ELEC 3908, Physical Electronics, Lecture 19. BJT Base Resistance and Small Signal Modelling


 Bartholomew Butler
 2 years ago
 Views:
Transcription
1 ELEC 3908, Physical Electronics, Lecture 19 BJT Base Resistance and Small Signal Modelling
2 Lecture Outline Lecture 17 derived static (dc) injection model to predict dc currents from terminal voltages This lecture begins by considering the resistance associated with current flow through the base region base resistance Now consider small signal operation and derive equivalent circuits for low and high frequency operation Will also use the high frequency equivalent circuit to define the transit frequency, a common figure of merit for bipolar transistors Page 192
3 Physical Origin of Base Resistance So far BJT analysis has been 1D, i.e. no lateral effects considered More accurate modelling of structure requires consideration of base current flow: From contact, I B must flow through base material to edge of active region Base current flow to emitter occurs in a distributed way along path into active device Page 193
4 Extrinsic Base Resistance The extrinsic (or external) base region is that between the active area and the base contact region, assume width is s B Resistance of this region can be determined from basic equation for resistance from resistivity  if ρ Bx is the resistivity of the extrinsic base region then ρl ρbxsb rbx = = A lw E B Page 194
5 Intrinsic Base Resistance  Geometry The intrinsic (or internal) base region is the volume of the active device area enclosed by the neutral base width and the emitter width and length Modelling of this resistance is more complicated because the current flow is not 1 dimensional  base current enters the side and leaves the top (to be injected into the emitter in forward active operation) Page 195
6 Intrinsic Base Resistance  Modelling Assume linear distribution of i B The lhs voltage due to the distributed voltage drop through the region is b 1 E Veff = Rxixdx b ( ) ( ) E The resistance from the lhs edge to a point x is Bix Rx ( )= ρ Wl The linearly distributed current is 0 B E ix ( )= ib 1 x b E Page 196
7 Intrinsic Base Resistance  Modelling Substituting the expressions for R(x) and i(x) into the V eff expression gives V eff = 1 b E b E 0 ρbix Wl B E i B 1 x b E dx Performing the integral and substituting limits gives the result r bb Veff Bib = = 1 ρ i 6 Wl B The effective intrinsic base resistance is therefore 1/6 of the value obtained if i B was flowing through the region E B E Page 197
8 Example 19.1: Base Resistance Calculation Calculate the intrinsic and extrinsic base resistances for the structure and potentials shown below. Assume the internal and external base dopings are identical, and that the base separation s B is 1.5 μm. The emitter width is 1.0 μm and the length is 10.0 μm. Page 198
9 Example 19.1: Solution Since the intrinsic and extrinsic base regions are identically doped, their resistivities will be the same, given by ρ Bx 1 1 = ρbi = = qpμ p The external base resistance is therefore (note that the neutral base width was calculated in an earlier example) r Bx 4 ρbxsb = = Wl B E 4 4 And the intrinsic base resistance is therefore r Bi 4 1 ρ BibE = = 6 Wl B E 4 4 = 013. Ωcm = 139 Ω = 155. Ω Page 199
10 Low Frequency Small Signal Parameters The transconductance g m, the rate of change of collector current with base emitter voltage, is given by g m di dv C BE d dv BE qa D n WB E nb Bo To account for the back injection component of base current in forward active operation, another conductance g π, the rate of change of base current with baseemitter voltage, is used, where e qv BE kt = q kt I C g π di dv B BE d dv BE qa D W p E pe Eo E e qv BE kt q kt I q kt I IB = B = C = 123 { IC g m 1 β F g β m F Page 1910
11 Low Frequency Small Signal Equivalent Circuit Now assemble the base resistance and conductance parameters into an equivalent circuit valid for small signal operation Include a controlled current source to model the dependence of collector current variation on base current variation, and an output resistance to model the Early effect Result is a low frequency hybridπ small signal equivalent circuit Page 1911
12 Example 19.2: Conductance Parameter Calculations Calculate the parameters r π and g m for the device of example Page 1912
13 Example 19.2: Solution Using the value of I C calculated from the injection model equation g m = = mhos From the value of g m found above and the forward active current gain already calculated in an earlier example g π g m = = β F = mhos = 233. kω Page 1913
14 Depletion Capacitance in the BJT Structure Each pnjunction in the bipolar structure has an associated depletion capacitance C depbc is the absolute depletion capacitance (F) of the base collector junction, C depbe is the absolute capacitance (F) of the baseemitter junction Recall from diode discussion (lecture 13) ˆ ˆ ε C ( 0) Si dep Cdep ( VD ) = = W V 1 V V ( ) D D bi Page 1914
15 BJT Depletion Capacitance Models Write models for each junction of the form of the original pnjunction model equation C$ ( V ) depbe BE = C$ ( 0) depbe ( 1 V V ) BE bibe z BE C$ ( 0) depbe = ε W BE Si ( 0) C$ ( V ) depbc BC = C$ ( 0) depbc ( 1 V V ) BC bibc z BC C$ ( 0) depbc = ε W BC Si ( 0) The total (absolute) capacitances are then the per unit area terms multiplied by the emitter area C = C$ A C = C$ A depbc depbc E depbe depbe E Page 1915
16 Physical Origin of Base Diffusion Capacitance Recall that in general, capacitance is associated with the requirement to source or sink charge when changing a terminal s potential Because the stored charge in the base must be changed if V BE is changed, a capacitance will be created between the base and emitter terminals This is termed the base diffusion capacitance Page 1916
17 Base Diffusion Capacitance Model The base diffusion capacitance C π (in F, not a per unit area term) can be modeled in terms of the base transit time τ B, the time taken to cross the neutral base region C The transit time is given in terms of physical parameters for a constant doped base by = g π τ B m τ B = W 2D 2 B nb Page 1917
18 High Frequency Small Signal Equivalent Circuit If the capacitances are added to the low frequency equivalent circuit, the high frequency hybridπ equivalent circuit is obtained Note that the baseemitter capacitances appear inside the base resistances, since they are part of the basic internal transistor structure Page 1918
19 Example 19.3: Capacitance Calculations Calculate the high frequency hybridπ equivalent circuit capacitances for the device in example Page 1919
20 Example 19.3: Solution The first step in determining the depletion capacitances is to find the zero bias depletion widths. Applying the formula for W at zero bias to each junction (using previously calculated built in potentials) gives W BE 2ε Si 1 1 ( 0) = + VbiBE = q N N AB DE 5 cm W BC 2ε Si 1 1 ( 0) = + VbiBC = q N N The zero bias capacitances are therefore AB DC 5 cm C$ ( 0) depbe ε Si. $ ε Si = = Fcm CdepBC( 0) = = W ( 0) W ( 0) BE BC Fcm Page 1920
21 Example 19.3: Solution (con t) The capacitances at bias are therefore (note that the grading coefficient is 1/2 for uniformly doped junctions) C$ ( 08. ) = depbe C$ ( 07. ) = depbc ( ) ( ) = = The absolute depletion capacitances are therefore C C depbe depbc ( ) ( ) 7 8 Fcm 2 Fcm = = = = F F Page 1921
22 Example 19.3: Solution (con t) The base transit time is found from τ B W 2D ( ) B 10 = = = nb sec The base diffusion capacitance is therefore found using the transit time and the previously calculated transconductance as C = g = = F π τ B m Page 1922
23 Transit Frequency Measurement Configuration One widely used figure of merit in bipolar performance is the transit frequency f T, the frequency at which the current gain with the collector and emitter short circuited becomes unity Page 1923
24 Transit Frequency Analysis To determine f T, the high frequency small signal hybridp circuit can be used The effect of the collectoremitter short circuit is to short the output conductance r o The phasor collector current will be given by (note point a is ground) ( ω ) I = g V jωc V = V g j C C m b e depbc b e b e m depbc Page 1924
25 Transit Frequency Analysis (con t) The base current phasor will be given by I ( g jωc jωc ) = V + + B b e π π depbc The ratio of collector current phasor to base current phasor is therefore I I C B = gm jωcdepbc 1 g + jω C + C + C jω C C g τ π ( + + ) ( ) ( ) π depbe depbc depbe depbc m B Page 1925
26 Transit Frequency Analysis (con t) The transit frequency is then defined by I I C 1 1 = 2πf C C g T (( + ) + τ ) B f = f T depbe depbc m B And hence f T is given in terms of physical parameters as f T = 2π 1 (( C C ) g ) depbc + depbe m + τb Faster transit time, reduced capacitance and increased transconductance all improve the transit frequency Page 1926
27 Example 19.4: Transit Frequency Calculation Calculate the transit frequency for the device of example Page 1927
28 Example 19.4: Solution The required values have all been calculated previously, so the result is obtained by substituting the values f T = 1 ( ) ( ) 2π = Hz This example transistor therefore has a transit frequency of 0.56 GHz. A modern commercial bipolar process would offer devices with an f T of GHz. Page 1928
29 Lecture Summary Current flow in bipolar structure experiences external and internal base resistance mechanisms are very different Low frequency small signal equivalent circuit contains r bb and r bx (internal/external base resistances), g π (dependence of back injection current on V BE), g m ( transconductance) and r o the output resistance (Early effect) High frequency small signal equivalent circuit contains the same elements plus C depbc, C depbe (depletion capacitances) and C π (diffusion capacitance) The transit frequency f T incorporates many of the important high frequency parameters, and so is a useful figure of merit of high frequency performance Page 1929
ELEC 3908, Physical Electronics, Lecture 13. Diode Small Signal Modeling
ELEC 3908, Physical Electronics, Lecture 13 iode Small Signal Modeling Lecture Outline Last few lectures have dealt exclusively with modeling and important effects in static (dc) operation ifferent modeling
More informationELEC 3908, Physical Electronics, Lecture 18. The Early Effect, Breakdown and SelfHeating
ELEC 3908, Physical Electronics, Lecture 18 The Early Effect, Breakdown and SelfHeating Lecture Outline Previous 2 lectures analyzed fundamental static (dc) carrier transport in the bipolar transistor
More informationELEC 3908, Physical Electronics, Lecture 17. Bipolar Transistor Injection Models
LC 3908, Physical lectronics, Lecture 17 Bipolar Transistor njection Models Lecture Outline Last lecture looked at qualitative operation of the BJT, now want to develop a quantitative model to predict
More informationDigital Integrated CircuitDesign
Digital Integrated CircuitDesign Lecture 5a Bipolar Transistor Dep. Region Neutral Base n(0) b B C n b0 P C0 P e0 P C xn 0 xp 0 x n(w) b W B Adib Abrishamifar EE Department IUST Contents Bipolar Transistor
More informationDevice Physics: The Bipolar Transistor
Monolithic Amplifier Circuits: Device Physics: The Bipolar Transistor Chapter 4 Jón Tómas Guðmundsson tumi@hi.is 2. Week Fall 2010 1 Introduction In analog design the transistors are not simply switches
More informationStudent Number: CARLETON UNIVERSITY SELECTED FINAL EXAMINATION QUESTIONS
Name: CARLETON UNIVERSITY SELECTE FINAL EXAMINATION QUESTIONS URATION: 6 HOURS epartment Name & Course Number: ELEC 3908 Course Instructors: S. P. McGarry Authorized Memoranda: Nonprogrammable calculators
More informationFinal Examination EE 130 December 16, 1997 Time allotted: 180 minutes
Final Examination EE 130 December 16, 1997 Time allotted: 180 minutes Problem 1: Semiconductor Fundamentals [30 points] A uniformly doped silicon sample of length 100µm and crosssectional area 100µm 2
More informationLecture 17  The Bipolar Junction Transistor (I) Forward Active Regime. April 10, 2003
6.012  Microelectronic Devices and Circuits  Spring 2003 Lecture 171 Lecture 17  The Bipolar Junction Transistor (I) Contents: Forward Active Regime April 10, 2003 1. BJT: structure and basic operation
More informationBipolar junction transistor operation and modeling
6.01  Electronic Devices and Circuits Lecture 8  Bipolar Junction Transistor Basics  Outline Announcements Handout  Lecture Outline and Summary; Old eam 1's on Stellar First Hour Eam  Oct. 8, 7:309:30
More informationfigure shows a pnp transistor biased to operate in the active mode
Lecture 10b EE215 Electronic Devices and Circuits Asst Prof Muhammad Anis Chaudhary BJT: Device Structure and Physical Operation The pnp Transistor figure shows a pnp transistor biased to operate in the
More informationRecitation 17: BJTBasic Operation in FAR
Recitation 17: BJTBasic Operation in FAR BJT stands for Bipolar Junction Transistor 1. Can be thought of as two pn junctions back to back, you can have pnp or npn. In analogy to MOSFET small current
More informationUNIVERSITY OF CALIFORNIA, BERKELEY College of Engineering Department of Electrical Engineering and Computer Sciences
UNIVERSITY OF CALIFORNIA, BERKELEY College of Engineering Department of Electrical Engineering and Computer Sciences EE 105: Microelectronic Devices and Circuits Spring 2008 MIDTERM EXAMINATION #1 Time
More informationBJT  Mode of Operations
JT  Mode of Operations JTs can be modeled by two backtoback diodes. N+ P N N+ JTs are operated in four modes. HO #6: LN 251  JT M Models Page 1 1) Forward active / normal junction forward biased junction
More informationELEC 3908, Physical Electronics, Lecture 26. MOSFET Small Signal Modelling
ELEC 3908, Physical Electronics, Lecture 26 MOSFET Small Signal Modelling Lecture Outline MOSFET small signal behavior will be considered in the same way as for the diode and BJT Capacitances will be considered
More informationI. Frequency Response of Voltage Amplifiers
I. Frequency Response of Voltage Amplifiers A. CommonEmitter Amplifier: V i SUP i OUT R S V BIAS R L v OUT V Operating Point analysis: 0, R s 0, r o >, r oc >, R L > Find V BIAS such that I C
More informationECE342 Test 2 Solutions, Nov 4, :008:00pm, Closed Book (one page of notes allowed)
ECE342 Test 2 Solutions, Nov 4, 2008 6:008:00pm, Closed Book (one page of notes allowed) Please use the following physical constants in your calculations: Boltzmann s Constant: Electron Charge: Free
More informationForwardActive Terminal Currents
ForwardActive Terminal Currents Collector current: (electron diffusion current density) x (emitter area) diff J n AE qd n n po A E V E V th  e W (why minus sign? is by def.
More informationLecture 38  Bipolar Junction Transistor (cont.) May 9, 2007
6.72J/3.43J  Integrated Microelectronic Devices  Spring 27 Lecture 381 Lecture 38  Bipolar Junction Transistor (cont.) May 9, 27 Contents: 1. Nonideal effects in BJT in FAR Reading material: del Alamo,
More informationInstitute of Solid State Physics. Technische Universität Graz. Exam. Feb 2, 10:0011:00 P2
Technische Universität Graz nstitute of Solid State Physics Exam Feb 2, 10:0011:00 P2 Exam Four questions, two from the online list. Calculator is ok. No notes. Explain some concept: (tunnel contact,
More informationEE105 Fall 2015 Microelectronic Devices and Circuits: Semiconductor Fabrication and PN Junctions
EE105 Fall 2015 Microelectronic Devices and Circuits: Semiconductor Fabrication and PN Junctions Prof. Ming C. Wu wu@eecs.berkeley.edu 511 Sutardja Dai Hall (SDH) 1 pn Junction ptype semiconductor in
More informationLecture 17. The Bipolar Junction Transistor (II) Regimes of Operation. Outline
Lecture 17 The Bipolar Junction Transistor (II) Regimes of Operation Outline Regimes of operation Largesignal equivalent circuit model Output characteristics Reading Assignment: Howe and Sodini; Chapter
More informationEE105  Fall 2006 Microelectronic Devices and Circuits
EE105  Fall 2006 Microelectronic Devices and Circuits Prof. Jan M. Rabaey (jan@eecs) Lecture 21: Bipolar Junction Transistor Administrative Midterm Th 6:308pm in Sibley Auditorium Covering everything
More informationCLASS 3&4. BJT currents, parameters and circuit configurations
CLASS 3&4 BJT currents, parameters and circuit configurations I E =I Ep +I En I C =I Cp +I Cn I B =I BB +I En I Cn I BB =I Ep I Cp I E = I B + I C I En = current produced by the electrons injected from
More informationLecture 17 The Bipolar Junction Transistor (I) Forward Active Regime
Lecture 17 The Bipolar Junction Transistor (I) Forward Active Regime Outline The Bipolar Junction Transistor (BJT): structure and basic operation I V characteristics in forward active regime Reading Assignment:
More informationChargeStorage Elements: BaseCharging Capacitance C b
ChargeStorage Elements: BaseCharging Capacitance C b * Minority electrons are stored in the base  this charge q NB is a function of the baseemitter voltage * base is still neutral... majority carriers
More informationLecture 23: Negative Resistance Osc, Differential Osc, and VCOs
EECS 142 Lecture 23: Negative Resistance Osc, Differential Osc, and VCOs Prof. Ali M. Niknejad University of California, Berkeley Copyright c 2005 by Ali M. Niknejad A. M. Niknejad University of California,
More informationSemiconductor Physics Problems 2015
Semiconductor Physics Problems 2015 Page and figure numbers refer to Semiconductor Devices Physics and Technology, 3rd edition, by SM Sze and MK Lee 1. The purest semiconductor crystals it is possible
More informationLecture 20  pn Junction (cont.) October 21, Nonideal and secondorder effects
6.70J/3.43J  Integrated Microelectronic Devices  Fall 00 Lecture 01 Lecture 0  pn Junction (cont.) October 1, 00 Contents: 1. Nonideal and secondorder effects Reading assignment: del Alamo, Ch.
More informationFor the following statements, mark ( ) for true statement and (X) for wrong statement and correct it.
Benha University Faculty of Engineering Shoubra Electrical Engineering Department First Year communications. Answer all the following questions Illustrate your answers with sketches when necessary. The
More informationElectronic Circuits 1. Transistor Devices. Contents BJT and FET Characteristics Operations. Prof. C.K. Tse: Transistor devices
Electronic Circuits 1 Transistor Devices Contents BJT and FET Characteristics Operations 1 What is a transistor? Threeterminal device whose voltagecurrent relationship is controlled by a third voltage
More informationBipolar Junction Transistor (BJT)  Introduction
Bipolar Junction Transistor (BJT)  Introduction It was found in 1948 at the Bell Telephone Laboratories. It is a three terminal device and has three semiconductor regions. It can be used in signal amplification
More informationLecture 27: Introduction to Bipolar Transistors
NCN www.nanohub.org ECE606: Solid State Devices Lecture 27: Introduction to ipolar Transistors Muhammad Ashraful Alam alam@purdue.edu Alam ECE 606 S09 1 ackground E C E C ase! Point contact Germanium transistor
More informationEECS130 Integrated Circuit Devices
EECS130 Integrated Circuit Devices Professor Ali Javey 9/18/2007 P Junctions Lecture 1 Reading: Chapter 5 Announcements For THIS WEEK OLY, Prof. Javey's office hours will be held on Tuesday, Sept 18 3:304:30
More informationELEC 3908, Physical Electronics, Lecture 23. The MOSFET Square Law Model
ELEC 3908, Physical Electronics, Lecture 23 The MOSFET Square Law Model Lecture Outline As with the diode and bipolar, have looked at basic structure of the MOSFET and now turn to derivation of a current
More information6.012 Electronic Devices and Circuits
Page 1 of 1 YOUR NAME Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology 6.12 Electronic Devices and Circuits Exam No. 1 Wednesday, October 7, 29 7:3 to 9:3
More informationMetaloxidesemiconductor field effect transistors (2 lectures)
Metalidesemiconductor field effect transistors ( lectures) MOS physics (brief in book) Currentvoltage characteristics  pinchoff / channel length modulation  weak inversion  velocity saturation 
More informationSpring Semester 2012 Final Exam
Spring Semester 2012 Final Exam Note: Show your work, underline results, and always show units. Official exam time: 2.0 hours; an extension of at least 1.0 hour will be granted to anyone. Materials parameters
More informationChapter 13 SmallSignal Modeling and Linear Amplification
Chapter 13 SmallSignal Modeling and Linear Amplification Microelectronic Circuit Design Richard C. Jaeger Travis N. Blalock 1/4/12 Chap 131 Chapter Goals Understanding of concepts related to: Transistors
More informationRegional Approach Methods for SiGe HBT compact modeling
Regional Approach Methods for SiGe HBT compact modeling M. Schroter 1),2) and H. Tran 2) 1) ECE Dept., University of California San Diego, La Jolla, CA, USA 2) Chair for Electron Devices and Integr. Circuits,
More informationMemories Bipolar Transistors
Technische Universität Graz nstitute of Solid State Physics Memories Bipolar Transistors Technische Universität Graz nstitute of Solid State Physics Exams February 5 March 7 April 18 June 27 Exam Four
More informationSemiconductor Device Physics
1 emiconductor Device Physics Lecture 8 http://zitompul.wordpress.com 2 0 1 3 emiconductor Device Physics 2 M Contacts and chottky Diodes 3 M Contact The metalsemiconductor (M) contact plays a very important
More information6.012 Electronic Devices and Circuits Spring 2005
6.012 Electronic Devices and Circuits Spring 2005 May 16, 2005 Final Exam (200 points) OPEN BOOK Problem NAME RECITATION TIME 1 2 3 4 5 Total General guidelines (please read carefully before starting):
More informationLecture 15: MOS Transistor models: Body effects, SPICE models. Context. In the last lecture, we discussed the modes of operation of a MOS FET:
Lecture 15: MOS Transistor models: Body effects, SPICE models Context In the last lecture, we discussed the modes of operation of a MOS FET: oltage controlled resistor model I curve (SquareLaw Model)
More informationCHAPTER 4: PN P N JUNCTION Part 2. M.N.A. Halif & S.N. Sabki
CHAPTER 4: PN P N JUNCTION Part 2 Part 2 Charge Storage & Transient Behavior Junction Breakdown Heterojunction CHARGE STORAGE & TRANSIENT BEHAVIOR Once injected across the junction, the minority carriers
More informationIntroduction to Power Semiconductor Devices
ECE442 Power Semiconductor Devices and Integrated Circuits Introduction to Power Semiconductor Devices Zheng Yang (ERF 3017, email: yangzhen@uic.edu) Power Semiconductor Devices Applications System Ratings
More informationLecture 16  The pn Junction Diode (II) Equivalent Circuit Model. April 8, 2003
6.012  Microelectronic Devices and Circuits  Spring 2003 Lecture 161 Lecture 16  The pn Junction Diode (II) Equivalent Circuit Model April 8, 2003 Contents: 1. IV characteristics (cont.) 2. Smallsignal
More informationMicroelectronic Devices and Circuits Lecture 13  Linear Equivalent Circuits  Outline Announcements Exam Two 
6.012 Microelectronic Devices and Circuits Lecture 13 Linear Equivalent Circuits Outline Announcements Exam Two Coming next week, Nov. 5, 7:309:30 p.m. Review Subthreshold operation of MOSFETs Review Large
More informationECE305: Spring 2018 Final Exam Review
C305: Spring 2018 Final xam Review Pierret, Semiconductor Device Fundamentals (SDF) Chapters 10 and 11 (pp. 371385, 389403) Professor Peter Bermel lectrical and Computer ngineering Purdue University,
More information13. Bipolar transistors
Technische Universität Graz Institute of Solid State Physics 13. Bipolar transistors Jan. 16, 2019 Technische Universität Graz Institute of Solid State Physics bipolar transistors npn transistor collector
More informationECE321 Electronics I
ECE321 Electronics I Lecture 4: Physics of Semiconductor iodes Payman ZarkeshHa Office: ECE Bldg. 230B Office hours: Tuesday 2:003:00PM or by appointment Email: pzarkesh.unm.edu Slide: 1 Review of Last
More informationCapacitors Diodes Transistors. PC200 Lectures. Terry Sturtevant. Wilfrid Laurier University. June 4, 2009
Wilfrid Laurier University June 4, 2009 Capacitor an electronic device which consists of two conductive plates separated by an insulator Capacitor an electronic device which consists of two conductive
More informationUniversity of Pittsburgh
University of Pittsburgh Experiment #8 Lab Report The Bipolar Junction Transistor: Characteristics and Models Submission Date: 11/6/2017 Instructors: Dr. Minhee Yun John Erickson Yanhao Du Submitted By:
More informationLecture 35  Bipolar Junction Transistor (cont.) November 27, Currentvoltage characteristics of ideal BJT (cont.)
6.720J/3.43J  Integrated Microelectronic Devices  Fall 2002 Lecture 351 Lecture 35  Bipolar Junction Transistor (cont.) November 27, 2002 Contents: 1. Currentvoltage characteristics of ideal BJT (cont.)
More informationLecture 37: Frequency response. Context
EECS 05 Spring 004, Lecture 37 Lecture 37: Frequency response Prof J. S. Smith EECS 05 Spring 004, Lecture 37 Context We will figure out more of the design parameters for the amplifier we looked at in
More informationLecture 19  pn Junction (cont.) October 18, Ideal pn junction out of equilibrium (cont.) 2. pn junction diode: parasitics, dynamics
6.720J/3.43J  Integrated Microelectronic Devices  Fall 2002 Lecture 191 Lecture 19  pn Junction (cont.) October 18, 2002 Contents: 1. Ideal pn junction out of equilibrium (cont.) 2. pn junction diode:
More informationLecture 29: BJT Design (II)
NCN www.nanohub.org C606: Solid State Devices Lecture 9: JT Design () Muhammad Ashraful Alam alam@purdue.edu Alam C 606 S09 1 Outline 1) Problems of classical transistor ) Poly Si emitter 3) Short base
More information55:041 Electronic Circuits The University of Iowa Fall Exam 2
Exam 2 Name: Score /60 Question 1 One point unless indicated otherwise. 1. An engineer measures the (step response) rise time of an amplifier as t r = 0.35 μs. Estimate the 3 db bandwidth of the amplifier.
More informationECE 497 JS Lecture  12 Device Technologies
ECE 497 JS Lecture  12 Device Technologies Spring 2004 Jose E. SchuttAine Electrical & Computer Engineering University of Illinois jose@emlab.uiuc.edu 1 NMOS Transistor 2 ρ Source channel charge density
More informationL03: pn Junctions, Diodes
8/30/2012 Page 1 of 5 Reference:C:\Users\Bernhard Boser\Documents\Files\Lib\MathCAD\Default\defaults.mcd L03: pn Junctions, Diodes Intrinsic Si Q: What are n, p? Q: Is the Si charged? Q: How could we make
More informationSemiconductor Physics fall 2012 problems
Semiconductor Physics fall 2012 problems 1. An ntype sample of silicon has a uniform density N D = 10 16 atoms cm 3 of arsenic, and a ptype silicon sample has N A = 10 15 atoms cm 3 of boron. For each
More informationElectronic Devices and Circuits Lecture 18  Single Transistor Amplifier Stages  Outline Announcements. Notes on Single Transistor Amplifiers
6.012 Electronic Devices and Circuits Lecture 18 Single Transistor Amplifier Stages Outline Announcements Handouts Lecture Outline and Summary Notes on Single Transistor Amplifiers Exam 2 Wednesday night,
More informationEE 3329 Electronic Devices Syllabus ( Extended Play )
EE 3329  Electronic Devices Syllabus EE 3329 Electronic Devices Syllabus ( Extended Play ) The University of Texas at El Paso The following concepts can be part of the syllabus for the Electronic Devices
More information6.012 Electronic Devices and Circuits
Page 1 of 12 YOUR NAME Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology 6.012 Electronic Devices and Circuits FINAL EXAMINATION Open book. Notes: 1. Unless
More informationAppendix 1: List of symbols
Appendix 1: List of symbols Symbol Description MKS Units a Acceleration m/s 2 a 0 Bohr radius m A Area m 2 A* Richardson constant m/s A C Collector area m 2 A E Emitter area m 2 b Bimolecular recombination
More informationElectronic Devices and Circuits Lecture 14  Linear Equivalent Circuits  Outline Announcements
6.012 Electronic Devices and Circuits Lecture 14 Linear Equivalent Circuits Outline Announcements Handout Lecture Outline and Summary Review Adding refinements to large signal models Charge stores: depletion
More informationn N D n p = n i p N A
Summary of electron and hole concentration in semiconductors Intrinsic semiconductor: E G n kt i = pi = N e 2 0 Donordoped semiconductor: n N D where N D is the concentration of donor impurity Acceptordoped
More informationBiasing the CE Amplifier
Biasing the CE Amplifier Graphical approach: plot I C as a function of the DC baseemitter voltage (note: normally plot vs. base current, so we must return to EbersMoll): I C I S e V BE V th I S e V th
More informationELEC 3908, Physical Electronics, Lecture 27. MOSFET Scaling and Velocity Saturation
ELEC 3908, Physical Electronics, Lecture 27 MOSFET Scaling and Velocity Saturation Lecture Outline Industry push is always to pack more devices on a chip to increase functionality, which requires making
More informationCHAPTER.4: Transistor at low frequencies
CHAPTER.4: Transistor at low frequencies Introduction Amplification in the AC domain BJT transistor modeling The re Transistor Model The Hybrid equivalent Model Introduction There are three models commonly
More informationField effect = Induction of an electronic charge due to an electric field Example: Planar capacitor
JFETs AND MESFETs Introduction Field effect = Induction of an electronic charge due to an electric field Example: Planar capacitor Why would an FET made of a planar capacitor with two metal plates, as
More informationMost matter is electrically neutral; its atoms and molecules have the same number of electrons as protons.
Magnetism Electricity Magnetism Magnetic fields are produced by the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property, their spin. > permanent magnets Magnetic
More informationLecture 11: MOS Transistor
Lecture 11: MOS Transistor Prof. Niknejad Lecture Outline Review: MOS Capacitors Regions MOS Capacitors (3.8 3.9) CV Curve Threshold Voltage MOS Transistors (4.1 4.3): Overview Crosssection and layout
More informationJunction Bipolar Transistor. Characteristics Models Datasheet
Junction Bipolar Transistor Characteristics Models Datasheet Characteristics (1) The BJT is a threeterminal device, terminals are named emitter, base and collector. Small signals, applied to the base,
More informationSession 6: Solid State Physics. Diode
Session 6: Solid State Physics Diode 1 Outline A B C D E F G H I J 2 Definitions / Assumptions Homojunction: the junction is between two regions of the same material Heterojunction: the junction is between
More informationSemiconductor Physics fall 2012 problems
Semiconductor Physics fall 2012 problems 1. An ntype sample of silicon has a uniform density N D = 10 16 atoms cm 3 of arsenic, and a ptype silicon sample has N A = 10 15 atoms cm 3 of boron. For each
More information3 Minority carrier profiles (the hyperbolic functions) Consider a
Microelectronic Devices and Circuits October 9, 013  Homework #3 Due Nov 9, 013 1 Te pn junction Consider an abrupt Si pn + junction tat as 10 15 acceptors cm 3 on te pside and 10 19 donors on te nside.
More informationLecture 15  The pn Junction Diode (I) IV Characteristics. November 1, 2005
6.012  Microelectronic Devices and Circuits  Fall 2005 Lecture 151 Lecture 15  The pn Junction Diode (I) IV Characteristics November 1, 2005 Contents: 1. pn junction under bias 2. IV characteristics
More information(e V BC/V T. α F I SE = α R I SC = I S (3)
Experiment #8 BJT witching Characteristics Introduction pring 2015 Be sure to print a copy of Experiment #8 and bring it with you to lab. There will not be any experiment copies available in the lab. Also
More informationLecture 010 ECE4430 Review I (12/29/01) Page 0101
Lecture 010 4430 Review I (12/29/01) Page 0101 LTUR 010 4430 RVIW I (RAIN: HLM hap. 1) Objective The objective of this presentation is: 1.) Identify the prerequisite material as taught in 4430 2.) Insure
More informationDC and AC modeling of minority carriers currents in ICs substrate
DC and AC modeling of minority carriers currents in ICs substrate Camillo Stefanucci, Pietro Buccella, Maher Kayal and JeanMichel Sallese Swiss Federal Institute of Technology Lausanne, Switzerland MOSAK
More informationLecture 16 The pn Junction Diode (III)
Lecture 16 The pn Junction iode (III) Outline I V Characteristics (Review) Small signal equivalent circuit model Carrier charge storage iffusion capacitance Reading Assignment: Howe and Sodini; Chapter
More information12. Memories / Bipolar transistors
Technische Universität Graz Institute of Solid State Physics 12. Memories / Bipolar transistors Jan. 9, 2019 Technische Universität Graz Institute of Solid State Physics Exams January 31 March 8 May 17
More informationECE 340 Lecture 27 : Junction Capacitance Class Outline:
ECE 340 Lecture 27 : Junction Capacitance Class Outline: Breakdown Review Junction Capacitance Things you should know when you leave M.J. Gilbert ECE 340 Lecture 27 10/24/11 Key Questions What types of
More informationSample Exam # 2 ECEN 3320 Fall 2013 Semiconductor Devices October 28, 2013 Due November 4, 2013
Sample Exam # 2 ECEN 3320 Fall 203 Semiconductor Devices October 28, 203 Due November 4, 203. Below is the capacitancevoltage curve measured from a Schottky contact made on GaAs at T 300 K. Figure : Capacitance
More informationSOLUTIONS: ECE 606 Homework Week 10 Mark Lundstrom. Purdue University. (Revised 3/29/13)
ECE 66 SOLUTIOS: ECE 66 Homework Week 1 Mark Lundstrom (Revised 3/9/13) 1) In a forward biased P junction under low injection conditions, the QFL s are aroximately flat from the majority carrier region
More informationGATE SOLVED PAPER  EC
03 ONE MARK Q. In a forward biased pn junction diode, the sequence of events that best describes the mechanism of current flow is (A) injection, and subsequent diffusion and recombination of minority carriers
More informationLecture 04 Review of MOSFET
ECE 541/ME 541 Microelectronic Fabrication Techniques Lecture 04 Review of MOSFET Zheng Yang (ERF 3017, email: yangzhen@uic.edu) What is a Transistor? A Switch! An MOS Transistor V GS V T V GS S Ron D
More informationcollisions of electrons. In semiconductor, in certain temperature ranges the conductivity increases rapidly by increasing temperature
1.9. Temperature Dependence of Semiconductor Conductivity Such dependence is one most important in semiconductor. In metals, Conductivity decreases by increasing temperature due to greater frequency of
More informationLecture 210 Physical Aspects of ICs (12/15/01) Page 2101
Lecture 210 Physical Aspects of ICs (12/15/01) Page 2101 LECTURE 210 PHYSICAL ASPECTS OF ICs (READING: TextSec. 2.5, 2.6, 2.8) INTRODUCTION Objective Illustrate the physical aspects of integrated circuits
More informationProblem 9.20 Threshold bias for an nchannel MOSFET: In the text we used a criterion that the inversion of the MOSFET channel occurs when V s = ;2 F w
Prof. Jasprit Singh Fall 2001 EECS 320 Homework 11 The nals for this course are set for Friday December 14, 6:30 8:30 pm and Friday Dec. 21, 10:30 am 12:30 pm. Please choose one of these times and inform
More informationDiodes. anode. cathode. cutoff. Can be approximated by a piecewiselinearlike characteristic. Lecture 91
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
More informationLecture 15 OUTLINE. MOSFET structure & operation (qualitative) Review of electrostatics The (N)MOS capacitor
Lecture 15 OUTLINE MOSFET structure & operation (qualitative) Review of electrostatics The (N)MOS capacitor Electrostatics Charge vs. voltage characteristic Reading: Chapter 6.1 6.2.1 EE15 Spring 28 Lecture
More informationSection 12: Intro to Devices
Section 12: Intro to Devices Extensive reading materials on reserve, including Robert F. Pierret, Semiconductor Device Fundamentals Bond Model of Electrons and Holes Si Si Si Si Si Si Si Si Si Silicon
More information1st YearComputer Communication EngineeringRUC. 4 PN Junction
4 PN Junction We begin our study of semiconductor devices with the junction for three reasons. (1) The device finds application in many electronic systems, e.g., in adapters that charge the batteries
More informationHoles (10x larger). Diode currents proportional to minority carrier densities on each side of the depletion region: J n n p0 = n i 2
Part V. (40 pts.) A diode is composed of an abrupt PN junction with N D = 10 16 /cm 3 and N A =10 17 /cm 3. The diode is very long so you can assume the ends are at x =positive and negative infinity. 1.
More informationTutorial #4: Bias Point Analysis in Multisim
SCHOOL OF ENGINEERING AND APPLIED SCIENCE DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING ECE 2115: ENGINEERING ELECTRONICS LABORATORY Tutorial #4: Bias Point Analysis in Multisim INTRODUCTION When BJTs
More informationEE 230 Lecture 33. Nonlinear Circuits and Nonlinear Devices. Diode BJT MOSFET
EE 230 Lecture 33 Nonlinear Circuits and Nonlinear Devices Diode BJT MOSFET Review from Last Time: nchannel MOSFET Source Gate L Drain W L EFF Poly Gate oxide nactive psub depletion region (electrically
More informationLecture 15 OUTLINE. MOSFET structure & operation (qualitative) Review of electrostatics The (N)MOS capacitor
Lecture 15 OUTLINE MOSFET structure & operation (qualitative) Review of electrostatics The (N)MOS capacitor Electrostatics t ti Charge vs. voltage characteristic Reading: Chapter 6.1 6.2.1 EE105 Fall 2007
More informationSolar Cell Physics: recombination and generation
NCN Summer School: July 2011 Solar Cell Physics: recombination and generation Prof. Mark Lundstrom lundstro@purdue.edu Electrical and Computer Engineering Purdue University West Lafayette, Indiana USA
More informationLecture 12: MOS Capacitors, transistors. Context
Lecture 12: MOS Capacitors, transistors Context In the last lecture, we discussed PN diodes, and the depletion layer into semiconductor surfaces. Small signal models In this lecture, we will apply those
More information