laser induced die transfer and patterning
TRANSCRIPT
LASER INDUCED DIE TRANSFER AND PATTERNINGdr.ir. GERT-WILLEM RÖMER
Workshop "Microassembly: Robotics and Beyond" with IEEE International Conference on
Robotics and Automation ICRA 2013, May 10th, 2013, Karlsruhe, Germany
LASER INDUCED DIE TRANSFER AND PATTERNINGPRINCIPLE OF LASER MATERIAL PROCESSING
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Laser beam (emitted
by laser source)
LASER MATERIAL PROCESSING
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Lens
LASER MATERIAL PROCESSING
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Material
LASER MATERIAL PROCESSING
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Track
LASER MATERIAL PROCESSING
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Additional material
• gas
• wire
• paste
• powder
LASER MATERIAL PROCESSING
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Surface
LASER MATERIAL PROCESSING
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Processed material
LASER MATERIAL PROCESSING
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Absorbed laser energy can be used for, material
removal
modification
addition
LASER MATERIAL PROCESSINGPROCESSES
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Material removaldrilling, cutting
LASER MATERIAL PROCESSINGPROCESSES
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Material modificationwelding, marking, bending, transformation hardening
LASER MATERIAL PROCESSINGPROCESSES
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Additive processesSoldering, cladding, 3D printing (Selective Laser Sintering/Melting)
LASER MATERIAL PROCESSINGADVANTAGES
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Laser material processing is:
fast
accurate
flexible in terms of:
• the type of material to be processed and
• product geometry
small heat-affected-zone (HAZ)
contact-free tool
easy to automate
LASER MATERIAL PROCESSING
Two types of laser processes:
1. Pyrolytic processes:
thermal processing
typical processing dimensions 1 mm
2. Photolytic processes:
chemical processing (breaking chemical bonds)
typical processing dimensions 0.1 m
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Two examples/applications:
(both in the field of micro-assembly)
1. Laser induced Die transfer (pyrolytic)
2. Laser patterning for fluidic self-alignment (photolytic)
CONTENTS
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LASER INDUCED DIE TRANSFER
CONTENTS
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PYROLYTIC PROCESS
LASER INDUCED DIE TRANSFERPRINCIPLE
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TapeGlue
Micro part (Si)
Receiver
Laser Die Transfer is a technique to:
release a micro-component (e.g. Si 300300200m3)
from its carrier (tape), and
propel it towards a receiving substrate
LASER INDUCED DIE TRANSFERPRINCIPLE
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Laser
beam
Lens
LASER INDUCED DIE TRANSFERPRINCIPLE
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Absorption of
laser energy
LASER INDUCED DIE TRANSFERPRINCIPLE
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Part propulsion
LASER INDUCED DIE TRANSFERPRINCIPLE
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Part positioned on receiver
LASER INDUCED DIE TRANSFERTWO POSSIBLE APPROACHES
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Two possible approaches:
Absorbed laser energy is used for:
1. Heating of the interface of
(thermal sensitive) tape and
micro part
2. Explosive evaporation of the
interface of tape and micro part
LASER INDUCED DIE TRANSFERQUESTIONS
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Questions studied in this project were:
Which process (heating or evaporation) works best?
What are achievable accuracy and speed of die transfer?
Will the micro part (Si die) be thermally damaged?
LASER INDUCED DIE TRANSFEREVAPORATION INDUCED RELEASE EXPERIMENTS
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Laser source: Rofin Sinar RS.M-50D
Pulse duration: 45 ns
= 1064 nm (IR)
Top hat intensity profile
Focus diameter: 100 to 200 m
Parts:Si die 335335190 m3
Tape: Nitto STW “blue” tape
• 100 m PVC foil, with
• 50 m adhesive
LASER INDUCED DIE TRANSFEREVAPORATION INDUCED RELEASE EXPERIMENTS
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After release the die:
Rotates/tumbles
Velocity 4 to 6 m/s
Deviates ±4 deg. from vertical
Time between frames: 100 s
LASER INDUCED DIE TRANSFEREVAPORATION INDUCED RELEASE EXPERIMENTS
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Placement accuracy (of die on receiver):
x = hsin
were h = tape-to-receiver gap
With = ± 4º and h = 0.5mm x = 34.8 m < 35 m
LASER INDUCED DIE TRANSFERTHERMAL INDUCED RELEASE EXPERIMENTS
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Laser source: Unitek Miyachi ML-50A
Pulse duration: 0.2 ms
= 532 nm (Green)
Top hat intensity profile
Focus diameter: 540 m
Parts:335335190 m3
Tape: Revalpha tape
LASER INDUCED DIE TRANSFERTHERMAL INDUCED RELEASE EXPERIMENTS
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LASER INDUCED DIE TRANSFERTHERMAL INDUCED RELEASE EXPERIMENTS
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Less rotation/tumbling
Velocity 0.8 to 1 m/s
Deviates ±2 deg. from vertical
(= well within specs)
Time between frames:
• (a) & (b) 500 s
• (c) & (d) 400 s
LASER INDUCED DIE TRANSFERTHERMAL INDUCED RELEASE EXPERIMENTS
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Finite Element Model (FEM)
Temperature distribution
at moment of die
release (after 0.073 ms)
Tmax< 400 K < Tdamage
Tdamage= 673 K
Ep= 5.94 mJ
PHD THESIS
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http://dx.doi.org/10.3990/1.9789036532600
LASER PATTERNINGFOR FLUIDIC SELF-ALIGNMENT
CONTENTS
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PHOTOLYTIC PROCESS
LASER MATERIAL PROCESSING
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Photolytic processing = chemical processing,
i.e. photon-induced breaking of chemical bonds
Requires high photon intensity and/or
(ultra) short laser pulse
Laser pulse duration >1 ns thermal processing
Laser pulse duration < 1 ps cold processing
LASER MATERIAL PROCESSINGLONG PULSE PROCESSING
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LASER MATERIAL PROCESSING(ULTRA) SHORT PULSE PROCESSING
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LASER MATERIAL PROCESSING(ULTRA) SHORT PULSE PROCESSING
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B.N. Chichkov, C. Momma, S. Nolte, F. von Alvensleben, and A. T¨unnermann. Femtosecond,
picosecond and nanosecond laser ablation of solids. Appl. Phys. A, 63:109–115, 1996
LASER MATERIAL PROCESSING(ULTRA) SHORT PULSE PROCESSING
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Advantage: accurate processing
Disadvantage: low removal rate
10 m3 to 100 m3 per pulse
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Aligned
parts
Receptor
site
Liquid
droplet
Gripper
with part
Part on
dropletCapillary
forces aligns
part
(typ. 100100m2)
(after droplet
evaporates)
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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• Relies on accurate hydrophobic-hydrophilic pattern
(or wetting contrast) to pin droplet to receptor site
• Approach: use laser to create hydrophobic-
hydrophilic patterns (receptor sites).
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Factors determining wetting properties of a surface:
1. Chemical composition
2. Topography:
a. roughness or texture (area)
b. obstacles or edges (lines)
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Edge approach
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Edge approach
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Edge approach
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Substrate (lead frame)
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Experimental setup Laser source: Trumpf TruMicro
• Pulse duration: 6.7 ps
• = 1030 nm (IR)
• THG: = 343 nm (UV)
• Linear polarized
• Gaussian fluence profile
• M2<1.3
• Galvo-scanner
• Telecentric f -lens (100mm)
• Focus diameter: 15.6 m
• Clean room: class 4
• 20 ºC, Rel. Humm. 50%,
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Confocal Laser Scanning Microscope image
1 µJ, N=4
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Receptor sites
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Fluidic test setup
Part: SU-8 chip
Liquid: water
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Fluidic test setup
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Site: 200×200 µm2
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Site: 200×200 µm2
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Results
• Each receptor site was tested 11 times
• 100% successful alignment is <140º
• Accuracy:
• Position: 0.25±0.86 µm
• Angular: 0.35±1.22º
THANK YOU FOR YOUR ATTENTION
CONTENTS
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CONTACT
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FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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• Typical position accuracies: <1 m & <0.5 (for m2
parts)
• Typical initial positioning tolerance: 50% of part length
• When combined with pick-and-place robot fast and
accurate assembly process
LASER INDUCED DIE TRANSFEREVAPORATION INDUCED RELEASE EXPERIMENTS
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LASER INDUCED DIE TRANSFERTHERMAL INDUCED RELEASE EXPERIMENTS
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FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Chemical approach
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Roughness approach
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Edge approach
Gibbs’ inequality:
Y < < (180 – α) + Y
Y : Young’s contact angle Y
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Experimental setup
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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• Commercial leadframe with
roughened PrePlated Finish
(PPF)
• Surface roughness:
Ra1.5m
• Polyimide foil (polymer)
• Surface roughness:
Ra0.04m
Substrates
FLUIDIC DRIVEN SELF-ALIGNMENTFOR EFFICIENT AND PRECISE 3D POSITIONING OF MICROPARTS
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Experimental approach
• Machining of single trenches by applying pulses:
Overlapping pulses:
@ 400 mm/s & 400 kHz
implies: 94% pulse overlap
Parameters varied:
• Pulse energy: 0.25, 0.5 & 1 µJ
• Number of overscans : N=1 … 25