The document discusses electrical measurements for semiconducting devices. It describes current-voltage (I-V) characteristics and capacitance-voltage (C-V) characteristics, which are important for understanding the performance of solar cells and other semiconductor applications. The I-V characteristics provide information about the ideality factor and barrier potential of devices like diodes and solar cells. C-V measurements allow determining parameters like doping concentration and flat band potential. Understanding these electrical measurements is key to improving the efficiency of devices using heterojunctions of wide bandgap semiconductors.
Capacitance-voltage Profiling Techniques for Characterization of Semiconduct...eeiej_journal
A new capacitance-voltage profiling technique of semiconductor junctions is proposed for characterisation of semiconductor materials and devices. The measurement technique is simple, non-destructive and it has a greater accuracy compared with the classical C-V method of J. Hilibrand and R. D. Gold, developed in 1960.
The document discusses the electro-optical properties of semiconductors under an applied electric field. It describes the Franz-Keldysh effect where an electric field causes a red shift and broadening of the band edge absorption in bulk semiconductors. It also discusses the Stark effect which modifies the excitonic absorption due to changes in the electron-hole interaction. When applied to quantum wells, the electric field can cause a quantum-confined Stark effect or quantum-confined Franz-Keldysh effect, broadening excitonic resonances and allowing forbidden transitions.
This document presents the results of a simulation study on nano metal-semiconductor contacts. It includes theoretical background on conventional and nano-scale Schottky diodes. Finite element simulations using COMSOL were conducted to analyze the electric potential, field, and depletion width for different metal particle radii and doping concentrations. The simulations demonstrated enhanced built-in potential and electric field at the interface for smaller radii. Comparisons between theoretical predictions and simulation results showed good agreement. Overall, the study revealed improved characteristics for nano-scale contacts compared to conventional planar contacts.
This document provides an overview of circuit theory concepts including:
- Electric circuits are interconnections of electrical elements.
- Charge is the most basic quantity and is measured in coulombs. Current is the rate of charge flow measured in amperes.
- Voltage is the energy required to move a unit charge through a circuit element and is measured in volts.
- Power is the rate of energy use/production and is measured in watts.
- Circuit elements include passive (resistors, capacitors, inductors) and active (sources) components. Kirchhoff's laws and Ohm's law govern circuit analysis.
- Nodal and mesh analysis provide systematic techniques for analyzing circuits by
NanoScale TiO2 based Memory Storage Circuit Element:- MemristorAM Publications
This document discusses the memristor, a fourth fundamental circuit element predicted by Leon Chua in 1971. In 2008, HP Laboratories created the first physical model of a memristor using a thin film of titanium dioxide sandwiched between platinum electrodes. This memristor exhibits variable resistance depending on the charge that has passed through it, fulfilling Chua's prediction. While this initial design had limitations like low speed and heat dissipation, memristors show potential for applications like non-volatile memory, neuromorphic computing, and new circuit designs. Further research is still needed to improve memristor models and address challenges for practical applications.
B.tech sem i engineering physics u i chapter 2-dielectricsRai University
Dielectrics are materials that can be polarized by an applied electric field. There are several types of polarization that can occur in dielectric materials including electronic, ionic, orientation and space charge polarization. The relative permittivity or dielectric constant of a material indicates how much it increases the capacitance of a capacitor placed in the material. Polarization occurs when the electric field causes a separation of electric charges in the material, creating electric dipoles. The electric displacement vector D accounts for the effect of polarization on the electric field strength inside the material.
This document contains physics examination papers from 2008-2012 administered by the Central Board of Secondary Education (CBSE) in Delhi, India. It lists the contents which include CBSE examination papers from Delhi and All India in those years, as well as foreign papers. A sample paper from the 2008 Delhi exam is then provided, consisting of 30 multiple choice questions testing concepts in physics.
Capacitance-voltage Profiling Techniques for Characterization of Semiconduct...eeiej_journal
A new capacitance-voltage profiling technique of semiconductor junctions is proposed for characterisation of semiconductor materials and devices. The measurement technique is simple, non-destructive and it has a greater accuracy compared with the classical C-V method of J. Hilibrand and R. D. Gold, developed in 1960.
The document discusses the electro-optical properties of semiconductors under an applied electric field. It describes the Franz-Keldysh effect where an electric field causes a red shift and broadening of the band edge absorption in bulk semiconductors. It also discusses the Stark effect which modifies the excitonic absorption due to changes in the electron-hole interaction. When applied to quantum wells, the electric field can cause a quantum-confined Stark effect or quantum-confined Franz-Keldysh effect, broadening excitonic resonances and allowing forbidden transitions.
This document presents the results of a simulation study on nano metal-semiconductor contacts. It includes theoretical background on conventional and nano-scale Schottky diodes. Finite element simulations using COMSOL were conducted to analyze the electric potential, field, and depletion width for different metal particle radii and doping concentrations. The simulations demonstrated enhanced built-in potential and electric field at the interface for smaller radii. Comparisons between theoretical predictions and simulation results showed good agreement. Overall, the study revealed improved characteristics for nano-scale contacts compared to conventional planar contacts.
This document provides an overview of circuit theory concepts including:
- Electric circuits are interconnections of electrical elements.
- Charge is the most basic quantity and is measured in coulombs. Current is the rate of charge flow measured in amperes.
- Voltage is the energy required to move a unit charge through a circuit element and is measured in volts.
- Power is the rate of energy use/production and is measured in watts.
- Circuit elements include passive (resistors, capacitors, inductors) and active (sources) components. Kirchhoff's laws and Ohm's law govern circuit analysis.
- Nodal and mesh analysis provide systematic techniques for analyzing circuits by
NanoScale TiO2 based Memory Storage Circuit Element:- MemristorAM Publications
This document discusses the memristor, a fourth fundamental circuit element predicted by Leon Chua in 1971. In 2008, HP Laboratories created the first physical model of a memristor using a thin film of titanium dioxide sandwiched between platinum electrodes. This memristor exhibits variable resistance depending on the charge that has passed through it, fulfilling Chua's prediction. While this initial design had limitations like low speed and heat dissipation, memristors show potential for applications like non-volatile memory, neuromorphic computing, and new circuit designs. Further research is still needed to improve memristor models and address challenges for practical applications.
B.tech sem i engineering physics u i chapter 2-dielectricsRai University
Dielectrics are materials that can be polarized by an applied electric field. There are several types of polarization that can occur in dielectric materials including electronic, ionic, orientation and space charge polarization. The relative permittivity or dielectric constant of a material indicates how much it increases the capacitance of a capacitor placed in the material. Polarization occurs when the electric field causes a separation of electric charges in the material, creating electric dipoles. The electric displacement vector D accounts for the effect of polarization on the electric field strength inside the material.
This document contains physics examination papers from 2008-2012 administered by the Central Board of Secondary Education (CBSE) in Delhi, India. It lists the contents which include CBSE examination papers from Delhi and All India in those years, as well as foreign papers. A sample paper from the 2008 Delhi exam is then provided, consisting of 30 multiple choice questions testing concepts in physics.
The document is the question paper for a CBSE Board Examination for Physics (Theory).
[1] It contains 30 questions ranging from very short answer to long answer questions. [2] The questions cover various topics in Physics including electromagnetism, optics, semiconductor properties, and magnetic materials. [3] Instructions are provided on how to attempt the paper and the marking scheme for different types of questions.
Numerical computation of eigenenergy and transmission coefficient of symmetri...IAEME Publication
This document summarizes a study on numerically computing the eigenenergy and transmission coefficient of a symmetric quantum double barrier structure with variable effective mass under an applied electric field. The study uses the transfer matrix method to solve Schrodinger's equation for a GaAs/AlxGa1-xAs material system. It finds that eigenenergy decreases nonlinearly with increasing electric field. Transmission coefficient decreases with increasing barrier thickness or height but can occur at lower energies with increasing well thickness. The existence of higher quasi-bound states is also observed.
Dielectrics are materials that contain permanently aligned electric dipoles. When an electric field is applied, the dipoles in dielectric materials can undergo several types of polarization, including electronic, ionic, orientational, and space charge polarization. This polarization leads to an increase in the electric flux density and dielectric constant within the material. The dielectric constant is the ratio of the material's permeability to the permeability of free space and determines the material's behavior in electric fields.
The document describes an experiment to observe quantized conductance in gold wire nanocontacts. A circuit is constructed using batteries, resistors, and an operational amplifier to apply a voltage between two gold wires and measure the current as the wires are slowly separated. Quantized steps in the conductance are expected as the contact width decreases to the nanoscale due to the quantum confinement of electron transport. Students will perform the experiment, record oscilloscope measurements of the conductance steps for both gold and solder wires, and analyze the results to determine if they match theoretical predictions.
Electrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materials
TIME-VARYING FIELDS AND MAXWELL's EQUATIONS -Unit 4 - two marksDr.SHANTHI K.G
1. The document contains 28 questions and answers related to time varying fields and Maxwell's equations. It covers topics like Faraday's law, Lenz's law, motional emf, transformer emf, Maxwell's equations in differential and integral form, constitutive relations, boundary conditions, and vector wave equations.
2. Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents. The document provides the equations of Maxwell's equations in various forms for different materials and conditions like free space, good conductors, and harmonically varying fields.
3. Key concepts covered include displacement current, retarded potentials, phasors, and the wave nature of electromagnetic fields. Maxwell
Hamiltonian Approach for Electromagnetic Field in One-dimensional Photonic Cr...IRJET Journal
1) The document presents a novel Hamiltonian approach for determining the classical electromagnetic field distribution in one-dimensional photonic crystals.
2) The approach starts from a microscopic Hamiltonian describing the interaction between quantized electromagnetic fields and medium oscillators. Approximations are made to derive a macroscopic Hamiltonian in terms of averaged field operators and material susceptibilities.
3) Using the macroscopic Hamiltonian and coherent states of the electromagnetic field, the electric field operator for the photonic crystal is obtained. The expectation value of this operator gives the classical electric field distribution inside the photonic crystal.
4) As an example, the electric field distribution in a one-dimensional photonic crystal of alternating dielectric layers is determined and a phot
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.
The document discusses a workshop organized by KV Andrews Ganj to prepare sample higher-order thinking (HOT) questions for Class XII Physics. [1] A two-day workshop was held in July 2008 with 10 Physics teachers from various KVs participating. [2] The teachers worked to computerize chapter-wise sample HOT questions for CBSE Class XII Physics. [3] The principal expresses that this material will help students and teachers perform better in board exams, while noting that teachers can prepare additional questions to improve student competency.
The document summarizes research on understanding charge transport in low dimensional semiconductor nanostructures embedded in an insulating matrix. Specifically, it examines current-voltage characteristics of germanium nanowire arrays in an alumina matrix as a function of temperature. Key findings include:
1) At room temperature, conduction follows Ohm's law at low voltages and Mott-Gurney's space charge limited current law at higher voltages.
2) With decreasing temperature, conduction transitions from a trap-free regime to an exponentially distributed trap regime.
3) Mobility decreases with decreasing temperature, and activation energy is extracted from an Arrhenius plot, found to be 85 meV at low temperatures and 301 meV
This document presents a novel stochastic approach for assessing the lightning performance of overhead transmission lines (OHLs). It combines systematic simulations using an accurate EMTP model of a 110 kV OHL with probability distribution functions obtained statistically. The probabilities of different outcomes, like the number of insulator string flashovers from a direct lightning strike, are calculated. These "stochastic lightning performance characteristics" provide a meaningful way to compare the lightning performance of different OHL configurations. The approach is demonstrated through simulations of a 110 kV line in Ireland that had experienced lightning issues.
Physics Sample Paper with General Instruction for Class - 12Learning Three Sixty
Learning 360 brings “Physics sample paper” for CLASS – 12. This document also carries 31 questions with solution of each given question for better understanding of the students. Download for free now; http://www.learning360.net/study_hub/1090-2/
Some Aspects of Stress Distribution and Effect of Voids Having Different Gase...IOSR Journals
1) The document analyzes the stress distribution and effect of voids with different gases in MV power cables through finite element modeling. It studies the electric field and temperature distribution within cable insulation containing voids.
2) Cylindrical voids are found to have higher electric stress than spherical or elliptical voids. Among gases, oxygen consumption during partial discharge causes greater temperature rise and faster breakdown than nitrogen.
3) The analysis examines factors like void shape, position, and size that influence stress distribution and partial discharge inception voltage. Nearer and larger voids have lower inception voltages. Oxygen consumption leads to uniform erosion and higher temperatures, making its effect greater than other gases.
This document discusses plane wave reflection from a media interface. It begins by introducing the concepts of reflection and transmission coefficients which describe how much of an incident wave is reflected or transmitted at a boundary. It then examines plane wave reflection at normal incidence, deriving expressions for the reflected and transmitted electric and magnetic fields in two lossy media. Boundary conditions requiring the tangential field components to be continuous are applied to obtain equations relating the reflection and transmission coefficients to the material properties on either side of the interface.
Semiconductors have electrical properties between conductors and insulators. They behave as insulators at low temperatures but conduct electricity at room temperature due to their small band gap. Doping semiconductors with impurities creates an excess of electrons or holes, making them n-type or p-type. A p-n junction is formed at the boundary between p-type and n-type semiconductors and allows current to flow in only one direction, making it useful for diodes. Diodes are used to convert alternating current to direct current and have many applications in electronics.
This document provides an introduction to basic electrical concepts including charge, current, voltage, power, energy, and circuit elements. It defines the international system of units used in electrical engineering. Key concepts covered include defining the ampere as the unit of current representing the flow of electric charge, defining voltage as the work required to move a unit of charge from one point to another, and defining power as the rate at which energy is transferred. Circuit analysis techniques are introduced for studying the behavior of electric circuits.
This document discusses electromagnetic field theory and computational electromagnetics. It introduces electromagnetic theory, which is divided into electrostatics, magnetostatics, and time-varying fields. Computational electromagnetics is presented as a way to numerically solve electromagnetic problems using computers. Different types of equation solvers are described, including integral equation solvers and differential equation solvers. General coordinate systems and transformations between coordinate systems are also covered.
The document discusses the theory of solids, specifically semiconductors, conductors, and insulators. It describes the energy band structure and forbidden energy gaps that determine whether a material is a semiconductor, conductor, or insulator. It also discusses PN junction diodes, their I-V characteristics, and applications in rectifiers. Transistors are also briefly introduced.
This document summarizes the key electrical properties of metals and semiconductors. It discusses Ohm's law and how electrical conductivity in metals is influenced by drift velocity and current density. It also explains how resistivity is related to temperature in metals. For semiconductors, it describes the band structure of insulators, metals and semiconductors and how conductivity varies with intrinsic carrier concentration and temperature in intrinsic semiconductors. It then discusses the effects of doping on carrier concentrations and conductivity in n-type and p-type extrinsic semiconductors. Finally, it provides an overview of compound semiconductors made of two or three elements.
This document provides a brief introduction to bioimpedance, which refers to the electrical properties of biological tissue measured when current flows through it. It discusses how resistance and capacitance are the two basic properties affecting bioimpedance. Resistance opposes the flow of current, while capacitance allows alternating but not direct current to pass through. When current passes through tissue, it encounters resistance in the extracellular space at low frequencies but both resistance and capacitance at higher frequencies as it can then enter cells. Cole-Cole plots are used to display how impedance changes with frequency based on the resistance and capacitance properties of tissue.
This chapter discusses electrical conduction processes in materials and semiconductor devices. It begins by describing conduction in metals, semiconductors, and doped semiconductors. Next, it covers the p-n junction, including the formation of a space-charge layer and drift and diffusion currents. The characteristics of the p-n junction and diode are then explained. The chapter concludes by discussing maximum power dissipation and voltage limitations in diodes due to avalanche and Zener breakdown.
This document discusses semiconductor materials and their properties. It explains that semiconductors have a conductivity between insulators and metals due to their band gap. The size of the band gap determines whether a material is a semiconductor or insulator. Doping semiconductors by adding impurities can increase or decrease the number of charge carriers, tuning the material's electronic properties. Metal contacts to semiconductors can form rectifying Schottky barriers or ohmic contacts depending on the barrier height and width. Schottky diodes use a Schottky barrier for rectification while ohmic contacts are used for signals in semiconductor devices.
The document is the question paper for a CBSE Board Examination for Physics (Theory).
[1] It contains 30 questions ranging from very short answer to long answer questions. [2] The questions cover various topics in Physics including electromagnetism, optics, semiconductor properties, and magnetic materials. [3] Instructions are provided on how to attempt the paper and the marking scheme for different types of questions.
Numerical computation of eigenenergy and transmission coefficient of symmetri...IAEME Publication
This document summarizes a study on numerically computing the eigenenergy and transmission coefficient of a symmetric quantum double barrier structure with variable effective mass under an applied electric field. The study uses the transfer matrix method to solve Schrodinger's equation for a GaAs/AlxGa1-xAs material system. It finds that eigenenergy decreases nonlinearly with increasing electric field. Transmission coefficient decreases with increasing barrier thickness or height but can occur at lower energies with increasing well thickness. The existence of higher quasi-bound states is also observed.
Dielectrics are materials that contain permanently aligned electric dipoles. When an electric field is applied, the dipoles in dielectric materials can undergo several types of polarization, including electronic, ionic, orientational, and space charge polarization. This polarization leads to an increase in the electric flux density and dielectric constant within the material. The dielectric constant is the ratio of the material's permeability to the permeability of free space and determines the material's behavior in electric fields.
The document describes an experiment to observe quantized conductance in gold wire nanocontacts. A circuit is constructed using batteries, resistors, and an operational amplifier to apply a voltage between two gold wires and measure the current as the wires are slowly separated. Quantized steps in the conductance are expected as the contact width decreases to the nanoscale due to the quantum confinement of electron transport. Students will perform the experiment, record oscilloscope measurements of the conductance steps for both gold and solder wires, and analyze the results to determine if they match theoretical predictions.
Electrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materials
TIME-VARYING FIELDS AND MAXWELL's EQUATIONS -Unit 4 - two marksDr.SHANTHI K.G
1. The document contains 28 questions and answers related to time varying fields and Maxwell's equations. It covers topics like Faraday's law, Lenz's law, motional emf, transformer emf, Maxwell's equations in differential and integral form, constitutive relations, boundary conditions, and vector wave equations.
2. Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents. The document provides the equations of Maxwell's equations in various forms for different materials and conditions like free space, good conductors, and harmonically varying fields.
3. Key concepts covered include displacement current, retarded potentials, phasors, and the wave nature of electromagnetic fields. Maxwell
Hamiltonian Approach for Electromagnetic Field in One-dimensional Photonic Cr...IRJET Journal
1) The document presents a novel Hamiltonian approach for determining the classical electromagnetic field distribution in one-dimensional photonic crystals.
2) The approach starts from a microscopic Hamiltonian describing the interaction between quantized electromagnetic fields and medium oscillators. Approximations are made to derive a macroscopic Hamiltonian in terms of averaged field operators and material susceptibilities.
3) Using the macroscopic Hamiltonian and coherent states of the electromagnetic field, the electric field operator for the photonic crystal is obtained. The expectation value of this operator gives the classical electric field distribution inside the photonic crystal.
4) As an example, the electric field distribution in a one-dimensional photonic crystal of alternating dielectric layers is determined and a phot
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.
The document discusses a workshop organized by KV Andrews Ganj to prepare sample higher-order thinking (HOT) questions for Class XII Physics. [1] A two-day workshop was held in July 2008 with 10 Physics teachers from various KVs participating. [2] The teachers worked to computerize chapter-wise sample HOT questions for CBSE Class XII Physics. [3] The principal expresses that this material will help students and teachers perform better in board exams, while noting that teachers can prepare additional questions to improve student competency.
The document summarizes research on understanding charge transport in low dimensional semiconductor nanostructures embedded in an insulating matrix. Specifically, it examines current-voltage characteristics of germanium nanowire arrays in an alumina matrix as a function of temperature. Key findings include:
1) At room temperature, conduction follows Ohm's law at low voltages and Mott-Gurney's space charge limited current law at higher voltages.
2) With decreasing temperature, conduction transitions from a trap-free regime to an exponentially distributed trap regime.
3) Mobility decreases with decreasing temperature, and activation energy is extracted from an Arrhenius plot, found to be 85 meV at low temperatures and 301 meV
This document presents a novel stochastic approach for assessing the lightning performance of overhead transmission lines (OHLs). It combines systematic simulations using an accurate EMTP model of a 110 kV OHL with probability distribution functions obtained statistically. The probabilities of different outcomes, like the number of insulator string flashovers from a direct lightning strike, are calculated. These "stochastic lightning performance characteristics" provide a meaningful way to compare the lightning performance of different OHL configurations. The approach is demonstrated through simulations of a 110 kV line in Ireland that had experienced lightning issues.
Physics Sample Paper with General Instruction for Class - 12Learning Three Sixty
Learning 360 brings “Physics sample paper” for CLASS – 12. This document also carries 31 questions with solution of each given question for better understanding of the students. Download for free now; http://www.learning360.net/study_hub/1090-2/
Some Aspects of Stress Distribution and Effect of Voids Having Different Gase...IOSR Journals
1) The document analyzes the stress distribution and effect of voids with different gases in MV power cables through finite element modeling. It studies the electric field and temperature distribution within cable insulation containing voids.
2) Cylindrical voids are found to have higher electric stress than spherical or elliptical voids. Among gases, oxygen consumption during partial discharge causes greater temperature rise and faster breakdown than nitrogen.
3) The analysis examines factors like void shape, position, and size that influence stress distribution and partial discharge inception voltage. Nearer and larger voids have lower inception voltages. Oxygen consumption leads to uniform erosion and higher temperatures, making its effect greater than other gases.
This document discusses plane wave reflection from a media interface. It begins by introducing the concepts of reflection and transmission coefficients which describe how much of an incident wave is reflected or transmitted at a boundary. It then examines plane wave reflection at normal incidence, deriving expressions for the reflected and transmitted electric and magnetic fields in two lossy media. Boundary conditions requiring the tangential field components to be continuous are applied to obtain equations relating the reflection and transmission coefficients to the material properties on either side of the interface.
Semiconductors have electrical properties between conductors and insulators. They behave as insulators at low temperatures but conduct electricity at room temperature due to their small band gap. Doping semiconductors with impurities creates an excess of electrons or holes, making them n-type or p-type. A p-n junction is formed at the boundary between p-type and n-type semiconductors and allows current to flow in only one direction, making it useful for diodes. Diodes are used to convert alternating current to direct current and have many applications in electronics.
This document provides an introduction to basic electrical concepts including charge, current, voltage, power, energy, and circuit elements. It defines the international system of units used in electrical engineering. Key concepts covered include defining the ampere as the unit of current representing the flow of electric charge, defining voltage as the work required to move a unit of charge from one point to another, and defining power as the rate at which energy is transferred. Circuit analysis techniques are introduced for studying the behavior of electric circuits.
This document discusses electromagnetic field theory and computational electromagnetics. It introduces electromagnetic theory, which is divided into electrostatics, magnetostatics, and time-varying fields. Computational electromagnetics is presented as a way to numerically solve electromagnetic problems using computers. Different types of equation solvers are described, including integral equation solvers and differential equation solvers. General coordinate systems and transformations between coordinate systems are also covered.
The document discusses the theory of solids, specifically semiconductors, conductors, and insulators. It describes the energy band structure and forbidden energy gaps that determine whether a material is a semiconductor, conductor, or insulator. It also discusses PN junction diodes, their I-V characteristics, and applications in rectifiers. Transistors are also briefly introduced.
This document summarizes the key electrical properties of metals and semiconductors. It discusses Ohm's law and how electrical conductivity in metals is influenced by drift velocity and current density. It also explains how resistivity is related to temperature in metals. For semiconductors, it describes the band structure of insulators, metals and semiconductors and how conductivity varies with intrinsic carrier concentration and temperature in intrinsic semiconductors. It then discusses the effects of doping on carrier concentrations and conductivity in n-type and p-type extrinsic semiconductors. Finally, it provides an overview of compound semiconductors made of two or three elements.
This document provides a brief introduction to bioimpedance, which refers to the electrical properties of biological tissue measured when current flows through it. It discusses how resistance and capacitance are the two basic properties affecting bioimpedance. Resistance opposes the flow of current, while capacitance allows alternating but not direct current to pass through. When current passes through tissue, it encounters resistance in the extracellular space at low frequencies but both resistance and capacitance at higher frequencies as it can then enter cells. Cole-Cole plots are used to display how impedance changes with frequency based on the resistance and capacitance properties of tissue.
This chapter discusses electrical conduction processes in materials and semiconductor devices. It begins by describing conduction in metals, semiconductors, and doped semiconductors. Next, it covers the p-n junction, including the formation of a space-charge layer and drift and diffusion currents. The characteristics of the p-n junction and diode are then explained. The chapter concludes by discussing maximum power dissipation and voltage limitations in diodes due to avalanche and Zener breakdown.
This document discusses semiconductor materials and their properties. It explains that semiconductors have a conductivity between insulators and metals due to their band gap. The size of the band gap determines whether a material is a semiconductor or insulator. Doping semiconductors by adding impurities can increase or decrease the number of charge carriers, tuning the material's electronic properties. Metal contacts to semiconductors can form rectifying Schottky barriers or ohmic contacts depending on the barrier height and width. Schottky diodes use a Schottky barrier for rectification while ohmic contacts are used for signals in semiconductor devices.
This document provides an introduction to analog electronics and discusses key concepts related to semiconductors and diodes. It defines analog electronics as systems with continuously variable signals, as opposed to digital electronics which use discrete signals. Semiconductors are described as having electrical conductivity between conductors and insulators. The document discusses n-type and p-type semiconductors, the PN junction, and diode characteristics under forward and reverse bias. Diode models including the ideal diode model and equivalent circuit models are presented. Key diode parameters such as forward and reverse resistance are also summarized.
Electrical current, voltage, resistance, capacitance, and inductance are a few of the basic elements of electronics and radio. Apart from current, voltage, resistance, capacitance, and inductance, there are many other interesting elements to electronic technology. ... Use Electronics Notes to learn electronics online.
This document discusses semiconductor devices and materials. It begins by defining conductors, insulators, and semiconductors based on their conductivity ranges. Intrinsic semiconductors like silicon and germanium have low conductivity that can be increased by temperature. Extrinsic semiconductors are made by doping intrinsics with impurities to add charge carriers. N-type uses donors to add electrons, while P-type uses acceptors to add holes. When a semiconductor is doped with both types, a PN junction is formed with a depletion region and potential barrier. Semiconductor diodes consist of a PN junction that can control current flow. Common applications of semiconductors include transistors in electronics, solar cells,
This document discusses the formation and operation of p-n junction diodes. It describes three common methods for forming a p-n junction: alloying, diffusion, and vapor deposition. It explains key concepts such as the depletion region, barrier potential, drift and diffusion currents, and forward and reverse biasing. Forward biasing decreases the width of the depletion region, allowing majority carriers to flow more easily across the junction and conduct current.
Diploma sem 2 applied science physics-unit 3-chap-1 band theory of solidRai University
This document provides an overview of band theory of solids. It discusses key concepts such as effective mass of electrons, the concept of holes, and the energy band structure of conductors, semiconductors and insulators. It explains that conductors have overlapping valence and conduction bands, semiconductors have a small bandgap, and insulators have a large bandgap. The document also covers intrinsic and extrinsic semiconductors, the operation of p-n junction diodes under reverse and forward bias, and types of diodes such as simple diodes and Zener diodes.
Advancements of Semi conductors and Superconductorsadnanalvi051
explained what are semiconductors and superconductors and their uses. Also nowadays revolutions and advancements in semiconductors as superconductors. After reading these Slides one can easily understand about semiconductors and Superconductors, Nowadays our life is full of semiconductor usage.
Presentation report for Intrinsic & Extrinsic , N-type & P-type and Forward& ...Obaid ur Rehman
This document is a presentation report on intrinsic and extrinsic semiconductors, n-type and p-type semiconductors, and forward and reverse biasing. It was submitted by 4 students from the University of Lahore's Department of Physics. The 9-page report provides definitions and explanations of these key semiconductor concepts, including a brief history of semiconductors, intrinsic and extrinsic semiconductors, n-type and p-type doping, forward and reverse biasing of p-n junctions, and applications such as LEDs, photodiodes, and solar cells.
The document discusses a course on basic electronics at Matrusri Engineering College. It includes:
1. The course objectives are to understand the characteristics and design concepts of diodes, transistors, feedback amplifiers, oscillators, and operational amplifiers.
2. The course outcomes are for students to be able to analyze and design rectifier, regulator, amplifier, and oscillator circuits and understand the performance of transistors.
3. The first module will cover the characteristics of PN junctions, including half wave and full wave rectifiers, and diodes such as Zener diodes.
This document provides information on advancements in semiconductors and superconductors. It defines semiconductors and describes their intrinsic and extrinsic types. Applications of semiconductors include displays, RFID tags, and solar cells. Superconductors are materials that conduct electricity without resistance below a critical temperature. The document defines key terms related to superconductors like critical temperature and Meissner effect, and provides examples of superconducting materials like YBa2Cu307.
B.tech sem i engineering physics u ii chapter 1-band theory of solidRai University
This document provides an overview of band theory of solids. It discusses effective mass of electrons in solids, the concept of holes, and the energy band structure of conductors, semiconductors, and insulators. Intrinsic and extrinsic semiconductors are described, along with p-type and n-type materials. Simple diode and Zener diode operation is summarized, including forward and reverse bias conditions.
This document outlines the course objectives, outcomes, contents, and units for a Basic Electronics course at Matrusri Engineering College. The course aims to teach students about the characteristics, design concepts, and applications of diodes, transistors, feedback amplifiers, oscillators, and operational amplifiers. Specific topics covered include rectifier and regulator circuits, biasing of BJTs and FETs, oscillator design, logic gates, and data acquisition systems. One unit focuses on semiconductor materials and diode circuit design, while another covers Zener diodes, voltage regulators, and the construction and applications of cathode ray tubes in oscilloscopes.
Thermionic (vacuum tube) diodes and solid state (semiconductor) diodes were developed separately in the early 1900s as radio receiver detectors. Vacuum tube diodes were more commonly used in radios until the 1950s due to early semiconductor diodes being less stable. Semiconductor diodes are made from materials like silicon and germanium that have precise atomic structures that allow controlled current flow. A p-n junction is formed at the interface between p-type and n-type semiconductor materials and enables diode rectification properties. Diodes have various applications including rectification, clamping, clipping, and lighting.
This document provides an introduction to semiconductor devices and applications. It begins by discussing the basic structure of atoms and how solids can be classified as conductors, insulators, or semiconductors based on their electrical properties. The key concepts of energy bands and band gaps in semiconductors are introduced. The document then covers intrinsic and extrinsic semiconductors, PN junction diodes, their I-V characteristics, and applications such as rectification and voltage regulation using Zener diodes. Switching characteristics of diodes like recovery time are also discussed.
BASIC ELECTRONICS on physics for teaching grade 12JerryOgugo
This document provides an overview of basic electronics topics related to semiconductors. It discusses semiconductors and their charge carriers, how temperature affects semiconductors, types of semiconductors including n-type and p-type, types of impurities used for doping, the p-n junction diode, diode characteristics, applications of diodes, and advantages of p-n junction diodes over thermionic diodes. It also lists lesson contents, modes of conduction in semiconductors, effects of temperature, classification of materials, and differences between intrinsic and extrinsic semiconductors. Examples and classwork questions are provided at the end.
Semiconductors have properties between conductors and insulators due to their small energy band gap. Band theory explains the allowed energy levels for electrons in solids. Intrinsic semiconductors have few charge carriers that are generated thermally, while extrinsic semiconductors have impurities that generate majority carriers. The Hall effect demonstrates the behavior of charge carriers in a magnetic field and can determine carrier type and concentration. Semiconductors are used widely in electronic devices like diodes, transistors, sensors and solar cells due to their small size, low power needs, and long lifespan.
Transistors and integrated circuits are important components in electronics. A transistor is a semiconductor device with three electrical contacts that can be used as an amplifier, detector, or switch. An integrated circuit is a circuit composed of transistors, resistors, and capacitors constructed on a single semiconductor chip, where the components are interconnected to perform a given function. A bipolar junction transistor consists of a three-layer sandwich of doped semiconductor materials (either PNP or NPN) where a small base current controls a larger collector current flowing between the emitter and collector. Integrated circuits allow many transistors to be packed onto a single chip to construct more complex circuits.
This document discusses semiconductors and diodes. It describes how semiconductors have electrical properties between conductors and insulators. Holes and electrons are charge carriers in semiconductors. The band theory of semiconductors involves energy bands and band gaps. Semiconductors have a conduction band and a valence band. Intrinsic semiconductors use a single element, while extrinsic semiconductors are doped with impurities. PN junction diodes are formed from a P-type and N-type semiconductor and have different characteristics under forward, reverse, and zero bias conditions.
The document discusses semiconductor devices and their characteristics. It covers topics like energy bands in semiconductors, carrier concentration, drift and diffusion current, the Hall effect, and PN junction diodes. Specifically, it describes direct and indirect bandgap semiconductors, how carrier concentration is determined in intrinsic and extrinsic semiconductors, and how drift current occurs under an applied electric field while diffusion current moves charges from high to low concentration regions. It also explains the Hall effect where a voltage develops perpendicular to the current and magnetic field.
Similar to Electrical Measurements for Semiconducting Devices (20)
This document provides a résumé for Dr. Yogesh P. Patil. It outlines his educational background, work experience, research interests, publications, projects, and administrative responsibilities. Some key details include:
- He holds a Ph.D. in Polymer Technology and works as an Associate Professor of Chemistry.
- His research interests include materials chemistry with a focus on polymers, fuels, and water treatment.
- He has over 20 years of experience in teaching, research, and administrative roles and has numerous publications, projects, and awards.
- His current responsibilities include teaching engineering chemistry, managing research projects, and administrative coordination as Head of the Department.
The document discusses the role of chemistry in engineering. It provides examples of how chemistry is used in various applications such as manufacturing fertilizers, pharmaceutical drugs, synthetic fibers, fuels, and metals. Chemistry is also used to understand biological processes. Quantum dots are discussed as a material with applications in bioimaging, drug delivery, and cancer therapies due to their optical and electrical properties. Carbon quantum dots and graphene quantum dots are also mentioned for their use in water treatment and membrane technologies due to properties like small size and functional groups. The document concludes by discussing how Samsung and LG are moving away from LCD screens in favor of quantum dot and OLED display technologies.
The document discusses the role of chemistry in various engineering applications. It provides examples of how chemistry is used in solar cells, magnetically elevated trains, and sensor technology. Quantum dots and their uses are also explained in detail. The document highlights how chemistry is essential to materials processing and manufacturing across many industries including energy, transportation, and electronics.
The document discusses biofuels, including their need, benefits, and analysis. It provides an introduction to biofuels and their role in reducing carbon emissions. It then discusses the need for biofuels in terms of their ease of use in vehicles, ability to provide energy security, potential for economic development, and ability to reduce greenhouse gas emissions. However, biofuels also face objections regarding their economic viability and environmental impacts. The document concludes by discussing life cycle analysis of biofuels and perspectives on biodiesel.
The processing of cd se polymer nanocompositesYogesh Patil
The document describes a method for synthesizing CdSe nanoparticles within polymer matrices using organometallic precursors. Specifically, it details:
1) CdSe nanoparticles were synthesized in situ within poly(vinyl alcohol) (PVA) and polymethylmethacrylate (PMMA) polymers by reacting cadmium acetate and 1,2,3-selenadiazole, which serves as the selenium source.
2) UV-vis spectroscopy showed blue shifts in the absorption spectra of the CdSe/polymer nanocomposites compared to bulk CdSe, indicating the formation of quantum-sized CdSe nanoparticles.
3) Photoluminescence spectroscopy showed an emission band at 530 nm
This document is a resume for Dr. Yogesh P. Patil summarizing his educational and professional experience. It lists his educational qualifications including a Ph.D. in Chemistry from North Maharashtra University. It details his work experience as a lecturer and research associate, and lists his areas of research interest and publications. The resume provides contact information and highlights his teaching experience, publications, grants received, and administrative roles held.
The document discusses the history and development of chemistry from ancient times to the modern era. It describes how early alchemists studied chemistry under the goals of discovering the philosopher's stone and divine solution. Several important 18th century scientists are highlighted for their contributions, including Cavendish who discovered the mass of the Earth, Lavoisier who established the modern system of chemical nomenclature, and Faraday who invented the electric motor. The development of technology during the Industrial Revolution and advances in fields like physics, medicine, and computers in the 20th century are also summarized.
1. The document discusses the chemistry behind feelings of love, lust, and attraction. Key chemicals involved include dopamine, norepinephrine, oxytocin, vasopressin, phenylethylamine, testosterone, and estrogen.
2. These chemicals help drive the three stages of love - lust, attraction, and attachment. Lust is driven by sex hormones, attraction by dopamine, norepinephrine and serotonin, and attachment by oxytocin and vasopressin which facilitate bonding.
3. Keeping love alive involves triggering these same chemical responses through novelty, touch, and intimacy to sustain romantic love over the long term.
This document compares the synthesis of oximes using traditional chemical methods versus ultrasonic irradiation. Oximes are important organic intermediates. The traditional method involves refluxing carbonyl compounds with hydroxylamine hydrochloride solution in ethanol as a solvent, taking 50-60 minutes and yielding 70-75%. Using ultrasonic irradiation, the same oximes were synthesized without solvent in 10-20 minutes, yielding 75-85%, which is higher than the traditional method. Yields were lowest for benzophenone oxime due to electron donation by phenyl groups decreasing carbonyl reactivity. Yields were highest for 4-chlorobenzaldehyde oxime due to electron withdrawal increasing reactivity. Thin layer chromatography confirmed the oximes produced
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Thinking of getting a dog? Be aware that breeds like Pit Bulls, Rottweilers, and German Shepherds can be loyal and dangerous. Proper training and socialization are crucial to preventing aggressive behaviors. Ensure safety by understanding their needs and always supervising interactions. Stay safe, and enjoy your furry friends!
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Electrical Measurements for Semiconducting Devices
1. International Journal of Science and Research (IJSR)
ISSN (Online): 2319-7064
Index Copernicus Value (2013): 6.14 | Impact Factor (2014): 5.611
Volume 5 Issue 3, March 2016
www.ijsr.net
Licensed Under Creative Commons Attribution CC BY
Electrical Measurements for Semiconducting
Devices
Vishakha N. Dhanwate1
, Yogesh P. Patil2
Department of Engineering Sciences, AISSMS’s Institute of Information Technology Pune, MH, India
Abstract: In the last decade the research of semiconducting compounds reached to a particular level having as a goal the elaboration
for the high efficiency solar cells of low cost. Functioning of a pn-junction is based on heat dependence of the current-voltage
characteristics suggests boundary recombination as dominating transport mechanism. These junctions are appropriate for photovoltaic
light conversion and for the growth of solar cells in superstrate configuration. In this Informative paper we have discussed basic of
electrical measurements through which it is possible to deal with Current-Voltage Characteristics (I-V) and Capaciatnce-Viltage (C-V)
Characteristics’ for solar cell applications.
Keywords: Semiconductors, Heterojunctions, Photovoltaic’s, I-V, C-V characteristics
1. Introduction
The current-voltage (I-V) characteristics are based on
relations between the electric current passing through a
circuit and the corresponding potential (voltage) across it,
where electrical current is a measure of the amount of
electrical charge transferred per unit time. It represents the
flow of electrons through a conductive material and Voltage
is the electric potential energy per unit charge. If a unit of
electrical charge were placed in a location, the voltage
indicates the potential energy of it at that point. In other
words, it is a measurement of the energy contained within an
electric field, or an electric circuit, at a given point whereas
resistance is the opposition to the flow of electric current by
the component.
An I-V characteristic is the method of electrical
measurements especially for semiconducting devices. There
are two types of semiconductors,
Intrinsic semiconductor: It is an undoped or pure
semiconductor without any significant doping.
Extrinsic semiconductor: It is a semiconductor in which
doping is introduced, due to that it shows different electrical
properties than the intrinsic (pure) semiconductor.
There are two types of extrinsic semiconductor, p-type
semiconductor: p-type semiconductors have a larger hole
concentration than electron concentration. The phrase 'p-
type' refers to the positive charge of the hole. In p-type
semiconductors, holes are the majority carriers and electrons
are the minority carriers. P-type semiconductors are created
by doping an intrinsic semiconductor with acceptor
impurities.
n-type semiconductor: n-type semiconductor have a larger
electron concentration than hole concentration. The phrase
'n-type' comes from the negative charge of the electron. In n-
type semiconductors, electrons are the majority carriers and
holes are the minority carriers. N-type semiconductors are
created by doping an intrinsic semiconductor with donor
impurities [1].
Figure 1: The energy band diagram for a metal and n-type semiconductor rectifying junction a) before contact b) after contact
Paper ID: NOV161796 669
2. International Journal of Science and Research (IJSR)
ISSN (Online): 2319-7064
Index Copernicus Value (2013): 6.14 | Impact Factor (2014): 5.611
Volume 5 Issue 3, March 2016
www.ijsr.net
Licensed Under Creative Commons Attribution CC BY
A p–n junction is a interface between p-type and n-type of
semiconductor material. A p–n junction is elementary
"fundamental building blocks" of most semiconductor
electronic devices such as diodes.
Metal–semiconductor (M–S) junction is a type of junction in
which a metal comes in close contact with a semiconductor
material. It is the oldest practical semiconductor device. M–
S junctions can either be rectifying or non-rectifying. The
rectifying metal–semiconductor junction forms a Schottky
barrier, making a device known as a Schottky diode, while
the non-rectifying junction is called an ohmic contact.
2. Schottky junction
When a metal and a semiconductor with therefore different
Fermi energy levels are brought in contact with each other,
the Fermi energy of each material will line up to a common
level. In case on a n-type semiconductor the Fermi energy of
the semiconductor is larger than the Fermi energy of the
metal. Because there are many empty energy states in the
metal, electrons with sufficient energy will flow into the
metal taking the energy state. By leaving the semiconductor
there will be unfilled energy states left in the semiconductor.
Moreover, because a contact between the two different
materials can never be ideal, the presence of chemical
defects or broken bonds will cause large numbers of unfilled
so called surface states.
These Free states will be filled by electrons from the
semiconductor bulk. This provides a positive charge under
the junction and a depletion region is formed. During this
process the valence and conduction band is bent by the
positive depletion charge preventing more electrons to take
metal or surface states. Because the number of unfilled
surface states is high, the metal side is assumed to be
constant.
If a metal work function is larger than a semiconductor
electron affinity , therefore contacting metal to the
semiconductor leads to electron flow from the
semiconductor to the metal as a prerequisite of Fermi levels
alignment and thermal equilibrium. The remaining
positively charged atoms in the semiconductor part create a
space charge region. Thus electron flows from
semiconductor to metal see a barrier of height
space charge region. Thus electron flows from
known
as Schottky barrier.
3. Ohmic Contacts
An ohmic contact is a non-rectifying junction- a region in a
semiconductor device that has been prepared so that the
current-voltage (I-V) curve of the region is linear and
symmetric. Usually it is a metal-semiconductor junction
between a metal and semiconductor material. In
semiconductor device fabrication (integrated circuit
packaging), to make an ohmic contact, the contact region is
doped, creating an extrinsic semiconductor to ensure the
type of contact wanted (usually an n+ doped contact for an
n-type silicon wafer and aluminum wires).
In this type of contacts, after thermal equilibrium, this
occurs when electrons flows from the metal to the
semiconductor lower energy levels. These electrons flow
back into the metal part if a positive bias in the metal part
was applied, and they will feel no barrier. Applying negative
bias forces electrons to flow from metal to semiconductor
seeing a very small barrier.
Figure 2: Energy band diagram for a metal –n- type semiconductor non rectifying junction a) before contact b) after contact.
The improvement in current indicates the decrease in grain
boundaries and defects [3]. Defect enhances recombination
process. More defects mean more space charge
combinations. If there were no defects present, the total
diode current would be diffusion current and n is equal to 1;
this will be ideal diode case [2]. More defects drives n up to
2.
)1(
1
slopenkT
q
n
n is ideality factor, q is Charge on electron, k is Boltzmann
constant, Absolute temperature.
Schottky barrier diode characteristics can be expressed as,
Paper ID: NOV161796 670
3. International Journal of Science and Research (IJSR)
ISSN (Online): 2319-7064
Index Copernicus Value (2013): 6.14 | Impact Factor (2014): 5.611
Volume 5 Issue 3, March 2016
www.ijsr.net
Licensed Under Creative Commons Attribution CC BY
)2(0
eI
nkT
qv
I
I0 is reverse saturation current which is y-intercept of graph
ln(I) verses V.
Barrier potential can be calculated by,
)3(ln
0
2*
I
TA
q
kT
B
ϕB is barrier potential, A*
is Effective Richardson constant
which is calculated by,
)4(
4
0
*2
*
I
mk
A
q
h is Planck’s constant , m*
is effective mass. m0 is rest mass
[2].
Capacitance-Voltage (C-V) measurement is widely used to
determine semiconductor parameters, particularly in
MOSCAP and MOSFET structures. However, other types of
semiconductor and technologies also can be characterized
with C-V measurements, including bipolar junction
transistors, JFETs, III-V compound
Devices, photovoltaic cells, organic thin film transistor
(TFT) displays, photodiodes, and carbon nanotubes.
Figure 3: Metal-Insulator- semiconductor (MIS) diode
The metal-insulator semiconductor (MIS) diode is the most
constructive in the study of semiconductor surfaces. This
system has been broadly studied for the reason that it is in a
straight line related to the most planner device and
integrated circuits. The MIS structure in fig 3, where d is
thickness of the insulator and V is the applied voltage on the
metal field plate. We use the convention that the voltage V is
positive when the metal plate is positively biased with
respect to ohmic contact. When the MIS diode is biased
with positive or negative voltages, essentially three cases
may exist at the semiconductor surface [4].
Firstly the “accumulation” region, when the small negative
voltage is applied, the band bends upward, and the majority
carriers are depleted in second region called “depletion”.
When a positive voltage (v>0) is applied to metal plate, the
top of the valance band bends downward and closer to Fermi
level. For an ideal MIS diode, no current flows in the device.
So, the Fermi level remains stable in the semiconductors.
Since the carrier density depends exponentially on the
energy difference (Ef - Ev), this band bending causes an
accumulation of majority carriers (electrons) close to the
semiconductor surface. When the superior negative voltage
is applied, the band bend even more upward so that the
intrinsic level Ei at the surface crosses over the Fermi level
Ef. At this point the number of holes, the surface is thus
inverted, and this is theinversion case.
The capacitance-voltage measurement is usually carried out
in order to estimate doping concentration of the
semiconductor and the flat band voltage of the Schottky
diode. The C-V characteristics of all the films involved
distinct inversion, depletion, and accumulation regions,
during the CV measurement the device is swept from
accumulation to inversion. Semiconductor doping
concentration can be calculated by the formula [5].
(5)------------------
)
)1(
(q
2
2
2
dV
c
d
A
N A
NA is doping concentration of semiconducting material, q is
charge on electron, ε is permittivity of the material and
dV
c
d )1( 2
slope is obtained from graph 1/C2
verses V. Flat
band potential is used as characteristics potential of
individual semiconductor electrodes in the same way as the
potential of zero charge is used for metal electrodes. Flat
band potential is determined by extrapolation to C = 0 [4].
4. Conclusion
To improve the efficiency of solar cell, we have to enhance
the electrical properties of the material. For that electrical
properties of heterojunctions involving wide gap n-type and
the p-type semiconductor materials. With the above given
formulas it is possible to find ideality factor and barrier
potential by using I-V characteristics. Same way flat band
potential and carrier concentration can be obtained with C-V
measurements. These are said to be primary testing for
efficiency of device.
References
[1] Mehta V.K, Mehta Shalu, Introduction to solid state
Physics, Seventh edition, John Wiley & Sons Inc, India
(2009).
[2] Sze S. m, Semiconductor devices, revised edition, John
Wiley & Sons inc, UK (2009).
[3] Dhanwate V.N and Chaure N.B, Effect of growth
potential on the electrodeposition of CIS thin films,
Applied Nanoscience, 3 (2013) 1-5.
[4] Streetman B.G, Sanjay Kumar Banerjee, Sixth edition,
Solid state electronic devices, Pearson prentice Hall,
USA (2006).
[5] Sze S.M. Physics of semiconductor devices, Second
edition, John Wiley & Sons Inc, UK (1981).
Paper ID: NOV161796 671