Solid State Chemistry for Physics, Information Technology Devices and Energy

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Solid State Chemistry for Physics, Information
Technology Devices and Energy
Art Ramirez Director Device Physics Research Bell
Labs
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SSC and Condensed Matter Physics

• Superconductivity High, low, symmetry ??
• Quantum phase transitions
• Magnetism 1D, 2D, SDW
• Charge Density, Heavy Fermion, Ferroelectics

MgB2
Akimitsu et al Nature 2001

• Cross cutting themes
• Artificial spatial dimensionality
• Geometrical Frustration Spin Liquid, Spin Ice,
  Negative thermal expansion in ZrW2O8
• Mixed valence
• Multifunctionality

Paulings Ice Entropy
Ramirez et al, Nature 1999
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SSC and CMP Nations Status
Recent Major Discoveries based on
SSC Water-intercalated superconductivity H2ON
aCoO2 Berrys phase transport
Nd2Mo2O7 Multi-Ferroics from ISB magnetism
TbMnO3 Single-molecule metal Ni(tmdt)2 3d Heavy
Fermion Metal LiV2O4 MgB2 2-band
Superconductivity p-wave Superconductivity in
Sr2RuO4 Field-induced superconductivity in
?-BETS2FeCl4
Tanaka et al, Science 2001
Approach materials discovery by crystal growth
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New Materials Crystal Growth NRC Proposal

• Crystals are new materials with technological
  importance
• Much of CMP physics originates with NMCG
• NMCG funding suffered from reduction of
  industrial labs
• NMCG funding also not in line with major
  facility funding

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Moore's Law
10 um
Modern CMOS
Beginning of Submicron CMOS
1 um
Deep UV Litho
90 nm in 2004
34 Years of Scaling History
100 nm

• Every generation
• Feature size shrinks by 70
• Transistor density doubles
• Wafer cost increases by 20
• Chip cost comes down by 40
• Generations occur regularly
• On average every 2.9 years over the past 34 years
• Recently every 2 years

Presumed Limit to Scaling
10 nm
1 nm
1970
1980
1990
2000
2010
2020
Courtesy of D. Buss, TI
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SSC CMOS Roadmap

• Scaling CMOS to the End of Roadmap will require
  sophisticated condensed matter physics.
• Gate stack Atomic and electron orbital
  understanding of this complex material system
• Quantum behavior of carriers
• High perpendicular E field
• Stress
• Non-equilibrium Boltzmann transport
• Tunneling Gate insulator and Drain-to-Substrate
• Simulation
• Sophisticated condensed matter physics will also
  be required to invent and develop electronics
  beyond CMOS
• Single Electron Transistor (SET)
• Carbon Nano-tube (CNT)
• Molecular Electronics
• Spintronics
• Quantum Computing

SSC needed for new IT materials!
Courtesy of D. Buss, TI
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Micro- Electro- Mechanical Systems - MEMS

• Mechanical device functionality resonators,
  capacitors, microfluid, light control
• Silicon lithography high Q, materials
  integratable
• Materials compatible

MEMS microphone
Microcompass magnetometer
Lambda Router Mirror
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Solid-state Chemistry Information Device Physics

• - Colossal MR
• Ferroelectrics
• Multiferroics
• Organics

• Heterogeneous electronic phases, charge patterns
• Strongly coupled charge/ spin/lattice degrees of
  freedom

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Solid-state Chemistry Information Device Physics

• - Colossal MR
• Ferroelectrics
• Multiferroics
• Organics

CaCu3Ti4O12
Subramanian et al, 1999

SSC Challenge to combine local polarizability
and strong interactions, but to destabilize long
rage order
ZrW2O8
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Solid-state Chemistry Information Device Physics

• - Colossal MR
• Ferroelectrics
• Multiferroics
• Organics

TbMnO3 IC magnetism
Ni3V2O8 A Kagome Staircase

Kimura et al, Nature 2003

• large ME effect related to structures that
  induce IC magnetism
• Large opportunities for materials that combine
  AF, helical FM, and large polarizability

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Al, Cava, et al
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Multiferroics are Rare
Look at common mineral types that combine FE and
FM ions Spinel AB2O4 Perovskite ABO3
Pyrochlore A2B2O7 - hard to find A4 and B2,3.
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Solid-state Chemistry Information Device Physics

• - Colossal MR
• Ferroelectrics
• Multiferroics
• Organics

Structure of (EDT-TTF(CH2OH)2)2Mo6O19 From
Batail et al.

• Charge Transfer Salts
• Doping Carbon
• Carbon Nanotubes
• Plastic Electronics

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Solid State Chemistry and Energy
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Art Nozik, DOE Solar Energy Workshop, 2005
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Solid-state chemistry and energy

• Saving solid state lighting O and inO
• Conversion fuel cells, solar fuels,
  photovoltaics
• Storage primary and secondary batteries

• Issues for OLEDs conversion efficiency,
  operational life
• Small molecules improve triplet harvesting,
  spectral range

Luminous efficiency of monochrome OLEDS
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Solid-state chemistry and O-Solar Cells

• Materials issues similar to OLEDs injection
  efficiency, transport efficiency, emission
  efficiency
• Need new molecules that are strong,
  light-absorbing, band-gap and exciton level
  tunable
• C60 undergoes little structural distortion
  upon electron transfer

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Solid-state chemistry and energy control
Conversion High thermoelectric figure of merit
in Na0.75CoO2
Cava, Ong, Science 2004
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Solid-state chemistry and energy

• Transmission technologies superconducting
  electric cables
• Fuel stream purification technologies hydrogen
  separation membranes . How to make hydrogen?
• Fuel transportation containers, hydrogen
  storage materials
• Cuts across chemistry, materials science,
  chemical engineering, mechanical engineering
• Hybrid Organic/Inorganic

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Self-Assembled Materials and Organic Electronics

• Potential Organic Materials Advantages
• Printable/manufacturable
• Flexible
• Multi-functional materials/ molecular design (i.
  e. low-dielectric constant with high EO
  coefficient)
• Low-cost

drain
Market Potential - Flexible displays -
Smart Tags - Photovoltaics - 10B in 10
years - Lucent has 25 patents
0.1 mm channel
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TFT semiconductor Single crystal insulator

• - Polycrystalline thin film transistors
• Semiconductor spun on or evaporated
• Almost all of plastic electronics
• Naturally occurring free-carrier density 1017
  carriers/cm3 ?

Tetracene
3 mm
Yang et al, APL 2002

• ?Single crystals grown from vapor transport or
  melt
• Insulating, free carrier density 10-12
  carriers/cm3
• ? No fundamental understanding of doping or
  trapping in OFETs
• Similar situation in oxides

Tetracene single crystal
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Surface States in Single Crystals OFETs
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The Role of Single Crystals for Organic
Electronics

• Single Crystal FETs
• Easily fabricated
• High purity
• Address issues of relevance for plastic systems
  grain boundaries, deep traps, doping, reliability

pentacene

• Purity
• Commercial stock extremely dirty
• E.g. in pentacene (to left) have few dihydra,
  and quinone impurities
• Need e.g. a pilot manu- facturing program

Palstra group, APL 2004
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Identify individual H-related traps in pentacene
A
A
C
Ea 0.21 eV
C
Au pads on a Pentacene crystal
Ea 0.55 eV
D. V. Lang et al, PRL, 2004
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Crystal FETs from many different molecules
C. Kloc, R. Zeis
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PERIODIC TABLE OF THE ORGANICS
Symbol
picture
Band gap
B
N
6 eV
5 eV
Name
Benzene
Napthalene
T
C
A
P
3.9 eV
3.1 eV
2.2 eV
Du
CH3
CH3
Tetracene
Pentacene
Coronene
Anthracene
CH3
CH3
Py
Cl
Durene
Corannulene
Perylene
Ru
Tc
ET
. . .
Vi
C60
C2n
TCNQ
BEDT

2.3 eV
Fullerite
Fullerites
Blue melts at atmospheric pressure
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Bell Labs Crystal Growth Archive Many samples
from both our archives and from ongoing research
projects are available for measurement by request
http//www.bell-labs.com/research/crystal.html
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