a highly adaptive operational amplifier with high gain, high bandwidth, high speed
and low power consumption. By adopting the recycling folded cascode topology along with an adaptivebiasing
circuit, this design achieves high performance in terms of gain-bandwidth product (GBW) and slew
rate (SR). This single stage op-amp has been designed in 0.18μm technology with a power supply of 1.8V
and a 5pF load. The simulation results show that the amplifier achieved a GBW of 335.5MHz, Unity Gain
Bandwidth of 247.1MHz and a slew rate of 92.8V/μs.
Deterioration of short channel effectsijistjournal
In the proposed work, the analytical model for Surface potential and Electric field has been carried out in a
novel structure named dual halo triple material Surrounding-gate metal-oxide-semiconductor field effect
transistor (DHTMSG). The new device has been incorporated with symmetrical dual halo regions near
source and drain ends, while the gate terminal consists of three different metals with different work
functions. The results prove that the device significantly deteriorates the short channel effects which are
studied by analytical model for surface potential and electric field using parabolic approximation method.
The analytical results are endorsed by the simulation results.
Fatigue Life Assessment for Power Cables in Floating Offshore Wind TurbinesFranco Bontempi
https://www.mdpi.com/journal/energies/special_issues/Wave_Tidal_Wind_Converters
Abstract: In this paper, a procedure is proposed to determine the fatigue life of the electrical cable connected to a 5MWfloating offshore wind turbine, supported by a spar-buoy at a water depth of 320 m, by using a numerical approach that takes into account site-specific wave and wind characteristics.
The efect of the intensity and the simultaneous actions of waves and wind are investigated and the outcomes for specific cable configurations are shown. Finally, the fatigue life of the cable is
evaluated. All analyses have been carried out using the Ansys AQWA computational code, which is a commercial code for the numerical investigation of the dynamic response of floating and fixed marine structures under the combined action of wind, waves and current. Furthermore, this paper applies the FAST NREL numerical code for comparison with the ANSYS AQWA results.
Keywords: wind energy; floating offshore wind turbine; dynamic analysis; fatigue life assessment; flexible power cables.
Design of wideband Rotman lens for wireless applicationsTELKOMNIKA JOURNAL
An electrically steerable beam is an essential standard in the recent wireless application in order
to increase the gain and reduce the interference. However, high performance of amplitude besides low
phase error difficult to achieve without indicators are used to set lens parameters to desired optimum
performance design level. In this paper, the introduced microstrip lens has examined a comprehensive
explanation for parameters and indications amid a full wave structure methodology. Further, Phase and
energy coupling between excited ports and received ports besides phase error and its relation with
the lens parameters design are explained in detailed. A wideband beamforming network based on a
printed microstrip Rotman lens with a ±26o scanning angle was designed in this study. The designed lens
operates at 2.45 GHz with 592 MHz bandwidth. The lens consists of five switchable ports (input ports) with
four output ports that connected to the microstrip patch antennas. The five switchable ports were used to
realize the scanning beams angle in the azimuth plane. The proposed model is simulated by CST
Microwave Studio and fabricated on FR-4 with 1.565 mm thickness and 4.2 permittivity. A good agreement
between simulation and measurement results were achieved.
A Novel Wideband Bandpass Filter using H-shaped DGSIJECEIAES
This paper presents a novel compact wide-band bandpass filter (BPF) having good selectivity. It is designed using a dual-plane structure which consists of a parallelcoupled microstrip line on the upper surface and three H-shape defected ground structure (DGS) on the ground plane. By adding three H-shape DGS units on the ground plane, then properly adjusting their dimensions and position, the bandwidth and selectivity of the designed filter can be significantly improved. A compact prototype of wide-band microstrip bandpass filter has been designed, fabricated and measured to apply for the wireless systems. The filter shows a center frequency at 4.8 GHz, passband from 2.8 GHz to 6.8 GHz with maximum insertion loss and return loss of 0.8 dB and 40 dB, respectively. The measured results agrees well with the theoretical expectations validating the proposed design.
Optimization of Surface Impedance for Reducing Surface Waves between AntennasIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
MODELING OF BUILT-IN POTENTIAL VARIATIONS OF CYLINDRICAL SURROUNDING GATE (CS...VLSICS Design
Due to aggressive scaling of MOSFETs the parasitic fringing field plays a major role in deciding its characteristics. These fringing fields are now not negligible and should be taken into account for deriving the MOSFET models. Due to this fringing field effect there are some charges induced in the source/drain extension regions which will change the potential barrier at the source-channel from its theoretical nominal values. In this paper an attempt has been made to model variation of built-in potential variation for a cylindrical surrounding gate MOSFET. The model has been verified to be working in good agreement with the variations of gate length and channel radius.
Effect of mesh grid structure in reducing hot carrier effect of nmos device s...ijcsa
This paper presents the critical effect of mesh grid that should be considered during process and device
simulation using modern TCAD tools in order to develop and optimize their accurate electrical
characteristics. Here, the computational modelling process of developing the NMOS device structure is
performed in Athena and Atlas. The effect of Mesh grid on net doping profile, n++, and LDD sheet
resistance that could link to unwanted “Hot Carrier Effect” were investigated by varying the device grid
resolution in both directions. It is found that y-grid give more profound effect in the doping concentration,
the junction depth formation and the value of threshold voltage during simulation. Optimized mesh grid is
obtained and tested for more accurate and faster simulation. Process parameter (such as oxide thicknesses
and Sheet resistance) as well as Device Parameter (such as linear gain “beta” and SPICE level 3 mobility
roll-off parameter “ Theta”) are extracted and investigated for further different applications.
An Novel Ultra Broad-Band Exponential Taper Transmission Line 8- Port NetworkIOSRJECE
An novel Ultra Broad-Band Exponential Taper Transmission Line 8- Port Networkis analyzed. The parameters of this developed network is calculated and its frequency responses are computed. Comparison between the simulated and measured parameters are presented
Microelectronic technology
This report briefly discusses the need for Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), their structure and principle of operation. Then it details the fabrication and characterization of the MOSFETs fabricated at the microelectronic lab at University of Malaya
shows the simulation and analysis of a MOSFET device using the MOSFet tool. Several powerful analytic features of this tool are demonstrated, including the following:
calculation of Id-Vg curves
potential contour plots along the device at equilibrium and at the final applied bias
electron density contour plots along the device at equilibrium and at the final applied bias
spatial doping profile along the device
1D spatial potential profile along the device
An Analytical Model for Fringing Capacitance in Double gate Hetero Tunnel FET...VLSICS Design
In this paper fringe capacitance of double hetero gate Tunnel FET has been studied. The physical model for fringe capacitance is derived considering source gate overlap and gate drain non overlap. Inerface trap charge and oxide charges are also introduced under positive bias stress and hot carrier stress and their effect on fringe capacitance is also studied. The fringe capacitance is significant speed limiter in Double gate technology. The model is tested by comparing with simulation results obtained from Sentauras TCAD simulations.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Design of miniaturized patch crossover based on superformula slot shapesIJECEIAES
In this paper, miniaturized microstrip crossover circuits are proposed using slots shapes obtained using the superformula. The design starts by using a conventional half-wavelength square patch crossover. For miniaturization purposes, different superformula slot shapes are introduced on the square patch. The proposed crossovers are designed to operate at 2.4 GHz using a 0.8 mm thick FR-4 substrate with a relative permittivity of 4.4. The designs are simulated using the high frequency structure simulator (HFSS). One of the miniaturized designs is fabricated and its scattering parameters are measured using a vector network analyzer. Simulated and measured results agree very well. At the design frequency, the measured input port matching is better than ˗19 dB, while 𝑆12, 𝑆13 and 𝑆14 have the values of ˗12 dB, ˗2.2 dB and ˗10 dB, respectively. Furthermore, a 71% size reduction is achieved as compared to the conventional crossover area.
DETERIORATION OF SHORT CHANNEL EFFECTS IN DUAL HALO BASED TRIPLE MATERIAL SUR...ijistjournal
In the proposed work, the analytical model for Surface potential and Electric field has been carried out in a novel structure named dual halo triple material Surrounding-gate metal-oxide-semiconductor field effect transistor (DHTMSG). The new device has been incorporated with symmetrical dual halo regions near source and drain ends, while the gate terminal consists of three different metals with different work functions. The results prove that the device significantly deteriorates the short channel effects which are studied by analytical model for surface potential and electric field using parabolic approximation method. The analytical results are endorsed by the simulation results.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Effect of Mobility on (I-V) Characteristics of Gaas MESFET Yayah Zakaria
We present in this paper an analytical model of the current–voltage (I-V) characteristics for submicron GaAs MESFET transistors. This model takes into account the analysis of the charge distribution in the active region and incorporate a field depended electron mobility, velocity saturation and charge
build-up in the channel. We propose in this frame work an algorithm of simulation based on mathematical expressions obtained previously. We propose a new mobility model describing the electric field-dependent. predictions of the simulator are compared with the experimental data [1] and
have been shown to be good.
Effect of Mobility on (I-V) Characteristics of Gaas MESFET IJECEIAES
We present in this paper an analytical model of the current–voltage (I-V) characteristics for submicron GaAs MESFET transistors. This model takes into account the analysis of the charge distribution in the active region and incorporate a field depended electron mobility, velocity saturation and charge build-up in the channel. We propose in this frame work an algorithm of simulation based on mathematical expressions obtained previously. We propose a new mobility model describing the electric field-dependent. The predictions of the simulator are compared with the experimental data [1] and have been shown to be good.
A Two-stages Microstrip Power Amplifier for WiMAX ApplicationsTELKOMNIKA JOURNAL
Amplification is one of the most basic and prevalent microwave analog circuit functions. Wherefore
power amplifiers are the most important parts of electronic circuits. This is why the designing of power
amplifiers is crucial in analog circuit designing. The intent of this work is to present an analysis and design
of a microwave broadband power amplifier by using two stages topology. A two stages power amplifier using
a distributed matching network for WiMAX applications is based on ATF-21170 (GaAs FET). The
configuration aims to achieve high power gain amplifier with low return loss over a broad bandwidth. The
proposed BPA is designed with a planar structure on an epoxy (FR4) substrate. The planar structure is also
utilized for getting the good matching condition. The advanced design system (ADS) software is used for
design, simulation, and optimization the proposed amplifier. The complete amplifier achieves an excellent
power gain; is changed between 28.5 and 20 dB with an output power of 12.45dBm at 1dB compression
point. For the input reflection coefficient (S11) is varied between -20 and -42 dB. While the output reflection
coefficient (S22) is varied between -10 dB and -49 dB over the wide frequency band of 3.2-3.8 GHz.
The differential phase shifter is an interesting four-port passive microwave network composed of two separate lines, the main line and the reference line, and providing stable phase difference between the two output signals over the specified bandwidth of interest. The most common differential phase shifter is the coupled-line Schiffman phase shifter. In this paper, a novel 90 degrees differential microstrip phase shifter configuration employing a half wavelength transmission line loaded with three open stubs is presented, the proposed design could achieve excellent performance with low phase variation over a wide bandwidth compared to the standard Schiffman phase shifter. The simulated results accomplished with the use of CST Microwave Studio and advanced design system (ADS), were found to be in good agreement and have shown that the proposed loaded-stub phase shifter achieved less than 1.1 dB insertion loss, greater than 13 dB return loss and constant 90±5 degrees phase shift over an 89 percent bandwidth.
Non-radiative wireless energy transfer with single layer dual-band printed sp...journalBEEI
Accomplishing equilibrium in terms of transfer efficiency for dual-band wireless energy transfer (WET) system remains as one of key concerns particularly in the implementation of a single transmitter device which supports simultaneous energy and data transfer functionality. Three stages of design method are discussed in addressing the aforementioned concern. A single layer dual-band printed spiral resonator for non-radiative wireless energy transfer operating at 6.78 MHz and 13.56 MHz is presented. By employing multi-coil approach, measured power transfer efficiency for a symmetrical link separated at axial distance of 30 mm are 72.34% and 74.02% at the respective frequency bands. When operating distance is varied between 30 mm to 38 mm, consistency of simulated peak transfer efficiency above 50% is achievable.
Offset effect on the S-Bend structure losses and optimization of its size for...IJECEIAES
The S-Bend structures are heavily exploited to join optical components. Reducing the power loss caused by the curve is the main objective in the design step of these components. However integrated optical circuits require S-Bend waveguide to be low loss and compact sized. In this paper, we present a contribution to link the curved structure to the straight waveguide by using the simulated bend function available in the Beam propagation tool of the Rsoft commercial software package. Simulation results confirm that this approach allows a reduction of the size of the curved structure with offset with relatively minimum of losses for photonic field.
Similar to Analysis Of 3C-Sic Double Implanted MOSFET With Gaussian Profile Doping In The Drift Region For High Breakdown Voltage (20)
Exploratory study on the use of crushed cockle shell as partial sand replacem...IJRES Journal
The increasing demand for natural river sand supply for the use in construction industry along
with the issue of environmental problem posed by the dumping of cockle shell, a by-product from cockle
business have initiated research towards producing a more environmental friendly concrete. This research
explores the potential use of cockle shell as partial sand replacement in concrete production. Cockle shell used
in this experimental work were crushed to smaller size almost similar to sand before mixed in concrete. A total
of six concrete mixtures were prepared with varying the percentages of cockle shell viz. 0%, 5%, 10%, 15%,
20% and 25%. All the specimens were subjected to continuous water curing. The compressive strength test was
conducted at 28 days in accordance to BS EN 12390. Finding shows that integration of suitable content of
crushed cockle shell of 10% as partial sand replacement able to enhance the compressive strength of concrete.
Adopting crushed cockle shell as partial sand replacement in concrete would reduce natural river sand
consumption as well as reducing the amount of cockle shell disposed as waste.
Congenital Malaria: Correlation of Umbilical Cord Plasmodium falciparum Paras...IJRES Journal
The vertical (trans-placental) transmission of the parasite Plasmodium falciparum from
pregnant mother to fetus during gestational period was investigated in a clinical research involving 43 full term
pregnant women in selected Hospitals in Jimeta Yola, Adamawa State Nigeria. During the observational study,
parasitemia was determined by light microscopic examination of umbilical and maternal peripheral blood film
for the presence of the trophozoites of Plasmodium falciparum. Correlational analysis was then carried on the
result obtained at p<0.05.><0.05) was established between maternal peripheral blood and umbilical cord
blood parasitemia with Pearson’s correlation coefficient of 0.762. Thus, in a malaria endemic area like Yola,
Adamawa State, Nigeria, with a stable transmission of parasite, there is a high probability of vertical
transmission of Plasmodium falciparum parasite from mother to fetus during gestation that can be followed by
the presentation of the symptoms of malaria by the newborn and other malaria related complications. Families
are advised to consistently sleep under appropriately treated insecticide mosquito net to avoid mosquito bite and
subsequent infestation.
Review: Nonlinear Techniques for Analysis of Heart Rate VariabilityIJRES Journal
Heart rate variability (HRV) is a measure of the balance between sympathetic mediators of heart
rate that is the effect of epinephrine and norepinephrine released from sympathetic nerve fibres acting on the
sino-atrial and atrio-ventricular nodes which increase the rate of cardiac contraction and facilitate conduction at
the atrio-ventricular node and parasympathetic mediators of heart rate that is the influence of acetylcholine
released by the parasympathetic nerve fibres acting on the sino-atrial and atrio-ventricular nodes leading to a
decrease in the heart rate and a slowing of conduction at the atrio-ventricular node. Sympathetic mediators
appear to exert their influence over longer time periods and are reflected in the low frequency power(LFP) of
the HRV spectrum (between 0.04Hz and 0.15 Hz).Vagal mediators exert their influence more quickly on the
heart and principally affect the high frequency power (HFP) of the HRV spectrum (between 0.15Hz and 0.4
Hz). Thus at any point in time the LFP:HFP ratio is a proxy for the sympatho- vagal balance. Thus HRV is a
valuable tool to investigate the sympathetic and parasympathetic function of the autonomic nervous system.
Study of HRV enhance our understanding of physiological phenomenon, the actions of medications and disease
mechanisms but large scale prospective studies are needed to determine the sensitivity, specificity and predictive
values of heart rate variability regarding death or morbidity in cardiac and non-cardiac patients. This paper
presents the linear and nonlinear to analysis the HRV.
Dynamic Modeling for Gas Phase Propylene Copolymerization in a Fluidized Bed ...IJRES Journal
A two-phase model is proposed for describing the dynamics of a fluidized bed reactor used for
polypropylene production. In the proposed model, the fluidized bed is divided into an emulsion and bubble
phase where the flow of gas is considered to be plug flow through the bubbles and perfectly mixed through the
emulsion phase. Similar previous models, consider the reaction in the emulsion phase only. In this work the
contribution of reaction in the bubble phase is considered and its effect on the overall polypropylene production
is investigated the kinetic model is combined with hydrodynamic model in order to develop a comprehensive
model for gas-phase propylene copolymerization reactor. Simulation profiles of the proposed model were
compared with those of well mixed model for the emulsion phase temperature. The simulated temperature
profile showed a lower rate of change compared to the previously reported models due to lower polymerization
rate. Model simulation showed that about 13% of the produced polymer comes from the bubble phase and this
considerable amount of polymerization in the bubbles should not be neglected in any modeling attempt.
Study and evaluation for different types of Sudanese crude oil propertiesIJRES Journal
Sudanese crude oil is regarded as one of the sweet types of crude in the world, Sulphur containing
compounds are un desirable in petroleum because they de activate the catalyst during the refining processes and
are the main source of acid rains and environmental pollution.(Mark Cullen 2001),Since it contains considerable
amount of salts and acids, it negatively impact the production facilities and transportation lines with corrosive
materials. However it suffers other problems in flow properties represented by the high viscosity and high
percentage of wax. Samples were collected after the initial and final treatment at CPF, and tested for
physical and chemical properties.wax content is in the range 23-31 weight % while asphalting content is about
0.1 weight% . Resin content is 13-7 weight % and deposits are 0.01 weight%. The carbon number distribution in
the crude is in the range 7-35 carbon atoms. The pour point vary between 39°C-42°C and the boiling point is in
the range 70 °C - 533 °C.
A Short Report on Different Wavelets and Their StructuresIJRES Journal
This article consists of basics of wavelet analysis required for understanding of and use of wavelet
theory. In this article we briefly discuss about HAAR wavelet transform their space and structures.
A Case Study on Academic Services Application Using Agile Methodology for Mob...IJRES Journal
Recently, Mobile Cloud Computing reveals many modern development areas in the Information
Technology industry. Several software engineering frameworks and methodologies have been developed to
provide solutions for deploying cloud computing resources on mobile application development. Agile
methodology is one of the most commonly used methodologies in the field. This paper presents the MCCAS a
Web and Mobile application that provide feature for the Palestinian higher education/academic institutions. An
Agile methodology was used in the development of the MCCAS but in parallel with emphasis on Cloud
computing resources deployment. Also many related issues is discussed such as how software engineering
modern methodologies (advances) influenced the development process.
Wear Analysis on Cylindrical Cam with Flexible RodIJRES Journal
Firstly, the kinetic equation of spatial cylindrical cam with flexible rod has been established. Then, an
accurate cylindrical cam mechanism model has been established based on the spatial modeling software
Solidworks. The dynamic effect of flexible rod on mechanical system was studied in detail based on the
mechanical system dynamics analytical software Adams, and Archard wear model is used to predict the wear of
the cam. We used Ansys to create finite element model of the cam link, extracted the first five order mode to
export into Adams. The simulation results show that the dynamic characteristics of spatial cylindrical cam
mechanical system with flexible rod is closed to ideal mechanism. During the cam rotate one cycle, the collision
in the linkage with a clearance occurs in some special location, others still keep a continuous contact, and the
prediction of wear loss is smaller than rigid body.
DDOS Attacks-A Stealthy Way of Implementation and DetectionIJRES Journal
Cloud Computing is a new paradigm provides various host service [paas, saas, Iaas over the internet.
According to a self-service,on-demand and pay as you use business model,the customers will obtain the cloud
resources and services.It is a virtual shared service.Cloud Computing has three basic abstraction layers System
layer(Virtual Machine abstraction of a server),Platform layer(A virtualized operating system, database and
webserver of a server and Application layer(It includes Web Applications).Denial of Service attack is an attempt
to make a machine or network resource unavailable to the intended user. In DOS a user or organization is
deprived of the services of a resource they would normally expect to have.A Successful DOS attack is a highly
noticeable event impacting the entire online user base.DOS attack is found by First Mathematical Metrical
Method (Rate Controlling,Timing Window,Worst Case and Pattern Matching)DOS attack not only affect the
Quality of the service and also affect the performance of the server. DDOS attacks are launched from Botnet-A
large Cluster of Connected device(cellphone,pc or router) infected with malware that allow remote control by an
attacker. Intruder using SIPDAS in DDOS to perform attack.SIPDAS attack strategies are detected using Heap
Space Monitoring Algorithm.
An improved fading Kalman filter in the application of BDS dynamic positioningIJRES Journal
Aiming at the poor dynamic performance and low navigation precision of traditional fading
Kalman filter in BDS dynamic positioning, an improved fading Kalman filter based on fading factor vector is
proposed. The fading factor is extended to a fading factor vector, and each element of the vector corresponds to
each state component. Based on the difference between the actual observed quantity and the predicted one, the
value of the vector is changed automatically. The memory length of different channel is changed in real time
according to the dynamic property of the corresponding state component. The actual observation data of BDS is
used to test the algorithm. The experimental results show that compared with the traditional fading Kalman filter
and the method of the third references, the positioning precision of the algorithm is improved by 46.3% and
23.6% respectively.
Positioning Error Analysis and Compensation of Differential Precision WorkbenchIJRES Journal
Positioning error is a widely problem exists in mechanism, the important factors affecting machining
precision. In order to reduce the error caused by positioning problem processing, based on the differential
workbench as the research object, using the method of theoretical analysis and experimental verification, the
analysis of positioning error mechanism and source of complete differential precision workbench error
compensation, improve the accuracy of the device, provides a method for the application of modern machine
tools. table.
Status of Heavy metal pollution in Mithi river: Then and NowIJRES Journal
The Mithi River runs through the heart of suburban Mumbai. Its path of flow has been severely
damaged due to industrialization and urbanization. The quality of water has been deteriorating ever since. The
Municipal and industrial effluents are discharged in unchecked amounts. The municipal discharge comprises
untreated domestic and sewage wastes whereas the industries are majorly discharge chemicals and other toxic
effluents which are responsible in increasing the metal load of the river. In the current study, the water is
analysed for heavy metals- Copper, Cadmium, Chromium, Lead and Nickel. It also includes a brief
understanding on the fluctuations that have occurred in the heavy metal pollution, through the compilation of
studies carried out in the area previously.
The Low-Temperature Radiant Floor Heating System Design and Experimental Stud...IJRES Journal
In order to analyze the temperature distribution of the low-temperature radiant floor heating system
that uses the condensing wall-hung boiler as the heat source, the heating system is designed according to a typical
house facing south in Shanghai. The experiments are carried out to study the effects of the supply water
temperature on the thermal comfort of the system. Eventually, the supply water temperature that makes people in
the room feel more comfortable is obtained. The result shows that in the condition of that the outside temperature
is 8~15℃ and the relative humidity is 30~70%RH, the temperature distribution in the room is from high to low
when the height is from bottom to top. The floor surface temperature is highest, but its uniformity is very poor.
When the heating system reaches the steady state, the air temperature of the room is uniform. When the supply
water temperature is 63℃ The room is relatively comfortable at the above experimental condition.
Experimental study on critical closing pressure of mudstone fractured reservoirsIJRES Journal
In the process of oil and gas exploitation of mudstone-fractured reservoir in Daqing oilfield, the
permeability of fracture is easily affected by the influence of stress change, which is shown by the sensitivity of
the permeability to the stress. With the extension of time mining in the fractured mudstone reservoir, fracture
stress sensitivity is obvious in vast decline of production and great influence on reduced yields. In order to
reasonably determine the way of developing method, working system and the exploitation rate of the reservoir,
correspondingly protecting reservoir productivity, improve ultimate recovery. On the basis of the previous
research on the stress sensitivity of fractured mudstone, this essay studied the critical closing pressure of the
simulated underground fractured mudstone under the laboratory condition.
Correlation Analysis of Tool Wear and Cutting Sound SignalIJRES Journal
With the classic signal analysis and processing method, the cutting of the audio signal in time
domain and frequency domain analysis. We reached the following conclusions: in the time domain analysis,
cutting audio signals mean and the variance associated with tool wear state change occurred did not change
significantly, and tool wear is not high degree of correlation, and the mean-square value of the audio signal
changes in the size and tool wear the state has a good relationship.
Reduce Resources for Privacy in Mobile Cloud Computing Using Blowfish and DSA...IJRES Journal
Mobile cloud computing in light of the increasing popularity among users of mobile smart
technology which is the next indispensable that enables users to take advantage of the storage cloud computing
services. However, mobile cloud computing, the migration of information on the cloud is reliable their privacy
and security issues. Moreover, mobile cloud computing has limitations in resources such as power energy,
processor, Memory and storage. In this paper, we propose a solution to the problem of privacy with saving and
reducing resources power energy, processor and Memory. This is done through data encryption in the mobile
cloud computing by symmetric algorithm and sent to the private cloud and then the data is encrypted again and
sent to the public cloud through Asymmetric algorithm. The experimental results showed after a comparison
between encryption algorithms less time and less time to decryption are as follows: Blowfish algorithm for
symmetric and the DSA algorithm for Asymmetric. The analysis results showed a significant improvement in
reducing the resources in the period of time and power energy consumption and processor.
Resistance of Dryland Rice to Stem Borer (Scirpophaga incertulas Wlk.) Using ...IJRES Journal
Rice stem borer is one of the important pests that attack plants so as to reduce production. One way
to control pests is to use organic fertilizers that make the plant stronger and healthier. This study was conducted
to determine the effects of organic fertilizers with various doses without the use of pesticides in controlling stem
borer, Scirpophaga incertulas. Methods using split-split plot design which consists of two levels of the whole
plot factor (solid and liquid organic fertilizers), two levels of the subplot factor (conventional and industry,
Tiens and Mitraflora), and four levels of the sub-subplot factor of conventional and industry (5, 10, 15, 20
tonnes/ha), and one level of the sub-subplot factor of Tiens and Mitraflora (each 2 ml/l). Based on the results
Statistical analysis there were no significant differences among treatments and this shows that the use of organic
fertilizers that only a dose of 5 tonnes/ha is sufficient available nutrients that make plants more robust and
resistant to control stem borer, besides that can reduce production costs and friendly to the environment when
compared with using inorganic fertilizers.
A novel high-precision curvature-compensated CMOS bandgap reference without u...IJRES Journal
A novel high-precision curvature-compensated bandgap reference (BGR) without using op-amp
is presented in this paper. It is based on second-order curvature correction principle, which is a weighted sum of
two voltage curves which have opposite curvature characteristic. One voltage curve is achieved by first-order
curvature-compensated bandgap reference (FCBGR) without using op-amp and the other found by using W
function is achieved by utilizing a positive temperature coefficient (TC) exponential current and a linear
negative TC current to flow a linear resistor. The exponential current is gained by using anegative TC voltage to
control a MOSFET in sub-threshold region. In the temperature ranging from -40℃ to 125℃, experimental
results implemented with SMIC 0.18μm CMOS process demonstrate that the presented BGR can achieve a TC
as low as 2.2 ppm/℃ and power-supply rejection ratio(PSRR)is -69 dB without any filtering capacitor at 2.0 V.
While the range of the supply voltage is from 1.7 to 3.0 V, the output voltage line regulation is about1 mV/ V
and the maximum TC is 3.4 ppm/℃.
Structural aspect on carbon dioxide capture in nanotubesIJRES Journal
In this work we reported the carbon dioxide adsorption (CO2) in six different nanostructures in order
to investigate the capturing capacity of the materials at nanoscale. Here we have considered the three different
nanotubes including zinc oxide nanotube (ZnONT), silicon carbide nanotube (SiCNT) and single walled carbon
nanotube (SWCNT). Three different chiralities such as zigzag (9,0), armchair (5,5) and chiral (6,4) having
approximately same diameter are analyzed. The adsorption binding energy values under various cases are
estimated with density functional theory (DFT). We observed CO2 molecule chemisorbed on ZnONT and
SiCNT’s whereas the physisorption is predominant in CNT. To investigate the structural aspect, the tubes with
defects are studied and compared with defect free tubes. We have also analyzed the electrical properties of tubes
from HOMO, LUMO energies. Our results reveal the defected structure enhance the CO2 capture and is
predicted to be a potential candidate for environmental applications.
Thesummaryabout fuzzy control parameters selected based on brake driver inten...IJRES Journal
In this paper, the brake driving intention identification parameters based on the fuzzy control are
summarized and analyzed, the necessary parameters based on the fuzzy control of the brake driving intention
recognition are found out, and I pointed out the commonly corrupt parameters, and through the relevant
parameters , I establish the corresponding driving intention model.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
block diagram and signal flow graph representation
Analysis Of 3C-Sic Double Implanted MOSFET With Gaussian Profile Doping In The Drift Region For High Breakdown Voltage
1. International Journal of Research in Engineering and Science (IJRES)
ISSN (Online): 2320-9364, ISSN (Print): 2320-9356
www.ijres.org Volume 2 Issue 1 ǁ Jan 2014 ǁ PP.36-39
www.ijres.org 36 | Page
Analysis Of 3C-Sic Double Implanted MOSFET With Gaussian
Profile Doping In The Drift Region For High Breakdown Voltage
Parag Parashar1
, Ashoke Kumar Chatterjee2
1
(Department of Electronics and Communication, Amity University, Gurgaon-122413, India)
2
(Department of Electronics and Communication, Thapar University, Patiala - 147004, India)
ABSTRACT: The present work aims at the design of 3C-SiC Double Implanted Metal Oxide Semiconductor
Field Effect Transistor (DIMOSFET) with Gaussian doping profile in drift region for high breakdown voltages.
By varying the device height ‘h’, function constant m and peak concentration 𝑁0, analysis has been done for an
optimum profile for high breakdown voltage. With Gaussian profile peak concentration 𝑁0 = 1016
𝑐𝑚−3
at
drain end and m as 1.496 × 10−2
cm, highest breakdown voltage of 6.84kV has been estimated with device height
of 200µm.
Keywords - Avalanche breakdown voltage, DIMOSFET, Punch through breakdown voltage, Silicon carbide
(SiC).
I. Introduction
Silicon carbide (SiC) is a potential compound semiconductor for high temperature, high frequency and
high power electronic applications due of its wide band gap, high value of saturated drift velocity, high
breakdown electric field and high thermal conductivity. SiC exists in different polytypes where difference
between these lies in the stacking order between the double layers of carbon and silicon atoms. Among other
polytypes, the most important are cubic (3C) and hexagonal (4H and 6H) forms. The distinct polytypes differ in
both band gap energies and electronic properties. Thus band gap varies with the polytype from 2.2eV for 3C-
SiC over 3.0eV for 6H-SiC to 3.2eV for 4H-SiC. 3C- SiC polytype has many advantages compared to other
polytypes such as isotropic electron Hall mobility [1] (due to low density of interface states), smaller band gap
that permits “inversion” at lower electric field strengths. Also the interface states observed in 6H-SiC and 4H-
SiC are located in the band gap close to conduction band edge, limiting the transport of electrons in the channel
[2]. Due to the smaller band gap of 3C-SiC, observed interface states are located in conduction band and thus
have no effect on the transport properties of the channel .The 3C-SiC polytype has lower critical electric field
value due to smaller band gap. Thus for a given blocking voltage, specific junction capacitance will be lower in
the 3C-SiC devices as compared to the 4H-SiC and 6H-SiC due of lower drift region doping[2]. This is an
advantage for the high speed MOSFETs.
However research pertaining to SiC power devices and their practical application has been held back by lack
of reproducible techniques to grow semiconductor quality single crystals and epilayers. Over the last few years
considerable progress has been made mainly in the development of 4H and 6H - SiC wafers and the related
devices. However, there is a deviation of the SiC device parameters from theoretical expectations and cost of
these wafers also remains high. So there is a significant interest in low cost, large size 3C-SiC wafers for various
microelectronic applications. A lot of work is being done in the area of structural characterization and crystal
growth in order to get defect free 3C-SiC wafers [3-8]. Till now, large mono-crystal 3C-SiC substrates (at least
200 µm thick, six inch in diameter, after removing the Si base layer), can be manufactured with the help of a
new process originated by HOYA Corporation, Japan [9]. Thus, in this paper height of device does not exceed
beyond 200 µm. HOYA's 3C-SiC substrate has the same geometry as typical Silicon wafers and can be used in
conventional Silicon semiconductor device production lines without hardware modifications.
II. Analysis of DIMOSFET for high breakdown voltage
The fabrication of DIMOSFET structure is normally done by using planar diffusion technology with a
gate such as poly silicon. In these devices, the edge of the poly silicon gate serves as a common window for the
diffusion of p-base and n+ - source regions. Fig.1 shows a cross section of a power DIMOSFET structure.
Difference in the lateral diffusion between the p-base and n+ source region defines the surface channel region
[10]. The forward blocking capability is achieved by the p-n junction between the p-base region and the n-drift
region. During the device operation, a fixed potential to the p-base region is provided by the connection of base
to the source metal through a break in the n+ source region. By applying a positive bias to the drain and short-
circuiting the gate to the source, the p-base and n-drift region junction becomes reverse-biased thus supporting
the drain voltage by the extension of a depletion layer on both sides of the junction [10]. However, the depletion
layer extends primarily into the n-drift region due to its lower doping level as compared to p-base region. A
2. Analysis of 3C-SiC double implanted MOSFET with Gaussian profile doping in the drift region for
www.ijres.org 37 | Page
conductive path extending between the n+ - source region and the n-drift region is formed by applying positive
bias to the gate electrode. The application of a positive drain voltage results in a current flow between drain and
source through the n-drift region and conductive channel.
Fig.1. Structure of basic DIMOSFET [10]
Doping profiles used in semiconductor industry commercially normally employ non-linearly graded
profiles inside semiconductor layers. Gaussian or Complementary Error Function distribution is the most
preferred profiles for improved results [11]. This work analyses the device structure of vertical DIMOSFET
with Gaussian Profile doping in the drift region as shown in Fig.2. The Gaussian profile has been adopted with
the peak lying at the drain end of the device and the doping concentration falls to small values near the n-drift
region and p-base junction. This procedure provides a low parasitic series resistance near the drain and a large
depletion region in the drift region near the junction.
The equation for Gaussian profile is written as [11]:
G(x) =𝑁0 𝑒𝑥𝑝−
ℎ−𝑥
𝑚
2
(1)
𝑁0 is the maximum concentration at the drain end, „h‟ is device height, m is a function constant. The depletion
region width at any given reverse voltage VR can be obtained by solving the Poisson‟s equation for the system
For the Gaussian function G(x), the Poisson‟s equation becomes [11]:
- 𝜕2
𝑉/𝜕2
𝑥 = (e/ɛ 𝑠) G(x) = (e𝑁0/ɛ 𝑠) 𝑒𝑥𝑝−
ℎ−𝑥
𝑚
2
(2)
Fig. 2. Cross-sectional structure of DIMOSFET showing Gaussian profile in the drift region [11]
ɛ 𝑠 is relative permittivity of medium and e is the charge of an electron.
Solving the above equation for voltage V with proper initial conditions and first order error function
approximation [11] :
-V(x) = (𝑒𝑁0/ ɛ 𝑠) [(𝑥4
12𝑚2
) - (ℎ 𝑥3
3 𝑚2
) - (𝑥2
2) (1 − ℎ2
𝑚2
)] (3)
At x=W, the depletion region width under a reverse bias VR is given as:
V (W) = Vbi + VR
where Vbi is the built-in potential.
Substituting x=W and V (W) = -VR (as VR >>Vbi ) in eq. (3), gives [11]:
[(𝑊4
12𝑚2
) - (ℎ 𝑊3
3 𝑚2
) - (𝑊2
2)(1 − ℎ2
𝑚2
)] - (ɛ 𝑠 VR 𝑒𝑁0) = 0 (4)
3. Analysis of 3C-SiC double implanted MOSFET with Gaussian profile doping in the drift region for
www.ijres.org 38 | Page
Above equation has been used to calculate the depletion region width W at a given reverse bias voltage VR
between the p-body and n-drift region of DIMOSFET.
III. Punch through breakdown voltage 𝐕 𝐁𝐏𝐓 and Avalanche breakdown voltage 𝐕 𝐁𝐀𝐕
The device height has been set at 200µm and 150µm for various values of m and doping level in the
drift region. Analysis of equation (4) has been done in order to increase the reverse voltage VR to a value for
which maximum depletion width does not go beyond the device height. That maximum value of reverse voltage
is taken as Punch through breakdown voltageVBPT .
Avalanche breakdown voltage VBAV has been calculated by approximating Gaussian profile as linearly
graded profile in the drift region. This approximation is valid for large device heights as considered here. For
linearly graded profile avalanche breakdown voltage is given by [12]:
VBAV = (2/3) Ec W′
(5)
where Ec is the critical field which is given by [12]:
Ec = (e α W′2
/8ɛs) (6)
where α is concentration gradient, W′
is depletion region width at breakdown.
Concentration gradient α was obtained by taking the difference of carrier concentrations at the source and
drain end and dividing it by the device height „h‟. Calculations of two breakdown voltages (punch through and
avalanche) are done by using same depletion region width.
IV. Results and Calculations
Calculations of punch through breakdown voltages (VBPT ) and avalanche breakdown voltages (VBAV )
were made for three Gaussian profiles. Table1 shows three results with critical field 𝐸𝑐 and concentration
gradient α.
Table 1. Results of breakdown voltages (VBPT and VBAV ) for various profiles
Profiles Device
Height
(µm)
m
( µm)
N0
( cm−3
)
α
( cm−4
)
EC
(V/cm)
VBPT
(kV)
VBAV
(kV)
1. 200 100 0.67× 1015
3.29× 1016
3.08× 105 25 4.106
2. 150 78 1.1× 1015
7.16× 1016
3.767× 105 19.6 3.767
3. 200 149.6 1016
4.17× 1017
10.09× 105 25 6.84
The Gaussian profiles that are given above are shown in Fig. 3 with peak concentration of N0 . Doping
level is minimum near the source end and maximum at the drain end.
Fig.3. Variation of G(x) vs. x for various profiles in semi-log scale
For the first and third profile, the drain to source distance or device height „h‟ has been set as 200µm.
The second profile utilizes a device height of 150µm, as increasing the device height beyond this thickness leads
to a decline in the avalanche breakdown voltage. The analysis of depletion region width and reverse voltage for
all three profiles is shown in Fig. 4. To a first approximation the relationship between the two can be considered
as almost linear over the range of 0 to 25 kV for a device height of 150 to 200µm. A slight amount of non
linearity seems to exist in three profiles for reverse voltages lying between 0 to 5 kV and 20 to 25 kV.
4. Analysis of 3C-SiC double implanted MOSFET with Gaussian profile doping in the drift region for
www.ijres.org 39 | Page
Fig.4. Variation of Depletion region width vs. Reverse voltage for the three profiles
Hence it is clear that profile 3 with a device height of 200 µm, m = 1.496× 10−2
cm, N0 = 1016
/cc, α =
4.17× 1017
cm−4
is expected to provide the highest avalanche breakdown voltage of 6.84 kV corresponding to
a punch through voltage of 25 kV. Analysis quoted above gives the breakdown voltage of 6.84 kV for Gaussian
profile in profile 3 but the design procedure does point to one disadvantage that there is significant difference in
the values of punch through breakdown voltage VBPT and avalanche breakdown voltage VBAV in all the profiles
that have been studied.
V. Conclusion
Analysis of different profiles have been done to calculate maximum breakdown voltage for the device
as shown in Table 1.For the drift region height h=200µm, N0 = 1016
/cm3
and m = 1.496× 10−2
cm, the punch
through breakdown voltage was found to be 25kV and corresponding avalanche breakdown voltage was
calculated as 6.84kV when Gaussian profile was approximated as linearly graded profile in drift region. So,
under the constraints of device height, peak concentration and function constant, the maximum breakdown
voltage for the device is estimated as 6.84 kV. It could be seen that avalanche breakdown will occur much
before than punch through breakdown. More detailed analysis is required in the use of Gaussian profile in drift
region that can yield almost equal values for punch through and avalanche breakdown voltages for 3C-SiC
DIMOSFET. Having attained this, it would be advisable to analyze the theory for attaining breakdown voltages
far in excess of the avalanche breakdown voltage of 6.84 kV obtained here.
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