ece 331: introduction to materials for electrical engineersringel/331...

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ECE 331: Introduction to Materials for Electrical Engineers Course Objective... Introduce fundamental concepts in Materials Introduce fundamental concepts in Materials Science and how they are used in ECE You will learn about: material structure how structure dictates properties • how electronic & physical properties are related how electronic & physical properties are related This course will help you to: • use materials properly use materials properly realize new design opportunities with materials understand the physics of semiconductor devices ECE331 Wi11 lecture 1

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ECE 331: Introduction to Materials for Electrical Engineers

Course Objective...Introduce fundamental concepts in MaterialsIntroduce fundamental concepts in MaterialsScience and how they are used in ECE

You will learn about:• material structure• how structure dictates properties• how electronic & physical properties are related• how electronic & physical properties are related

This course will help you to:• use materials properly• use materials properly• realize new design opportunities with materials• understand the physics of semiconductor devices

ECE331 Wi11 lecture 1

ECE 331 – Intro to Materials for ECE

Materials in ECE are: semiconductors, metals (e.g. Al t t ) l ( l t f LED )Al contacts), polymers (e.g. encapsulants for LEDs) and insulators (ceramics such as silicon dioxide in FETs))

Materials in ECE are single crystals, polycrystals, h l d t tamorphous layers and nanostructures

Si (silicon) is NOT the only semiconductor (thoughSi (silicon) is NOT the only semiconductor (though Si electronics is the world’s largest manufacturing industry), but it is the most important one and will

i !

ECE331 Wi11 lecture 1

remain so!

ECE 331 – Intro to Materials for ECE

III-V examplesGaAsInPInAsAlGaAsAlGaAsInGaAsInGaAsPG NGaNInGaN

ECE331 Wi11 lecture 1

III - V•Know your periodic table!•Find your old chemistry notes!

Materials Roadmap for Device Technologies: the Bandgap vs Lattice Constant Relationship

III-V electronics

ECE applications areexpanding acrossIII V electronics

CD LasersFiber pump lasersSpace solar

expanding across this entire space!

CMOS BiCMOSCMOS, BiCMOS,Terrestrial solar,Power CMOS

TelecommOptoelectronicsthermophotovoltaics

ECE331 Wi11 lecture 1

TECHNOLOGY ROADMAPS: New Age for ECE Materials and opportunities

• Electronics:

Roadmaps are calling for unusual properties not obtainable using conventional materials or processes• Electronics:

- Nanoscale patterning- optical interconnects- speed enhancing materials

• Optoelectronics:Optoelectronics: - tunable light emission/detection wavelengths- seamless integration with electronic systems

• Alternative Energy:- clean, renewable, cheap, safe, autonomous

ECE331 Wi11 lecture 1

- Biocompatiblity and medicine

The Materials Selection Process

1. Pick Application Determine required PropertiesProperties: mechanical, electrical, thermal,magnetic, optical, deteriorative.

2. Properties Identify candidate Material(s)Material: structure, composition.

3. Material Identify required ProcessingProcessing: changes structure and overall shapeProcessing: changes structure and overall shapeex: casting, sintering, vapor deposition, doping

forming, joining, annealing.

ECE331 Wi11 lecture 1

ELECTRICAL• Electrical Resistivity of Copper:

Adapted from Fig. 18.8, Callister 7e.6 g(Fig. 18.8 adapted from: J.O. Linde,Ann Physik 5, 219 (1932); andC.A. Wert and R.M. Thomson,Physics of Solids, 2nd edition,McGraw-Hill Company, New York,1970 )

4

5

y, r

m)

1970.)

2

3

esis

tivit

0-8

Ohm

-

1

2

Re (10

0

• Adding “impurity” atoms to Cu increases resistivity.

T (°C)-200 -100 00

ECE331 Wi11 lecture 1

• Deforming Cu increases resistivity.

THERMAL• Space Shuttle Tiles:

--Silica fiber insulationoffers low heat conduction

• Thermal Conductivityof Copper:

decreases when you add zinc!offers low heat conduction. - decreases when you add zinc!

ity

400Adapted from chapter-opening photograph,

ondu

ctiv

i/m

-K) 300

200

Chapter 19, Callister 7e. (Courtesy of LockheedMissiles and SpaceCompany, Inc.)

herm

al C

o(W

/

100

00 10 20 30 40

Adapted fromFig. 19.4W, Callister 6e. (Courtesy of Lockheed Aerospace C S

Adapted from Fig. 19.4, Callister 7e.(Fig. 19.4 is adapted from Metals Handbook: Properties and Selection: Nonferrous alloys

Composition (wt% Zinc)Th 0 10 20 30 40

ECE331 Wi11 lecture 1

Ceramics Systems, Sunnyvale, CA)(Note: "W" denotes fig. is on CD-ROM.)

p yand Pure Metals, Vol. 2, 9th ed., H. Baker, (Managing Editor), American Society for Metals, 1979, p. 315.)

100mm

MAGNETIC• Magnetic Permeability

vs. Composition:• Magnetic Storage:

--Recording medium--Adding 3 atomic % Si

makes Fe a betterrecording medium!

is magnetized byrecording head.

g

zatio

n Fe+3%Si

F

Mag

netiz Fe

Adapted from C.R. Barrett, W.D. Nix, andA.S. Tetelman, The Principles ofEngineering Materials, Fig. 1-7(a), p. 9,

Fig. 20.23, Callister 7e.(Fig 20 23 is from J U Lemke MRS Bulletin

Magnetic FieldM

ECE331 Wi11 lecture 1

Engineering Materials, Fig. 1 7(a), p. 9,1973. Electronically reproducedby permission of Pearson Education, Inc.,Upper Saddle River, New Jersey.

(Fig. 20.23 is from J.U. Lemke, MRS Bulletin,Vol. XV, No. 3, p. 31, 1990.)

OPTICAL• Transmittance:

--Aluminum oxide may be transparent, translucent, oropaque depending on the material structure.

single crystalpolycrystal:low porosity

polycrystal:high porosityg y p y g p y

Adapted from Fig. 1.2,Callister 7e.(Specimen preparation,P.A. Lessing; photo by S. Tanner )

ECE331 Wi11 lecture 1

Tanner.)

Photovoltaics and the role of materials

ECE331 Wi11 lecture 1

ECE331 Wi11 lecture 1

Conversion of radiant heat to electricity: Thermophotovoltaics

InterconnectGrid Finger

Front Contact

p

n InPAs window

p InPAs BSF

S i I l ti I P

n InPAs Bufferp/n InGaAs TJ

n/p InGaAsEmitter/Base

Semi-Insulating InP

SiN/Gold Back Surface Reflector

23

SEM Micrograph Of Processed TernaryMIM Structure

1920212223

ficie

ncy

(%)

26.7°C26.7°C

25.6°C

• Efficiency ~18%

• With addition of a a front surface filter

1516171819

Syst

em E

ff25.6°C

surface filter – 0.9 W/cm2 power density- h = 20.6% at a radiator

temperat re of 1058°C

ECE331 Wi11 lecture 1

850 900 950 1000 1050 1100

Radiator Temperature (°C)

temperature of 1058°C.

Wide Bandgap Semiconductors – GaN: Energy-Efficient Solid State Lighting (SSL)gy g g ( )

• Al-Ga-In-N spans uv-blue-green-red-near ir spectrum

50% of elec used by lighting:

National SSL Initiative: by 2020:• save $115B

ECE331 Wi11 lecture 1

50% of elec.used by lighting: • eliminate 258M metric ton of C emission

SUMMARY

• Use the right material for the job

Course Goals:

• Use the right material for the job.

• Understand the relation between properties,structure, and processing.

• Recognize new design opportunities offered• Recognize new design opportunities offeredby materials selection.

• Appreciate the relationship between devices• Appreciate the relationship between devices, their characteristics and their constituent materials

ECE331 Wi11 lecture 1