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Outline

AlamECE‐606S09 2

1.  LookingBack:Quickreviewofwhatwelearned2.  Newdevices–lookingahead

a.  flexibleelectronicsb.  solarcells,andc.  Nanobiosensors

3.  Conclusion

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OutlineoftheCourse

AlamECE‐606S09 3

Foundaon

inPhysicsDevice‐specific

systemdesign

MOSFETs(3wks)

QuantumMechanics

+

StaPsPcal

Mechanics

Transport

EquaPons

PhysicalPrincipleof

deviceoperaon

Resistors(5wk)

Diodes(3wk)

Bipolar(3wk)

Applicaonspecific

deviceoperaon

TFTfor

Displays

CMOS‐based

Circuitsform

LASERSfor

DiskDrives

MEMSfor

Readheads

EE606

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Quantum,StaPsPcalMechanicstoDevices

AlamECE‐606S09 4

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AQuickSummary

AlamECE‐606S09 5

E

k

k

E

DOS

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Grapheneandothermaterials..

6

E

DOSwww.magnet.fsu.edu

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OnFermiFuncPons

7

k

E

g(E)

E

Energy‐Band DensityofStates

Importance of correlation – free vs. localized states

E1

E2

E3

http://www.physics.mcgill.ca/SPM/JEOL/

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EquaPonstosolve…analyPcal/numericalapproach

AlamECE‐606S09 8

Band‐diagram

DiffusionapproximaPon,

Minoritycarriertransport,

Ambipolartransport

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Short‐cuttoBand‐diagram

AlamECE‐606S09 9

… is equivalent to solving the Poisson equation

Vacuumlevel

EC

EV

EF

c2

c1

Neutral Neutral

Space

Charge

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MinorityCarrierDiffusion

AlamECE‐606S09 10

F  pF n

q(V bi -V  A ) 

-V  A

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ThermionicEmission&HeterostructureDisconPnuity

AlamECE‐606S09 11

VAEC‐EF

q(Vbi‐VA)

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SmallSignalACResponse

AlamECE‐606S09 12

RS

G

CD

CJ

x

Δρ

x

Δρ

VA<0

VA>0

np

x

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Digital,LargeSignalApplicaPons

AlamECE‐606S09 13

V

ln(I)

‘1’to‘0’

‘0’to‘1’

AV‘1’

‘0’

‐0.1IR

‐IR

IF

ts

t rr 

tr

i(t)

t

VA(t)

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LargeSignalChargeControlModel

AlamECE‐606S09 14

Areaunderthe

curve@given

me

n(x,t)

x

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FewconceptsforDeviceAnalysis

AlamECE‐606S0915

Equilibrium DC Smallsignal

LargeSignal

Diode Band‐diagram diffusion dn/dt~jwn Charge‐

control

Schottky Band‐diagram TE JuncPon

capacitance

Majority

transport

BJT/HBT  Band‐diagram diffusion

/TE

dn/dt~jwn Charge‐

control

MOSCAPMOSFET 

2Dband‐

diagram

Dri/TE MOS

capacitance

Charge‐

control

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GrandChallengesinElectronics

AlamECE‐606S0916

1906‐1950s 1947‐1980s 1960‐unPlnow

Vacuum

TubesBipolar MOSFET

Spintronics

BioSensors

Displays….

Now??

?

1900192019401960198020002020

     T    e    m    p

TubesBipolar MOS

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EmergenceofMacroelectronics

Area

small medium large

   P  e  r   f  o  r  m  a  n  c  e

   l  o  w

  m  e

   d   i  u  m 

   h   i  g   h

mesoporous

NanoNet Poly-Si 

Polymers

Flexible ElectronicsEnergyBiosensors

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ThinFilmOrganicTransistors

18

www.faculty.iu-bremen.de/dknipp/group/research.htm 

M.G. Kanatzidis, Nature, 428, 2004.

pentacene

Sonydisplay180x120pixels

Canyoudrawtheband‐diagram? Whattypeoftransporttheorywouldyouuse? Wouldyoubeabletousenumericalsimulators

fromnanohub.orgtoexploretheTFT? 

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FourprocessesofaSolarCell

Sideview Band‐diagram

Electron-hole recombination before dissociationat the junction makes it a poor cell …

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electron

Holes

NanostructuredSolarCells

mixed layers

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An array …

Time

   C  o  n   d  u  c   t  a

  n  c  e   (   G   )

DG

t s response time

G0

Individual sensor Capture Probe

C

A

G

A

T

Q1

C

A

G

A

T

T

T

A

C

G

Q2

Q1

Optical detection schemes

Surface Plasmon Resonance

Fundamentalsofnanobiosensing

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Conclusions:RobotsandJellyfish

Life at the edge of equilibrium thermodynamics isvery successful ; Shouldn’t our electronics be the same ?

energy

Resources

reusability

function

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Summary

AlamECE‐606S0923

1)  Electronicsremainsavibrantareaandtherehavebeen

manyinnovaPonbeyondtheclassicalelectronicdevices.

2)ItislikelythatelectronicswillfindapplicaPonsbeyond

compuPngandcommunicaPon.Nothingnew,actually!

Electronicsstartedwithelectricalmachines,branched

intocommunicaPon,radar,thentocompuPng;future

applicaPonsinenergyconversion,healthcareare

anPcipated.

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Acknowledgement

AlamECE‐606S0924

1)  MohammadAsaduzzmanforhelpwithfiguresandHW.

2)  Mr.JoeCychoszandRickDesuerforhelpingus

videotapetheselecture.

3)  NetworkofcomputaPonalNanotechnologyforresources

andIntelforfinancialsupport.

4)  rofs.M.LundstromandS.Daafordiscussions.

5) StudentsfrompreviousEE606classeswhoenduredthecoursewithoutlecturenotes.

6)  Andtoyou…forshowingupat7:30ammorningclass!