Multiphysics Modeling of Mechanically Flexible Materials

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ITG Forum Tues. October 5, 2004
Multiphysics Modeling of Mechanically Flexible
Materials with FEMLAB - Applications in
Plastic Electronics by Etienne Menard
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Finite Element Modeling with FEMLAB
FEMLAB has an extensive range of application
areas
Acoustics Structural mechanics Bioscience Transpo
rt phenomena Chemical reactions Porous media
flow Diffusion Quantum mechanics
Electromagnetics Semiconductor devices Fluid
dynamics Radio-frequency components Fuel
cells Photonics Geophysics Microwave
engineering Heat transfer Wave
propagation MEMS Optics with a true
multiphysics capability
  Acoustics  Convection-diffusion  Heat
transfer  AC and DC electromagnetics
 Electrostatics  Magnetostatics
 Incompressible fluid flow (Navier-Stokes
equations)  Structural mechanics  The
Helmholtz equation  The Schrödinger equation
 The wave equation
Draw system geometries
Define material/field properties boundaries
conditions
Create mesh
Solve problem
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Mechanical Influence of the back layerin
composite stamps
Exact solution
Hgtgta, Hgtgtw, hltlta
Contact
No Contact
1Constraints on Microcontact Printing Imposed by
Stamp Deformation, Langmuir 2002, 18, 1394-1407
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Sagging of the raised areas of PDMS stamps
P
Glass or PI PDMS
y displacements
y
x
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Confrontation of mechanical model to experimental
results
Test Pat6 2w 20.5µm
Test Pat1 2w 60µm
2w
Downward displacement
PDMS density ?950 kg/m3 Poisson ratio
?0.48 Youngs modulus E0.1MPa Stamp height
H10mm Features height h500nm P ?.g.H-93.2 N
(/m2) For 2a2w21µm Langmuir
FEMLAB 16.1 nm 16.4 nm
10mm thick PDMS stamp
10mm thick PDMS stamp
10mm thick PDMS stamp
Kapton based stamp
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Micro-discharge and electric breakdown in a
micro-gap
Air strength 3V/µm ?
Ono T. et al., J. Micromech. Microeng. 10 (2000)
445451.
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Air dielectric transistor
PDMS stamp
Master
2µm
Ti/Au coating
Single Crystal
D
S
G
manuscript accepted for publication in Adv. Mat.
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Finite Element Simulation of Fringes Fields
Metal coated glass slide
h
Air
W50µm
Infinite plate model
Fringes
55
45
PDMS ?r2.8
manuscript accepted for publication in Adv. Mat.
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Air dielectric characterization
h3.08µm
h3.77µm
h4.89µm
manuscript accepted for publication in Adv. Mat.
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Electrostatic forces
PDMS E 3MPa ? 0.48
Vertical displacement
V 50V on 1µm gap ? Femax 84.9 kN/m²
manuscript accepted for publication in Adv. Mat.
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Electrostatic forces
Ti/Au coated glass slide
h
Fe
PDMS
manuscript accepted for publication in Adv. Mat.