2 Why Semiconductors? Information processing (Amps, A/D, processors, tranceivers…)Information acquisition(sensors)Image, sound, temperature, pressure, …Image, sound, temperature, pressure, …Information transmission(wires, busses, cables, optical fibers, or just air!)Brains and muscles of the system are made of semiconductorsMetals & dielectrics are used as transmission mediaWhy?Information processing(tranceivers, processors, …)Displays
3 What’s common for all the core components? Light, sound, temperature, pressure, …Voltage, currentVoutVinsensorVinVinAVoutVoutoutputinputVinModulation of some physical quantity (output) by some othersSome kind of gain, conversion ratio, sensitivity, etc
4 Example: Field-Effect Transistors (FETs) Semiconductor vs Metal For SiO2 dielectric, breakdown field Eb ~ 107 V/cm. No matter how thick it is, the maximum induced carrier area density is r0Eb/q = 2 × 1013 /cm2.VinVoutVoutVinFor a 1 m thick Si channel,ni = 1.45 × 1010 /cm3,the background carrier area density isni × 104 cm = 1.45 × 106 /cm2.In principle, the area carrier density, and therefore the channel conductance, can be modulated by 7 orders of mag!!!FET’s are building blocks.GSDSchematic illustration of a FETFor Al, n = 1.8 × 1023 /cm3. Even for 1 nm thin (monolayers!) Al, the background carrier area density is 1.8 × 1016 /cm2. The conductance can only be modulated by 0.1%!!!What are semiconductors, anyway???
5 A Digression: The Vast Field of Electrical Engineering Solid-state physicsDevice physicscircuitsTransistor levelHigher levelInformation theoryControl theorychemistrySemiconductor physicsMaterials scienceSemiconductor processingEconomicsCore knowledge body of the device engineerDifferent disciplines are different levels of extractionDevice engineers are at the junction of many disciplinesFollow your passion
6 A Digression: The Vast Field of Electrical Engineering Solid-state physicsDevice physicscircuitsTransistor levelHigher levelInformation theoryControl theorychemistrySemiconductor physicsMaterials scienceSemiconductor processingEconomicsCore knowledge body of the device engineerBut, each small field can consume one’s entire lifeSo, how can one be a good device engineer???Chuang Tzu: My life is limited while knowledge is unlimited. Pursuing the unlimited with the limited, it is just hopeless!莊子： 吾生也有涯 而知也無涯 以有涯逐無涯 殆矣
7 A Digression: The Vast Field of Electrical Engineering Solid-state physicsDevice physicscircuitsTransistor levelHigher levelInformation theoryControl theorychemistrySemiconductor physicsMaterials scienceSemiconductor processingEconomicsCore knowledge body of the device engineerHow can one be a good device engineer???The big picture!This course is about the big picture.It willed be tailored to suit your research interest; we have a small class after all.
8 Let’s get to know each other! Name, yearPrevious exposure to quantum mechanics, solid-state physics, device physics, processing, ckt design (courses + hands-on)AdvisorResearch field, particular topicLike it?Class meeting schedule?
9 Syllabus Course Objective: To provide students with an understanding of device physics and advanced semiconductor device concepts.TopicsReview of Semiconductor physicsCrystal structure, band structures, band structure modification by alloys, heterostructures, and strainCarrier statisticsScattering, defects, phonons, mobility, transport in heterostructuresDevice conceptsMOSFETs, MESFETs, MODFETs, TFTsHeterojunction bipolar transistors (HBTs)Semiconductor processingPhotodiodes, LEDs, semiconductor lasers(optional) resonant tunneling devices, quantum interference devices, single electron transistors, quantum dot computing, ...Introduction to nanoelectronics
10 Syllabus (Cont’d) Reference books Jasprit Singh, Physics of Semiconductors and Their HeterostructursReads like somebody’s notes. May not be the most elegant or strict from a physics point of view, but definitely serves semiconductor folks well. Intriguing and stimulating.Jasprit Singh, Semiconductor Devices:Basic PrinciplesBook by the same author on Devices but including semiconductor physics & processing.U. K. Mishra & J. Singh, Semiconductor Device Physics and DesignE-book available on line thru UT Lib.Karl Hess, Advanced Theory of Semiconductor DevicesThin, but covers lots of stuff at advanced levelsBen Streetman, Solid State Electronic DevicesFrom basic physics to device concepts. Oldie goodie.S. M. Sze (施敏), Physics of Semiconductor DevicesThe “Bible” of device engineers. Not for beginners. Keep it in mind or on your shelf; an excellent reference book for your future career.R. S. Muller & T. I. Kamins, Device Electronics for Integrated CircuitsAn undergrad textbook on Si microelectronics, but good to have. I go back to it quite often.J. D. Plummer, M. D. Deal, P. B. Griffin, Silicon VLSI technology: fundamentals, practice and modelingBest textbook on processing, by the people who developed many of the models.
11 Syllabus (Cont’d) Journals IEEE Electron Device Letters IEEE Transactions on Electron DevicesApplied Physics LettersJournal of Applied PhysicsWebsitesWikipedia (Are you kidding? No!)Ioffe Physico-Technical InstitutePhysical properties of many semiconductors.
12 Syllabus (Cont’d: The Tough Part) EvaluationClassroom participation, performance (15%)Homework / Mini projects – simple (20%)Term project: Review of a selected specific area, oral presentation on the topic of the paper, oral exam (65%)The topic may or may not be closely related to your research, but cannot be your research topic per se. Need my okay on the topic before it’s too late.The good news: It’s not that tough…The population is too small. Any distribution does not have any statistical meaning. Which means, you could all get A’s. On the other hand, you could …
13 What are semiconductors, anyway??? Back to BusinessWhat are semiconductors, anyway???What answers do you have now?Long way to go to answer this question.
14 Review of Semiconductor Physics Quantum mechanicsShrödinger equationThe equation that scared EinsteinStationary statesSpecial case: free spaceE-k dispersion: light wave vs de Broglie waveThe concept of eigenstatesWave packetsThe uncertainty principle