CMI Tiny Tech Meeting

15.00 Welcome 5 mins Ted Acworth (MIT)

15.05 Introduction & Review of Projects 40 mins

o MEMs: material design and processing for MMAsProf W I Milne (CU)Prof D Boning (MIT)

o Optical properties of nanoscale arraysProf K A Nelson (MIT)Prof J F Scott (CU)

o Magnetoelectronic devicesProf C A Ross (MIT)Prof J A C Bland (CU)

o Ultimate Polymer: Carbon nanotube enabled materialsProf A H Windle (CU)Prof M C Boyce (MIT)

15.45 An outline of CMI’s rationale for a TinyTech KIC 10 mins Ted Acworth

15.55 Conclusions from meeting and development of action plan

o A list of grand vision ideas

o A list of potential collaborators

o Who should be included from Industry / Government

o Should CMI hire a KIC Manager to go after fundingsources

o Next steps

30 mins

All

16.25 Closing remarks 5 mins Ted Acworth

16.30 Networking / refreshments 30mins

17.00 End of meeting

Meeting Agenda:

1 3

CMI Project Review:

Project Name: MEMS Research: Materials Design and Processing

for MMAs Number: P/059

Report Period 05/2004-10/2004

Page 1

MEMS Research: Materials Design and Processing for MMAs

Cambridge PI’s: Prof. Bill Milne, Prof. Norman Fleck, CU Engineering Dept. MIT PI: Prof. Duane Boning, EECS (replaces Prof. Spearing)

Co-investigators: Flewitt, Moore, Seshia, Schmidt, Sutcliffe, Thompson, Wardle, Williams

• Objective: To establish an intellectual community at Cambridge, focused on the development of MicroElectroMechanical Systems (MEMS), introducing new materials, processes and design methods.

• Intended Outcomes: Establishment of intellectual community at Cambridge, linked to MIT, built upon existing strengths at CUED. Generation of research results, and IP in areas of new materials, processes, material/process/sensor/actuator selection, actuator/sensor optimization, test methods for MEMS/MMA’s

Page 2

Progress In Past Six Months (beyond technical)

• Important activities, collaborations: – Collaborations

• Mark Spearing has visited CUED several times during this period and has now moved to Southampton University

• Carl Thompson has visited CUED during this period• Weekly MEMS meetings continuing at CUED and MIT• Discussions with Richard Syms I.C, Paul Kirby Cranfield, Julian Gardner

Warwick University re interactions• Hayden Taylor (CU@MIT exchange ’02-03) completed MEng at CU (’04)

with D. Moore, has started Ph.D. at MIT in Fall ‘04

– Several papers published or in preparation with joint authorship between CUED and MIT

– Web Site has been set up www-g.eng.cam.ac.uk/edm

Page 4

Progress In Past 6 Months (technical)• Sutcliffe et al working on CMP.• Luo, Flewitt, Milne and Chua have continued work on DLC MEMS growth, material

development and device design and fabrication. Also the DLC work has been further extended by Luo et al to optimise the Ni/DLC bimorph actuated normally closed microgrippers- modified for Bio applications

• Flewitt and Moore worked on Micro-test system development.• Tribological behaviour of MEMS materials by K S Faszer and John Williams . • Chua, Milne et al investigated DLC for SAW devices. • Fleck , Chua et al worked on microshear testing facility- new• Flewitt and Ahsan worked on deployable locks based on a variety of material systems.• Seshia continued work on MEMS devices specifically, micromechanical resonator

oscillators for wireless transceiver and sensor applications, micromechanical biosensors, and inertial sensors

• Published guidelines/protocols for direct wafer bonding (K. Turner Ph.D. May ‘04)• Boning continued work on DRIE wafer-level and pattern-dependent models• Wardle joined effort and worked on piezoelectric vibrational energy harvesters- new

Page 5

New Material Development - DLC DevicesLuo, Milne, Flewitt, Spearing and Fleck Pages 14 & 15

• Creation of bimorph structures to create normally closed grippers

• Combination of DLC and electrolytic Ni

• Thermal actuation by resistance heating

• Builds on earlier work on electro-deposition, DLC, micro-mechanical testing and modeling

• Potential applications for bio-MEMS cell capture

Bio-compatible structure_1

Ni

DLC

Polymer

L

d1

d2

d3

0.0

20.0

40.0

60.0

80.0

100.0

120.0

0 1 2 3 4 5 6 7

Input Voltage (V)

Displacement (µm)

Bi-layer SU8 Tri-layerPolyimide Tri-layer Poly. (Bi-layer)Poly. (SU8 Tri-layer) Poly. (Polyimide Tri-layer )

A thin polymer on a bimorph structure does not change the displacement of the device, but acts as a coating layer

DLC/Ni:100/500nm

Polymer:100nm

Stress: 6GPa

Variable capacitor with DLC insulatorPage 17

(c)(d)

(e) (f)

Cantilever type

Bridge type

DLC as insulator

Micro Piezoelectric Vibration Energy Harvester (MPVEH)

Brian Wardle, MIT Aero/Astro

• Objectives– Power for wireless sensor node applications such

as infrastructure & structural health monitoring (SHM), RFID tags, homeland security, etc.

– MEMS fabrication development– Low-level ambient sources targeted– Predictive design tools

• Needs– Pervasive power from pervasive ambient sources– Wireless sensor’s power trending down, currently

in 10-100s of W range– Voltage levels on order of Volts (3V std.)

Page 18

Other Items

• Developments worth publicizing: Nano/MEMS M.Phil now up and running.

• Modifications to statement of work and/or funding: essentially unchanged from original proposal.

• Expected financial profile: near constant spend rate to end of project. All staff now in place.

Page 21

Plans For Next Six Months• Expected activities, collaborations:

– Continued interchange of personnel, ideas– Increased interaction with industry as project thrusts yield results (wafer bonding/CMP,

DRIE, materials selection)– Increased focus on devices in research

• Integration of thermal grippers into practical devices - need to discuss further with Ted Acworth

• Expected milestones/deliverables:– Publish guidelines/protocols for DRIE (MIT)

– Challenges and/or Issues To Address• Problem/Concern:

– Continuation of MEMS activity beyond CMI funding (one year to go)• Plan for resolution:

– CU side actively looking for other funding sources for CU MEMS activities, some EU and EPSRC funding obtained, other sources sought

– Funding for MEMS at CUED is continuing to increase• How CMI can help

– KIC -Tinytech?Page 22

Project 1/97 slides

CMI Project Review:

Optical Properties of Nanoscale Arrays

CMI-001

Fabricate Voltage-Tunable Photonic Devices

Filled with Ferroelectrics

P/097

May – Nov 2004

Optical Properties of Nanoscale ArraysVoltage-Tunable Photonic Devices

Cambridge PI : Prof. James F. Scott, Earth Science Dept.MIT PI : Prof. Keith A Nelson, Chemistry Dept.• Brief Description of Project:Fabricate micron- or submicron-arrays of voltage-tunable

ferroelectric devices consisting of two-dimensional patterns of high refractive index rods

Characterize GHz-THz dielectric responses through "polaritonics" measurements w/ micron spatial resolution

• Summary of Intended Outcomes:Delivery and test of a small number of prototype devicesPrototype apparatus for GHz-THz dielectric metrology

Progress In Past Six Months•Important activities, collaborations:

• Investigation of Pd-acetate based precursors for electroding

• Continued collaboration with Finlay Morrison (Royal Soc. URF)

• Continued discussions with Company X – exploratory pro bono experiments underway for microfluidics (ink-jet printers)

• Contractual discussions with Company Y – drug delivery systems (monodisperse inhalers)

• Contractual discussions with Company Z – venture capital company offering an initial £100,000.

• Fabrication of 10-20 micron polaritonics structural elements

• Direct imaging of polariton fields in 10-20 micron structures

• FDTD simulations of polariton propagation in small structures

• Study of candidate materials for smaller polaritonics length scales

• Basis of ~ 50 kV/cm THz electric fields established

•Milestones achieved:• Alternate electrode material (Ru) sourced : DER (2,4-

Dimethylpentadienyl)(ethylcyclopentadienal)ruthenium• Nanotubes fabricated using both Trento and KTH substrates

•Deliverables completed:• Nanotube arrays from Trento and KTH substrates• Thin film polaritonics paper submitted for publication

Polariton bandgap movie

THz polaritonic bandgap materials fabricated in FE films

by fs laser machining

Can control THz polariton wave propagation, focusing

Will reach 1-5 m feature sizes

Plans For Next Six Months• Expected activities, collaborations :

• Use of ruthenium for electroding (DER from Tosoh Corp)• Receive delivery of Rapid Thermal Processor• Continuation toward smaller length scales, higher THz fields• Renewed attempt at THz polaritonics in FE nanotubes

• Expected milestones:• Nanotubes with concentric electrode structure (Pd/SBT/Ru)• Investigate electrical properties of single electroded nanotube• Addressable array of electroded nanotubes• 1-5 micron polaritonics length scales• 50 kV/cm THz fields

• Expected deliverables:• Fabrication of single electroded nanotube and evaluate piezoelectric response• Fabricate a small (4x4, 16 bit) array of addressable nanotubes • Publications on simulations & THz measurements in small structures

Other Items• Modifications to statement of work and/or funding:

• Expected financial profile:• MIT is out of funds!

• Anything else:• PDRA Dr Veronika Kugler successfully attained permanent post

in UK industry (Carl Zeiss SMT Ltd)• JFS has given 5 invited talks in the last 6 months: MAGEL (La

Rochelle, July), Eur. Physical Soc (Prague, Aug), Int. Conf. On Domains (Tsukuba, Aug), Eur. Conf on Appl of Polar Dielectrics (Liberec, Sept), NATO Adv Research Workshop (Lvov, Oct).

PR / Communications / Events

• Any previous press interest in your project? By whom? What media?• Cambridge Univ. Research Services expects a press release by

March or April.

• Upcoming events, major publications, noteworthy dates in the next six months:• No publications on Cambridge work due to proprietary/patent

reasons.• Publications on simulations & THz measurements in small

structures

• Do you need any help with your PR / communications / event planning?

Challenges And/or Issues To Address• Problem/Concern:

• The deposition of Pd electrodes has turned out to be a complex materials science problem. Although Pd-acetate is a confirmed methodology (Steinhart, 2003), the processing does not normally produce an atomically flat, uniform sheet of metallic Pd as the electrode; rather, it yields crystals (see attached figures). Although these do conduct, in our judgment they are not suitable for commercial devices.

1.0 μm 0.5 μm

Figure. Pd particles formed by thermal decomposition of a Pd-acetate thin film

Challenges And/or Issues To Address• Plan for resolution:

• Ongoing investigation of incorporation of co-polymer (e.g. polyethylene glycol) to improve Pd microstructure

• We have already taken delivery of a new Ru precursor chemical [Ruthenium-DER] from Tosoh (Tokyo) which has been shown in an unpublished Samsung-Tokyo collaboration to produce superior electrodes in DRAM trenches, compared with Pd.

• How CMI can help:• This electroding problem has caused a 3-month delay

and associated unbudgeted costs.

Project 61 slides

Magnetoelectronic Devices Cambridge PI: Prof. J. Anthony C. Bland, Cavendish Lab.

MIT PI: Prof. Caroline A. Ross, Materials Science and Engineering Department

MIT Co-PI: Dr. Jagadeesh S. Moodera, Francis Bitter Magnet Laboratory

Brief Description of Project:To develop the technology of magnetoelectronic devices. This will

be achieved by work on two specific devices : an MRAM (magnetic random access memory) and a spin-diode. To select at least one of these devices for prototyping. To interact with potential manufacturers in the UK to bring a magnetoelectronic device to market.

500 nm

Top: Made using evaporation: Co/Cu/NiFe ring, Au/Ti metal

Bottom: Made using sputtering: 20nm NiFe ring, Ta/Cu/Ta metal

2 um2 um

MRAM prototypes based on Elliptical Ring cells

F. J. Castaño, C. A. Ross

20 nm NiFe/10 nm FeMn rings of different widths: note exchange bias

Incident beam

Two major switching routes

• Vortex state has same circulation (+ or -) on both downward and upward field sweeps

Observed transitions:O-V = onion-vortex, V-O = vortex-onion

Determination of vortex state circulation in a single ring during one applied field cycle

Sinusoidal field

T.J. Hayward, T.A. Moore, CU

NiFe ringdout = 5 mdin = 3 m

-400 -200 0 200 400

Applied field (Oe)

+

+

Hc1

Hc2

-

-Hc1

Hc2

O-V V-O

V-O O-V

Focused Kerr microscopy

Applied field

Design for a ring sensor element

Bead

GMR ring stack

Fixed layer: onion stateFree layer: has vortex state at remanence

• Bead absent: free layer oscillates between onion and remanent vortex state• Bead present: switching to onion state is suppressed• Measured as a change in the MR

T.J. Hayward, J. Llandro

Ring d = 2 mBead d = 2 m

Mbead = 3Hext

1.0051.01500.20.4Anti - Aligned OnionVortex 1Vortex 2Aligned OnionbRelative resistance

Varaiation of relative resistance with b for all four possible states of the free layer

Resistance vs. current contact position

Max separation

Sensor

• Signal amplitudes up to ~1 mV

External field distn: bead not presentExternal field distn: bead on top of ring

Spin-injection into Silicon by spin filtering using EuO

Ag or Y EuO

Si

2nm

Si spin diffusion channel2m x 2m x 10m,SOI wafer, photolith. & RIE

spin-detectorspin-injector

Spin-injector, detector, contacts by e-beam lithography

EuO allows efficient spin injection

Future possibilities for TinyTech KIC

A TinyTech KIC could be focussed towards developing hybrid nanoscale devices - those incorporating electronic, magnetic and/or optical materials, allowing a range of new functionalities. The group might select several examples for collaborative development.

Examples:

Magnetoelectronic memory, or Sensor for biofunctionalized beads, based on magnetic rings; Spin transistor; Optically addressed ferromagnet/semiconductor memory element or processor; CNT-based transistor …

Project 38 slides

Carbon Nanotube Enabled Materials:CMI Program Summary, Nov. 2004

M.C. Boyce, R.E. Cohen, J. Robertson, A.H. Windle, K.K. Gleason, G. McKinley, D.M. ParksM. Hamm, Q. Li, M. Motta, A. Pantano, M. Garg, K. Lau, C. He, B. J. Bico, V. Arnim, Kleinsorge, S

Hofmann, K Teo, M Cantoro

SynthesisSynthesis Patterned arrays and vertically aligned CNT coatings Patterned arrays and vertically aligned CNT coatings Properties of directly spun CNT fibreProperties of directly spun CNT fibre

Modeling Modeling Deformation Effects on Electrical ConductivityDeformation Effects on Electrical ConductivityEquivalent Orthotropic Model of MWNTEquivalent Orthotropic Model of MWNT

Properties of Vertically Aligned CNT CoatingsProperties of Vertically Aligned CNT CoatingsNanoindent and Nanoscratch BehaviorNanoindent and Nanoscratch BehaviorWetting BehaviorWetting BehaviorHeat Transfer BehaviorHeat Transfer Behavior

CNT Polymer NanocompositesCNT Polymer NanocompositesStable suspension of SWCNTsStable suspension of SWCNTsRheology of tube-filled melts and suspensionsRheology of tube-filled melts and suspensionsMechanical behavior of thermoplastic compositesMechanical behavior of thermoplastic composites

• Large area, selective growth. Not bulk growth

• Ni catalyst.

• DC plasma

• C2H2:NH3 1:3, 60 mbar pressure

• Bias voltage aligns CNTs (600V)

• Selective growth. Nanotubes only grow where there is catalyst (Ni)

• NH3 etches away unwanted a-C

Plasma Enhanced Chemical Vapour Deposition

• Side view

• Patterned catalyst gives selective growth• Shadow mask or• Lithography

Patterned Growth

Prior Work on CMI Project: Nanoindentation on Prior Work on CMI Project: Nanoindentation on Vertically Aligned Carbon Nanotube (VACNT) Vertically Aligned Carbon Nanotube (VACNT) ForestsForests

Typical indentation force-penetration curveTypical indentation force-penetration curve from nanoindentation testsfrom nanoindentation tests

0 200 400 600Penetration (nm)

0

2000

4000

6000

8000

Indentationforce(nN)

Produced by PECVD method

Dimensions can be better controlled

Applications: field emission devices, hydrophobic coatings, composite materials

Continuous wind upFeedstock

Wind-up

HOT ZONE HOT ZONE

“Vertical”

Feedstock

Wind-up

HOT ZONE HOT ZONE

“Horizontal”

Ethanol*ThiopheneFerrocene

1100 to 1200 °CH2 carrier gas

Multi wall CNTs:Microstructure of the fibre products

Fibre diameter of 20 to 50 m

1m

m50 m

0 45 90 135 180 225 270 315 360

Angle (¡)

Intensity (A.U.)

Experimental data

Fitted curveImageanalysis

Mechanical Properties

GPam

N

m

g

g

mN=

?=

?∗

??−

9263

3

11

1

km

gTEX =

The range of diameters along a fibre occurs

due to differences in the local packing density

of nanotubes and/or instabilities in the gas-

phase reaction.

100 m

StressDensityTEX

Force=∗

0

0

1 16 18 202 4 6 8 0 12

12

i

140

G

Pa

s

1.0

Strain %

Nematic Dispersion

50 m

Optical micrographs of carbon nanotube dispersions, imaged in reflected light with crossed polars.

Song, W. Kinloch, I.A. and Windle, A.H. Science, 302, 1277 (2003)

–1/2 Disclination

Scanning electron micrograph showing details of orientation around a disclination of strength –1/2.

New UK Collaborations arising:-

Synthesis and processing of CNT

(i) “Canape” EU funded 8 M EurosCambridge University+ 14 partners in France, Germany, Belgium, Switzerland and Italy

(ii) DTI Consortium £3 M (Fibre process)BoeingHexcelThomas SwanInst. of Occupational Medicine

(iii) New Company “CUFLO” To bridge the University/industrial divide in UK

(iv) TinyTech KIC ?

The CMI Mission

To enhance the competitiveness, productivity and entrepreneurship of the UK economy…

By improving the effectiveness of knowledge exchange between university and industry, educating leaders, creating new ideas and developing programmes for change in universities, industry and government …

Using an enduring partnership of Cambridge and MIT, and an extended network of participants.

CMI: Defining a space for knowledge exchange across research, education and industry

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