EE236 Electronics. Computer and Systems Engineering Department. Faculty of Engineering Alexandria University. Fall 2014

Transcription

1 EE236 Electronics Computer and Systems Engineering Department Faculty of Engineering Alexandria University Fall 2014 Lecturer: Bassem Mokhtar, Ph.D. Assistant Professor Department of Electrical Engineering Alexandria University Introduction 1-1

2 Outline Course Overview Quick Review on Circuit Basics Introduction to Electronics Semiconductor Physics Introduction 1-2

3 Course details Lecture hours: 4 Two Lectures weekly (Sundays and Wednesdays) Tutorial hours: 1 One tutorial class every two weeks Lab hours: 1 One experiment every two weeks Course website: ectronics_csed/electronics_csed.htm Introduction 1-3

4 Course outline Introduction to semiconductor physics and materials (1.5 weeks) Conductors vs. Insulators vs. Semiconductors p-type, n-type p-n junctions (1.5 weeks) Diodes and diode circuits BJT transistors (2 weeks) Different types of BJT circuits DC and AC Biasing FET transistors (one week) Brief Introduction Mid-Term Exams (week: 22/11 to 27/11) MOSFET (2 weeks) Different types of MOSFET circuits DC and AC biasing CMOS (2 weeks) Operational Amplifiers (one week) Logic and Integrated Circuits (one week) Memory Introduction 1-4

5 Course Objectives Having successfully completed this course, the student will be able to: (a) Comprehensively understand of electronic circuits and devices (diodes, BJTs, MOSFETs) (b) Learn physical models of the operation of semiconductor devices (c) Examine the design and operation of important circuits that utilize these devices Course Prerequisites: Course: EE x11 Electric Circuits Do you remember? Your last second semester Introduction 1-5

6 References Lecture Notes Microelectronic Circuits, Sedra Smith,5 th edition, Electronic Devices and Circuit Theory, Boylestad and Nashelsky, 7 th edition Fundamentals of Microelectronics, Razavi, 2006 Introduction 1-6

7 Assessment Class and Lab Work: 10% Assignments Simulations (LTspice IV) and reports Midterm exam: 20% (week 22/11 to 27/11) Project: 10% (team up to 3 students) Submitting project paper related to an electronic device (Due date: January first, 2015 and Project presentation and discussion will be through the week of January 3 to January 8) Grading will relay on project material understanding, quality of submitted paper, presentation and oral discussion +2% bonus for project device/topic simulations Final exam: 60% Introduction 1-7

8 Project The final project will run in parallel with the course. Each team (up to three students per team) will choose freely an electronic device/topic (not covered in the course) The electronic device/topic will be chosen by the team on a first-come firstserve (FCFS) basis (no more than one team per device) The team will need to do more extensive searching for the latest research work concerning the selected device/topic Each team will prepare and submit a project paper (using WORD, LATEX) which provides qualitative study for the their device /topic via including: Schematic of related device structure illustrating the key operating principles Representative electrical data showing how related device works (e.g., current-voltage curves) Discussion of the basic operation of related device and key variations thereof Discussion of the major challenges to realizing the related device in a technology Table of performance measure metrics for the related device Table of comparison which compare the related device with other relevant/similar devices Citation of all referenced work, figures, etc (You can add other issues based on your selected device/topic) example: experimental study and results Each team must work on a different device/topic Teams will present their project and they will be discussed Introduction 1-8

9 Examples of Project Topics Carbon nanotube field effect transistor Ballistic transistors Resonant Tunneling Diode Coulomb blockade and single electron transistor Graphene field effect transistor Dissipation in FETs Nano Sensors Flexible Electronics Quantum effects in nanoscale electronic devices Raspberry Pi FPGA DEADLINE for Project Team Formation and Project Topic Selection: 25 th October. Introduction 1-9

10 Attendance Attendance in class is considered essential Office Hours Wednesdays (11:00 am to 12:00 pm) or appointment me at Course TA Eng. Nour Nabil (tutorials and labs) Introduction 1-10

11 Quick Review (Circuit Basics) Introduction 1-11

12 Quick Review (Circuit Basics) Introduction 1-12

13 Quick Review (Circuit Basics) Test your self now: Write down equation for calculating i B in terms of voltages, currents and resistors Introduction 1-13

14 Quick Review (Circuit Basics) Introduction 1-14

15 Quick Review (Circuit Basics) Introduction 1-15

16 Quick Review (Circuit Basics) Introduction 1-16

17 Quick Review (Circuit Basics) Introduction 1-17

18 Quick Review (Circuit Basics) Introduction 1-18

19 Quick Review (Circuit Basics) Introduction 1-19

20 Introduction to Electronics Block diagram of a simple electronic system: an AM radio. Introduction 1-20

21 Introduction to Electronics Common Blocks in an Electronic System Amplifiers Filters Signal sources (oscillators) Wave-shaping circuits Digital logic functions Memories Power supplies Converters Introduction 1-21

22 Introduction to Electronics Analog vs. Digital Signals Introduction 1-22

23 Introduction to Electronics Analog to Digital Conversion Introduction 1-23

24 Introduction to Electronics Signals and Noise Introduction 1-24

25 Introduction to Electronics Analog vs. Digital Digital circuits advantages Better immunity to noise Easier to implement with IC techniques More adaptable to variable uses Analog Circuits advantages Require less devices Better to deal with low signal amplitudes Better to deal with high frequencies Introduction 1-25

26 What is the foundation material for all modern electronics? Answer: Semiconductor materials Introduction 1-26

27 Introduction 1-27

28 Brief History Rectification in metal-semiconductor contact (Braun, 1874) Theory of thermionic emission (Bethe 1942) Transistor (point-contact transistor) using polycrystalline germanium (Shockley, Bardeen and Brattain, 1947) Bipolar junction transistor (Shockley, 1947) Integrated circuit (Kilby and Noyce, 1958) using bipolar junction transistors Practical metal-oxide-semiconductor (MOS) devices (1960s) Small Scale Integration (SSI) (~10 Trs.chip) ->MSI(~100 Trs/chip)-> LSI (10,000 Trs/chip) in the 1970s) VLSI (~10^5 Trs/chip) -> ULSI (10^6 Trs/chip) in the 1990s Multicore chip processors -> 10^8 Trs/core up to 8 processors by 2010 The International Technology Roadmap for Semiconductors (ITRS) predicts 8 nm feature size with 1000 cores in 2020 Introduction 1-28

29 GOING TO THE FIRST TOPIC Semiconductor Physics Introduction 1-29

30 Introduction 1-30

31 Comparison Conductor Easily can conduct electrical current Least valence electron on the atom-loosely bounded Insulator Does not conduct electrical current under normal condition Most are compounds Lots of electron exist on the valence shell-tightly bounded Semiconductor Element that is neither a conductor nor an insulator but lies between the two element A material that is between conductors and insulators in its ability to conduct electrical current Easily affected by temperature and light energy Most of them have 4 valence electrons on the valence shells-bounded in intermediate strength Introduction 1-31

32 Semiconductor Materials Atom Bohr Model Atom have planetary type of structure consisting central nucleus equipped with the proton and surrounded by orbiting electron Proton are positively charged and electron are negatively charged Atomic number The atomic number is equal to the number of protons in an atom s nucleus Distinguishes the chemical group characteristics Electron shells and orbit Electron near the nucleus have less energy than the outer one Each electron orbits are grouped in shells (energy bands) Maximum number of electrons (Ne) that exist in each shells of atom can be calculated as Ne = 2n 2 where n(1,2,3, ) is the number of the shells. Introduction 1-32

33 Semiconductor Materials Energy level increase as the distance from the nucleus increase Valence electron The outmost electrons are in the valence shells and known as valence electrons Valence shells represents the energy band of an atom The farther the electrons from the nucleus, the higher energy it gets Strongly related defining chemical reaction, bonding structure and electrical properties Semiconductors have four valence electrons at the outermost atomic shell Most conductors have just one electron in the valence shell (high probability to form covalent bonds) Insulators have eight valence electrons Introduction 1-33

34 Semiconductor Materials Valence shells represents the band of energy of an atom Conduction bands Existence of electron valence. Where the electron valence become a free electron when acquire enough additional external energy Energy gaps Energy differences between conduction bands and valence bands (define the required energy for electron valence to be a free electron) Introduction 1-34

35 Lecture Summary Covered material Course Introduction Load, assessment and topics Quick Review (circuit basics) Introduction to Electronics and Semiconductor Physics Material to be covered next lecture Continue Semiconductor Physics Types of semiconductors Types of charge carriers in semiconductors Creation of electron-hole pairs Doping Introduction 1-35