EE 330 Lect 19 Spring 2011

EE 330 Lect 19 Spring 2011 - EE 330 Lecture 19...

Info iconThis preview shows pages 1–20. Sign up to view the full content.

View Full Document Right Arrow Icon
EE 330 Lecture 19 Characteristics of Finer Feature Size Processes Bipolar Process
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Basic Devices and Device Models • Resistor • Diode • Capacitor • MOSFET • BJT
Background image of page 2
Bipolar Junction Transistors • Operation • Modeling
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Carriers in Doped Semiconductors n-type p-type
Background image of page 4
Carriers in Doped Semiconductors V I V I Current carriers are dominantly electrons Current carriers are dominantly holes Small number of holes are short-term carriers Small number of electrons are short-term carriers
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Carriers in Doped Semiconductors Majority Carriers Minority Carriers n-type electrons holes p-type holes electrons
Background image of page 6
Carriers in MOS Transistors Consider n-channel MOSFET Saturation Region Triode Region Channel
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Carriers in MOS Transistors Consider n-channel MOSFET Saturation Region Triode Region Carriers in electrically induced n-channel are electrons
Background image of page 8
Carriers in MOS Transistors Consider p-channel MOSFET Saturation Region Triode Region Channel
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Carriers in MOS Transistors Consider p-channel MOSFET Saturation Region Triode Region Carriers in electrically induced p-channel are holes
Background image of page 10
Carriers in MOS Transistors Carriers in channel of MOS transistors are Majority carriers
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Bipolar Transistors npn stack pnp stack E E B B C C With proper doping and device sizing these form Bipolar Transistors pnp transistor B C E npn transistor B C E Bipolar Devices Show Basic Symmetry Electrical Properties not Symmetric Designation of C and E critical
Background image of page 12
Bipolar Transistors pnp transistor B C E npn transistor B C E n-channel MOSFET p-channel MOSFET In contrast to a MOSFET which has 4 terminals, a BJT only has 3 terminals
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Bipolar Operation npn stack E B C Under forward bias current flow into base and out of emitter Consider npn transistor Current flow is governed by the diode equation Carriers in emitter are electrons (majority carriers) When electrons pass into the base they become minority carriers Quickly recombine with holes to create holes base region Dominant current flow in base is holes (majority carriers)
Background image of page 14
Bipolar Operation npn stack E B C Under forward BE bias and reverse BC bias current flows into base region Consider npn transistor Carriers in emitter are electrons (majority carriers) When electrons pass into the base they become minority carriers When minority carriers are present in the base they can be attracted to collector
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Bipolar Operation npn stack E B C Consider npn transistor If no force on electron is applied by collector, electron will contribute to base current F 1
Background image of page 16
Bipolar Operation npn stack E B C Consider npn transistor If no force on electron is applied by collector, electron will contribute to base current Electron will recombine with a hole so dominant current flow in base will be by majority carriers F 1
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Bipolar Operation npn stack E B C Consider npn transistor When minority carriers are present in the base they can be attracted to collector with reverse-bias of BC junction and can move across BC junction F 1 F 2
Background image of page 18
Bipolar Operation npn stack E B C
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 20
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 01/31/2012.

Page1 / 52

EE 330 Lect 19 Spring 2011 - EE 330 Lecture 19...

This preview shows document pages 1 - 20. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online