1 EXTRINSIC SEMICONDUCTOR In an extrinsic semiconducting material, the charge carriers originate from impurity atoms added to the original material is called impurity [or] extrinsic semiconductor. This Semiconductor obtained by doping TRIVALENT and PENTAVALENT impurites in a TETRAVALENT semiconductor. The electrical conductivity of pure semiconductors may be changed even with the addition of few amount of impurities.
2 DOPING The method of adding impurities to a pure semiconductor is known as DOPING, and the impurity added is called the dopping agent(ex-ar,sb,p,ge and Al). The addition of impurity would increases the no. of free electrons and holes in a semiconductor and hence increases its conductivity. SORTS OF SEMICONDUCTOR according to ADDITION OF IMPURITIES n-type semiconductor p-type semiconductor
3 N type semiconductor When pentavalent impurity is added to the intrinsic semiconductors, n type semi conductors are formed. E c E d Conduction band E v E g Valence band Donors levels occupied n - type semiconductor At T = 0K
4 When small amounts of pentavalent impurity such as phosphorous are added during crystal formation, the impurity atoms lock into the crystal lattice[ see above Fig). Consider a silicon crystal which is doped with a fifth column element such as P, As or Sb. Four of the five electrons in the outermost orbital of the phosphorus atom take part in the tetrahedral bonding with the four silicon neighbours. The fifth electron cannot take part in the discrete covalent bonding. It is loosely bound to the parent atom.
5 It is possible to calculate an orbit for the fifth electron assuming that it revolves around the positively charged phosphorus ion, in the same way as for the 1s electron around the hydrogen nucleus. The electron of the phosphorus atom is moving in the electric field of the silicon crystal and not in free space, as is the case in the hydrogen atom. This brings in the dielectric constant of the crystal into the orbital calculations, and the radius of the electron orbit here turns out to be very large, about 80 Å, as against 0.5 Å for the hydrogen orbit. Such a large orbit evidently means that the fifth electron is almost free and is at an energy level close to the conduction band.
6 At 0 K, the electronic system is in its lowest energy state, all the valence electron will be in the valence band and all the phosphorous atoms will be un-ionised. The energy levels of the donor atoms are very close to the conduction band. In the energy level diagram, the energy level of the fifth electron is called donor level. The donor level is so close to the bottom of the conduction band. Most of the donor level electrons are excited into the conduction band at room temperature and become majority charge carriers.
7 Conduction band Conduction band E c E d E c E d E v E g Valence band Donors levels ionised E v E g Valence band Donors levels ionised At T > 0K At T = 300K If the thermal energy is sufficiently high, in addition to the ionization of donor impurity atoms, breaking of covalent bonds may also occur thereby giving rise to generation of electron hole pair.
8 P -Type Semiconductor When trivalent impurity is added to intrinsic semiconductor, P type semi conductors are formed. Al has three electrons in the outer orbital. While substituting for silicon in the crystal, it needs an extraelectron to complete the tetrahedral arrangement of bonds around it.
9 The extra electron can come only from one of the neighboring silicon atoms, thereby creating a vacant electron site (hole) on the silicon. The aluminum atom with the extra electron becomes a negative charge and the hole with a positive charge can be considered to resolve around the aluminum atom. E c Conduction band E g E a E v Valence band p - type semiconductor At T = 0K
10 Since the trivalent impurity accepts an electron, the energy level of this impurity atom is called acceptor level. This acceptor level lies just above the valence bond. Even at relatively low temperatures, these acceptor atoms get ionized taking electrons from valence bond and thus giving to holes in the valence bond for conduction. Due to ionization of acceptor atoms, only holes and no electrons are created.
11 If the temperature is sufficiently high, in addition to the above process, electron-hole pairs are generated due to the breaking of covalent bonds. Thus holes are more in number than electrons and hence holes are majority carriers and electrons are minority carriers E c Conduction band E g Acceptors have accepted electrons from valence band E a E v Valence band (a) At T > 0K (b) At T = 300K
12 Hall Effect When a piece of conductor (metal or semi conductor) carrying a current is placed in a transverse magnetic field, an electric field is produced inside the conductor in a direction normal to both the current and the magnetic field. This phenomenon is known as the Hall Effect and the generated voltage is called the Hall voltage. Y G B I D F O E C X Z A B E H Hall effect
13 Consider a conventional current flow through the strip along OX and a magnetic field of induction B is applied along axis OY. Case I: If the Material is N-Type Semi Conductor (or) Metal If the strip is made up of metal or N-type semiconductor, the charge carriers in the strip will be electrons. As conventional current flows along OX, the electrons must be moving along XO. If the velocity of the electrons is `v and charge of the electrons is ` e, the force on the electrons due to the magnetic field
14 F = Bev, which acts along OZ. This causes the electrons to be deflected and the electrons accumulate at the face ABEF. Face ABEF will become negative and the face OCDG becomes positive. A potential difference is established across faces ABEF and OCDG, causing a field E H. Y B v B Z F A Force on electron G O F Hall effect for n type semiconductor B E C D X I
15 This field gives rise to a force of ` ee H on the electrons in the opposite direction. (i.e, in the negative Z direction) At equilibrium, ee H = Be (or) E H = B If J is the current density, then, J = ne where `n is the concentration of current carriers. v = J ne Substitute the value of ` in eqn E H = BJ ne
16 The Hall Effect is described by means of the Hall coefficient `R H in terms of current density `J by the relation, E H = R H BJ (or) R H = E H / BJ BJ 1 R H nebj ne All the three quantities E H, J and B are measurable, the Hall coefficient R H and hence the carrier density `n can be found out.
17 Case (ii) If the material is a P-type semi conductor If the strip is a P-type semiconductor, the charge carriers in the strip will be holes. The holes will constitute current in the direction of conventional current. Holes move along the direction of the conventional Y current itself along ox Z F A Force on hole G O B F Hall effect for p type semiconductor B B E v C D X I
18 If `e is the charge of the hole, the force experienced by the holes due to magnetic field is, F = Be, which acts along OZ. This causes the holes to accumulate on the face ABEF making it positive, and leaving the face OCDG as negative. P-type semiconductor, R H = 1/pe, where p = the density of holes.
19 Determination of Hall coefficient The Hall coefficient is determined by measuring the Hall voltage that generates the Hall field. If `w is the width of the sample across which the Hall voltage is measured, then E H = V H / w We know that, R H = E H / BJ Substituting the value of E H in the above eqn RH = V H / wbj (or) V H = R H wbj
20 If the thickness of the sample is `t, the its cross sectional area A = wt, and the current density, J= I A I wt V H = Substitute the value of `J R H w.b.i wt R H t I B = (or) R H = V H t IB V H will be opposite in sign for P and N type semiconductors.
21 A rectangular slab of the given material having thickness `t and width `w is taken. A current of `I amperes is passed through this sample by connecting it to a battery, `Ba. The sample is placed between two pole pieces of an electromagnet such that the field `B is perpendicular to I Y G B I D F t O E w C X V H Z A B Ba A Rh
22 The hall voltage `V H is then measured by placing two probes at the two side faces of the slab. If the magnetic flux density is `B and `V H is the hall voltage, then the Hall coefficient, Y B G I D F t O E w C X V H Z A B Ba A Rh Experimental setup for the measurement of Hall voltage
23 R H = V H t / IB (m 3 /coulomb) For n-type material, n = ne e (or) H n n e R. ne For p-type material, p = p e h (or) H p p h R. pe
24 Applications of Hall effect (1) Determination of N-type of semiconductor For a N-type semiconductor, the Hall coefficient is negative whereas for a P-type semiconductor, it is positive. Thus from the direction of the Hall voltage developed, one can find out the type of semiconductor. (2) Calculation of carrier concentration Once Hall coefficient R H is measured, the carrier concentration can be obtained, n 1 er 1 ( or ) p H er H
25 (3)Determination of mobility We know that, conductivity, n = n e e (or) p Also, P = p e h (or) n p. RH Thus by measuring ` and R H, can be calculated. (4) Measurement of magnetic flux density. Using a semiconductor sample of known `R H, the magnetic flux density can be deduced from, R H = B pe V R H H t I
26 DILUTE MAGNETIC SEMICONDUCTORS Introduction Integrated circuits and high-frequency devices made of semiconductors, used for information processing and communications, have had great success using the charge of electrons in semiconductors.
27 Mass storage of information indispensable for information technology is carried out by magnetic recording (hard disks, magnetic tapes, magneto optical disks) using spin of electrons in ferromagnetic materials. Dilute or diluted magnetic semiconductors (DMS) also referred to as semi magnetic semiconductors, are alloys whose lattices are made up in part of substitutional magnetic atoms. DMS= Semiconductors with dilute concentration of magnetic dopants.
28 The most important feature of these materials is carrier mediated magnetism which can be easily controlled with voltage. The advantage is that, unlike the conventional magnets, DMS are compatible with semiconductors and can be used as efficient sources for spin injection. Three types of semiconductors: (A) a magnetic semiconductor(e.g. some spinels), in which a periodic array of magnetic element is present, (B) a dilute magnetic semiconductor(e.g. (GaMn)As,(InMn)P, ZnCoO etc), an alloy between nonmagnetic semiconductor and magnetic element and (C) a non-magnetic semiconductor(e.g. GaAs, InP, Cu2O, NiO etc), which contains no magnetic ions.
29 Materials The most common SMSC are II-VI compounds (like CdTe, ZnSe, CdSe, CdS, etc.), with transition metal ions (e.g. Mn, Fe or Co) substituting their original cations. There are also materials based on IV-VI (e.g. PbTe, SnTe) and recently III-V (e.g. GaAs, InSb) crystals. The wide variety of both host crystals and magnetic atoms provides materials which range from wide gap to zero gap semiconductors, and which reveal many different types of magnetic interaction. Formation of DMS
30 Several of the properties of these materials may be tuned by changing the concentration of the magnetic ions. The most relevant feature of DMS, is the coexistence and interaction of two different electronic sub systems: delocalized conduction (s-type) and valence (p-type) band electrons and localized (d or f-type) electrons of magnetic ions. In particular the spd exchange interaction leads to strong band splitting, which result in giant magneto optical effects.
31 The most studied III-V DMS system is Ga x Mn 1-x As with x up to The solubility limit of magnetic elements in III-V semiconductors is very low, but in order to have ferromagnetism in DMS, a sizable amount of magnetic ions are needed. This can only be accomplished by means of nonequilibrium crystal growth techniques, such as low temperature molecular beam epitaxy (MBE). The upper concentration limit of magnetic ions is around 10 %.
32 The highest conclusively reported Tc of DMS is around 110 K for 5 % doped GaAs. It is of great technological importance to find DMS systems with Tc above room temperature, before one attempts to make a DMS based device. Applications Diluted magnetic semiconductors (DMS) are expected to play an role in interdisciplinary materials science and future electronics because charge and spin degrees of freedom accommodated into a single material exhibits interesting magnetic, magneto-optical, magnetoelectronic and other properties.
33 It is expected that magnetoelectronic important chips will be used in quantum computers. An inherent advantage of magnetoelectronics over electronics is the fact that magnet tend to stay magnetized for long. Hence this arises interest in industries to replace the semiconductor-based components of computer with magnetic ones, starting from RAM. These DMS materials are very attractive for integration of photonic (light-emitting diodes), electronic (field effect transistors), and magnetic (memory) devices on a single substrate.
34 Some important application areas of DMS are listed below. Photonics plus spintronics (Spin+electronics = Spintronics) Improved spin transistor Transistors spin toward quantum computing Magnetic spins to store quantum information Microscope to view magnetism at atomic level
35 Ballistic magneto resistance Missile guidance Fast accurate position and motion sensing of mechanical components in precision aengineering and in robotics In automotive sensors
36 Importance of DMS based devices Information is stored (written) into spins as a particular spin orientation (up or down) The spins, being attached to mobile electrons, carry the information along a conductor The information can be stored or is read at a terminal. Spintronics devices are attractive for memory storage and magnetic sensors applications
37 Spin-based electronics promises a radical alternative to charge-based electronics, namely the possibility of logic operations with much lower power consumption than equivalent charge-based logic operations
Diluted Magnetic Semiconductor (DMS) 1 Properties of electron Useful! Charge Electron Spin? Mass 2 Schematic of a Spinning & Revolving Particle Spinning Revolution 3 Introduction Electronics Industry Uses
Semiconductors 1. Explain different types of semiconductors in detail with necessary bond diagrams. There are two types of semi conductors. 1. Intrinsic semiconductors 2. Extrinsic semiconductors Intrinsic
EE 446/646 Photovoltaic Devices I Y. Baghzouz What is Photovoltaics? First used in about 1890, the word has two parts: photo, derived from the Greek word for light, volt, relating to electricity pioneer
Introduction A semiconductor is a material that has a resistivity lies between that of a conductor and an insulator. The conductivity of a semiconductor material can be varied under an external electrical
EECS130 Integrated Circuit Devices Professor Ali Javey 8/30/2007 Semiconductor Fundamentals Lecture 2 Read: Chapters 1 and 2 Last Lecture: Energy Band Diagram Conduction band E c E g Band gap E v Valence
Lecture (02) PN Junctions and Diodes By: Dr. Ahmed ElShafee ١ I Agenda N type, P type semiconductors N Type Semiconductor P Type Semiconductor PN junction Energy Diagrams of the PN Junction and Depletion
Conductivity and Semi-Conductors J = current density = I/A E = Electric field intensity = V/l where l is the distance between two points Metals: Semiconductors: Many Polymers and Glasses 1 Electrical Conduction
EE495/695 Introduction to Semiconductors I Y. Baghzouz ECE Department UNLV Introduction Solar cells have always been aligned closely with other electronic devices. We will cover the basic aspects of semiconductor
electronics fundamentals circuits, devices, and applications THOMAS L. FLOYD DAVID M. BUCHLA Lesson 1: Diodes and Applications Semiconductors Figure 1-1 The Bohr model of an atom showing electrons in orbits
Today From Last Time Important new Quantum Mechanical Concepts Indistinguishability: Symmetries of the wavefunction: Symmetric and Antisymmetric Pauli exclusion principle: only one fermion per state Spin
SEMICONDUCTORS Conductivity lies between conductors and insulators The flow of charge in a metal results from the movement of electrons Electros are negatively charged particles (q=1.60x10-19 C ) The outermost
Concept of Core Conductivity of conductor and semiconductor can also be explained by concept of Core. Core: Core is a part of an atom other than its valence electrons. Core consists of all inner shells
1. What is intrinsic If a semiconductor is sufficiently pure, then it is known as intrinsic semiconductor. ex:: pure Ge, pure Si 2. Mention the expression for intrinsic carrier concentration of intrinsic
ECE 250 Electronic Devices 1 ECE 250 Electronic Device Modeling ECE 250 Electronic Devices 2 Introduction to Semiconductor Physics You should really take a semiconductor device physics course. We can only
Advantages / Disadvantages of semiconductor detectors Semiconductor detectors have a high density (compared to gas detector) large energy loss in a short distance diffusion effect is smaller than in gas
Being virtually killed by a virtual laser in a virtual space is just as effective as the real thing, because you are as dead as you think you are. -Douglas Adams, Mostly Harmless David J. Starling Penn
5 Feb 14 Semi.1 SEMICONDUCTOR BEHAVIOR AND THE HALL EFFECT The object of this experiment is to study various properties of n- and p-doped germanium crystals. The temperature dependence of the electrical
EE 5211 Analog Integrated Circuit Design Hua Tang Fall 2012 Today s topic: 1. Introduction to Analog IC 2. IC Manufacturing (Chapter 2) Introduction What is Integrated Circuit (IC) vs discrete circuits?
Electrical Properties Electrical Conduction R Ohm s law V = IR I l Area, A V where I is current (Ampere), V is voltage (Volts) and R is the resistance (Ohms or ) of the conductor Resistivity Resistivity,
3.1 Introduction to Semiconductors Y. Baghzouz ECE Department UNLV Introduction In this lecture, we will cover the basic aspects of semiconductor materials, and the physical mechanisms which are at the
Lecture 7: Extrinsic semiconductors - Fermi level Contents 1 Dopant materials 1 2 E F in extrinsic semiconductors 5 3 Temperature dependence of carrier concentration 6 3.1 Low temperature regime (T < T
Crystal Properties Crystal Lattices: Periodic arrangement of atoms Repeated unit cells (solid-state) Stuffing atoms into unit cells Determine mechanical & electrical properties High performance, high current
Diodes EE223 Digital & Analogue Electronics Derek Molloy 2012/2013 Derek.Molloy@dcu.ie Diodes: A Semiconductor? Conductors Such as copper, aluminium have a cloud of free electrons weak bound valence electrons
Chapter 4: Bonding in Solids and Electronic Properties Free electron theory Consider free electrons in a metal an electron gas. regards a metal as a box in which electrons are free to move. assumes nuclei
5. Semiconductors and P-N junction Thomas Zimmer, University of Bordeaux, France Summary Learning Outcomes... 2 Physical background of semiconductors... 2 The silicon crystal... 2 The energy bands... 3
Semiconductor Devices and Circuits Fall 2003 Midterm Exam Instructor: Dr. Dietmar Knipp, Professor of Electrical Engineering Name: Mat. -Nr.: Guidelines: Duration of the Midterm: 1 hour The exam is a closed
CHAPTER 1 Physical Properties of Elements and Semiconductors 1.1 Introduction Semiconductors constitute a large class of substances which have resistivities lying between those of insulators and conductors.
Research Highlights Dilute magnetic semiconductors and Spintronics Spintronics is a branch of electronics emerged from the dilute magnetic semiconductor in an aspect of utilization of the spin in addition
Romanian Reports in Physics, Vol. 62, No. 1, P. 115 120, 2010 SIMULATIONS ON DILUTE MAGNETIC SEMICONDUCTOR PROPERTIES M. NEGOITA, E. A. PATROI, C. V. ONICA National Institute for Research and Development
Microscopic Ohm s Law Outline Semiconductor Review Electron Scattering and Effective Mass Microscopic Derivation of Ohm s Law 1 TRUE / FALSE 1. Judging from the filled bands, material A is an insulator.
The German University in Cairo th Electronics 5 Semester Faculty of Information Engineering & Technology Semiconductors (Elct 503) Electronics Department Fall 2014 Problem Set 3 1- a) Find the resistivity
Electronic Properties of Lead Telluride Quantum Wells Liza Mulder Smith College 2013 NSF/REU Program Physics Department, University of Notre Dame Advisors: Profs. Jacek Furdyna, Malgorzata Dobrowolska,
1 V. Semiconductor Detectors V.1. Principles Semiconductor Detectors are Ionization Chambers Detection volume with electric field Energy deposited positive and negative charge pairs Charges move in field
R measurements (resistivity, magnetoresistance, Hall). 590B Makariy A. Tanatar April 18, 2014 Resistivity Typical resistivity temperature dependence: metals, semiconductors Magnetic scattering Resistivities
Determination of properties in semiconductor materials by applying Matlab Carlos Figueroa. 1, Raúl Riera A. 2 1 Departamento de Ingeniería Industrial. Universidad de Sonora A.P. 5-088, Hermosillo, Sonora.
Semiconductors and its Properties Anurag Srivastava Basic characteristics of semiconductors Something about the history: 1833 M. Faraday: For AgS decreasing ρ with increasing T 1873 W. Smith: Photoconductivity
Semiconductors and Optoelectronics Advanced Physics Lab, PHYS 3600 Don Heiman, Northeastern University, 2017 Today Semiconductors Acoustics Tomorrow Come to CH325 Exercises Tours Semiconductors and Optoelectronics
BASIC ELECTRONICS Subject Code: ELN-15/5 IA marks: 5 Hours per week : 04 Exam Hours 03 Total Hrs: 5 Exam Marks: 100 CHAPTER 1 CONDUCTION IN SEMICONDUCTORS Electrons and holes in an intrinsic semiconductors,
Diodes mplest nonlinear circuit element Basic operation sets the foundation for Bipolar Junction Transistors (BJTs) Also present in Field Effect Transistors (FETs) Ideal diode characteristic anode cathode
Charge carriers and conduction: Chapter 12: Electrical Properties Charge carriers include all species capable of transporting electrical charge, including electrons, ions, and electron holes. The latter
THE STUDY OF ANTIFERROMAGNETISM IN DILUTED MAGNETIC SEMICONDUCTOR CDMNTE By Gebru Tadesse A THESIS PRESENTED TO THE SCHOOL OF GRADUATE STUDIES ADDIS ABABA UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
Material Science II. d Electron systems 1. Electronic structure of transition-metal ions (May 23) 2. Crystal structure and band structure (June 13) 3. Mott s (June 20) 4. Metal- transition (June 27) 5.
Calculating Band Structure Nearly free electron Assume plane wave solution for electrons Weak potential V(x) Brillouin zone edge Tight binding method Electrons in local atomic states (bound states) Interatomic
Semiconductor Physics Problems 2015 Page and figure numbers refer to Semiconductor Devices Physics and Technology, 3rd edition, by SM Sze and M-K Lee 1. The purest semiconductor crystals it is possible
Semi-Conductors In the metal materials considered earlier, the coupling of the atoms together to form the material decouples an electron from each atom setting it free to roam around inside the material.
A SEMICONDUCTOR DIODE P-N Junction Analog Electronics Pujianto Department of Physics Edu. State University of Yogyakarta A Semiconductor Devices A Semiconductor devices can be defined as a unit which consists,
KL 4. - characteristics of electric conductors 4.1 ntroduction f an electric conductor is connected to a voltage source with voltage a current is produced. We define resistance being the ratio of the voltage
UConn ECE 411, Semiconductor Devices and Nanostructures Lecture Week 1 January 17, 017 Device Operation: One of the objectives of this course is to understand operation of carrier transport in semiconductor
SOLID STATE PHYSICS Second Edition J. R. Hook H. E. Hall Department of Physics, University of Manchester John Wiley & Sons CHICHESTER NEW YORK BRISBANE TORONTO SINGAPORE Contents Flow diagram Inside front
Chapter 1 INTRODUCTION TO SEMICONDUCTORS MATERIAL Objectives Discuss basic structures of atoms Discuss properties of insulators, conductors, and semiconductors Discuss covalent bonding Describe the conductions
Qualitative Picture of the Ideal Diode G.R. Tynan UC San Diego MAE 119 Lecture Notes Band Theory of Solids: From Single Attoms to Solid Crystals Isolated Li atom (conducting metal) Has well-defined, isolated
Semiconductor Detectors Summary of Last Lecture Band structure in Solids: Conduction band Conduction band thermal conductivity: E g > 5 ev Valence band Insulator Charge carrier in conductor: e - Charge
The Birnie Group solar class and website were created with much-appreciated support from the NSF CRCD Program under grants 0203504 and 0509886. Continuing Support from the McLaren Endowment is also greatly
ADVANCED UNDERGRADUATE LABORATORY HALL Semiconductor Resistance, Band Gap, and Hall Effect Revisions: September 2016, January 2018: Young-June Kim November 2011, January 2016: David Bailey October 2010:
B. Halperin Spin lecture 1 Spins and spin-orbit coupling in semiconductors, metals, and nanostructures Behavior of non-equilibrium spin populations. Spin relaxation and spin transport. How does one produce
A Seminar report On Spintronics Submitted in partial fulfillment of the requirement for the award of degree of Electronics SUBMITTED TO: SUBMITTED BY: www.studymafia.org www.studymafia.org Preface I have
Electrical material properties U = I R Ohm s law R = ρ (l/a) ρ resistivity l length σ = 1/ρ σ conductivity A area σ = n q μ n conc. of charge carriers q their charge μ their mobility μ depends on T, defects,
Semiconductor Physics fall 2012 problems 1. An n-type sample of silicon has a uniform density N D = 10 16 atoms cm -3 of arsenic, and a p-type silicon sample has N A = 10 15 atoms cm -3 of boron. For each
UNIVERSITY OF CALIFORNIA College of Engineering Department of Electrical Engineering and Computer Sciences EE143 Professor Ali Javey Spring 2009 Exam 1 Name: SID: Closed book. One sheet of notes is allowed.
A3-1 HALL EFFECT Last Revision: August, 21 2007 QUESTION TO BE INVESTIGATED How to individual charge carriers behave in an external magnetic field that is perpendicular to their motion? INTRODUCTION The
5 TEST 2 Formulae and data E = hc " " = neµ = ne2 # m N A = 6.023x10 23 ( mol "1 ) F = q( vxb) g = " A L I = nave For hydrogen : E 0 4 e m = 2 2 32# " h 0 2 4 e m = 2 2 8# " h 0 2 = 13.60ev; a 0 = 0.53x10!
Introduction into defect studies in ceramic materials(iii) Structure, Defects and Defect Chemistry Z. Wang January 18, 2002 1. Mass, Charge and Site Balance The Schottky reactions for NaCl and MgO, respectively,
Chapter 1 Conduction in Semiconductors 1.1 Conduction by electrons and holes: the valence bond model It is almost a commonplace that the outer (valence) electrons in a metal are free to move through the
Modern Physics (PHY 3305) Lecture Notes Modern Physics (PHY 3305) Lecture Notes Solid-State Physics: Superconductivity (Ch. 10.9) SteveSekula, 1 April 2010 (created 1 April 2010) Review no tags We applied
Surfaces, Interfaces, and Layered Devices Building blocks for nanodevices! W. Pauli: God made solids, but surfaces were the work of Devil. Surfaces and Interfaces 1 Interface between a crystal and vacuum
PowerPoint to accompany Chapter 6 Periodic Properties of the Elements Development of the Periodic Table Elements in the same group generally have similar chemical properties. Properties are not identical,
HALL EFFECT In a Ga!ium Arsenide Semiconductor Jason Robin Fall 07 Phy Adv Lab Ha! Effect 1 HALL EFFECT In a Ga!ium Arsenide Semiconductor Jason Robin University of Rochester Fall 07 PHY ADV LAB Introduction
Understanding Solid State Physics Additional Questions Sharon Ann Holgate Questions for Chapter 2 2.1(a) What structure does the compound caesium iodide crystallise in? 2.1(b) What does the term "coordination
Modern Physics for Scientists and Engineers International Edition, 4th Edition http://optics.hanyang.ac.kr/~shsong 1. THE BIRTH OF MODERN PHYSICS 2. SPECIAL THEORY OF RELATIVITY 3. THE EXPERIMENTAL BASIS
CHAPTER 2 Atomic Structure And Bonding 2-1 Structure of Atoms ATOM Basic Unit of an Element Diameter : 10 10 m. Neutrally Charged Nucleus Diameter : 10 14 m Accounts for almost all mass Positive Charge
Lectures on MEMS and MICROSYSTEMS DESIGN and MANUFACTURE Chapter 3 Engineering Science for Microsystems Design and Fabrication In this Chapter, we will present overviews of the principles of physical and
Chapter 3 Properties of Nanostructures In Chapter 2, the reduction of the extent of a solid in one or more dimensions was shown to lead to a dramatic alteration of the overall behavior of the solids. Generally,
Surfaces, Interfaces, and Layered Devices Building blocks for nanodevices! W. Pauli: God made solids, but surfaces were the work of Devil. Surfaces and Interfaces 1 Role of surface effects in mesoscopic
IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 1, NO. 1, MARCH 2002 19 Semiconductor Spintronics Hiro Akinaga and Hideo Ohno, Member, IEEE Abstract We review recent progress made in the field of semiconductor
UNIVERSITY OF CALIFORNIA College of Engineering Department of Electrical Engineering and Computer Sciences EECS 143 Fall 2008 Exam 1 Professor Ali Javey Answer Key Name: SID: 1337 Closed book. One sheet
15 2. Basic Electrical Parameters of Semiconductors: Sheet Resistivity, Resistivity and Conduction Type 2.1 Objectives 1. Familiarizing with experimental techniques used for the measurements of electrical
Sensor devices Magnetic sensors Outline 5 Magnetic Sensors Introduction Theory GalvanomagneticG Effects Applications Introduction A magnetic sensor is a transducer that converts a magnetic field into an
1. Motion of the charges occurs in two semicircular containers, D 1 and D 2 referred to as the Dees 2. The Dees are evacuated in order to minimize energy loss from collisions 3. A high frrequency alternating
http://en.wikipedia.org/wiki/bravais_lattice Introduction to Solid State Crystalline vs. non-crystalline solids: Lattice Unit cell No. of spheres in a unit cell : Bravais lattices In geometry and crystallography,
Graphene and Carbon Nanotubes 1 atom thick films of graphite atomic chicken wire Novoselov et al - Science 306, 666 (004) 100μm Geim s group at Manchester Novoselov et al - Nature 438, 197 (005) Kim-Stormer
0. Introduction: Semiconductor device structures are traditionally divided into homojunction devices (devices consisting of only one type of semiconductor material) and heterojunction devices (consisting
Chapter 7 Periodic Properties of the Elements DEVELOPMENT OF THE PERIODIC TABLE Elements in the same group generally have similar chemical properties. Properties are not identical, however. Brown, LeMay,