ROTATING THIN FILM DISK SLIDER / HEAD X - (CF 2 O) y (CF 2 CF 2 O) z CF 2 - X CH 2 OH (functional group) perfluoromethylene oxide groups (C1) perfluoroethylene oxide groups (C2) polar group polar group backbone • Confined film undergo “glass transitions” at a temperatures well above the bulk T g (56 vs. -115 °C). • Kinetics is dependent on the relative flexibility of the PFPE backbone. • Changes occur in time Monolayer Lubrication of Hard Drives NanoScience & Lubrication NanoScience & Lubrication 1 10 40 Si Cr CHx Zdol [nm ]
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ROTATING THIN FILM DISK SLIDER / HEAD X - (CF 2 O) y (CF 2 CF 2 O) z CF 2 - X X CH 2 OH (functional group) y perfluoromethylene oxide groups (C1) z perfluoroethylene.
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ROTATING THIN FILM DISK
SLIDER / HEAD
X - (CF2O)y (CF2CF2O)z CF2 - X
X CH2OH (functional group) y perfluoromethylene oxide groups (C1)z perfluoroethylene oxide groups (C2)
polargroup
polargroupbackbone
• Confined film undergo “glass transitions” at a temperatures well above the bulk Tg (56 vs. -115 °C).
• Kinetics is dependent on the relative flexibility of the PFPE backbone.
• Changes occur in time dependence as well as bonding rate constant.
Fractal Bonding in Hard-Drive LubricationNanoScience & LubricationNanoScience & Lubrication
HOLES / BITS
SUBSTRATEPOLYMER
Thermomechanical storage in thin polymer films demands unique flow and retaining properties of polymers.
NanoScience & Information StorageNanoScience & Information Storage
Quest for Higher Density Storage Media
Widely expected for Magnetic Storage Devices: Superparamagnetic Limit of 100 Gb/in.2
SUBSTRATEPOLYMER
SUBSTRATEPOLYMER
Q
CANTILEVER TYPE READ / WRITE
PROBE
Q
Heat Cantilever Resistively
Q
A possible alternative to magnetic recording: Thermomechanical Ultrahigh Density Storage in PolymersExpected recording density: 1 Tb/cm2 (1000 Gb/cm2)
NanoScience & Information StorageNanoScience & Information Storage
Millipede Storage Concept
2 mm 200 m 20 m 2 m
A 2D ARRAY OF LOCAL PROBES IS OPERATED IN A PARALLEL / MULTIPLEX FASHION.
Cantilever Array: (7 14 mm2)
32 32 (1024) Cantilevers
Vettiger, et al., IEEE Transactions on Nanotechnology, 1 (2002)
NanoScience & Information StorageNanoScience & Information Storage
Millipede – A Heat Transfer Challenge
Holes show undesired
- Rim Formations
For instance:
Concerns are
- local thermal transport,
- dewetting instabilities and hole retention,
- and timed backflow (bit erasing).
Fundamental Challenge:The scaling behavior of thermoplastic and thermoset polymers is simply not well-established, neither in fundamental understanding nor in performance.
Vettiger, et al., IEEE Transactions on Nanotechnology, 1 (2002)
Nano-Remediation and Energy Conservation
Significance: Environment and Energy Conservation
• Sieves/Membranes: Novel approaches for single pore separation systems.• Proton Exchange Membrane (PEM): Shift from
Combustion to Chemical Reaction for Energy Generation.
Nano-Remediation and Energy Conservation
Proton Exchange Membrane (PEM) Fuel Cell
PEM
50-175m5-50m
ACTIVE LAYER
ANODE CATHODE
4H++4e-+O22H2OH+H22H+ + 2e-
NafionNafion consists of a hydrophobic tetrafluoroethylene (TFE) backbone with pendant side chains of perfluorinated vinylethers terminated by ion-exchange groups.
Nano-Remediation and Energy Conservation
60 70 80 90 100 110 120 130 1400.048
0.050
0.052
0.054
0.056
0.058
0.060
0.062
0.064
0.066T
c=79 oC T
g=116 oC
Am
plitu
de R
espo
nse
(A. U
.)
Temperature (oC)
Control of Transport Properties from a Nanoscopic Interfacial Perspective
Topography Elastic Response Map
Working principle illustrated on N2 diffusive flux through a Ceramic Zeolite Membrane, measured in-situwith surface morphology.