Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Laser based micro fabrication systems for
electronics packaging
Dr. Haibin ZhangDirector Technology Development, Electro Scientific Industries, Inc., 9/8/2016
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Adv. Packaging: new processes, new materials, new challenges
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Challenges for Semiconductor Manufacturers
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Chasing Moore’s Law: Requires increased transistor density, cost scaling, and
performance per watt.
Processing Challenges:
• Shrinking Node Sizes
• Low K Materials
• Thin Materials
• Wafer Coatings
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Laser applications in semiconductor and electronics packaging
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Micro-via
Drilling
Marking
Ablation
Dicing/Scribing
Substrate
dielectricPCB
dielectric
Patterning
Wafer mark
TSV TMV Flex via
Hard mark Soft mark
Thin wafer Wafer + DAF Dielectric scribing
Package mark
Laser direct patterning Memory repair link blowing
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Laser mark
Higher density demand smaller features and higher accuracy
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1um 10 um 50 um 100 um 1000 um
1um
10 um
50 um
100 um
Feature size (um)
Accuracy
TSV
Link
blowing
LDI/LDA
Scribing/dicing
Routing / skiving
Substrate/PCBVIA,
TMV
*Estimates
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Higher density,
lower cost
Resolution
Accuracy
Quality
Cost
<1um link
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Route to high density, high accuracy, and low cost
<10 um via <30 um scribe
• Mechanical structure
• System Architecture
• Beam steering
• Optical design
• Calibration
• Match laser to the application
• Smart beam delivery and control
• Understand the physics
• Select platform most fit the
application
• High speed beam delivery and
high laser power to offset high
cost components
• Improved yield provide value
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
AccuracyStability, repeatability, error budgeting, measurement, and calibration
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45 µm
Stage
DiagnosticsDebris Management
Calibration Metrology
Beam Steering
Power Control
Focus Control
Realtime Control
0 5 10 15 20 25-5
0
5
Po
sit
ion
(m
m)
0 5 10 15 20 25-6
-4
-2
0
2
4
6
msec
Err
or
(um
)
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1
-0.5
0
0.5
1
9970 Alpha, KT2
Relative Displacement (WrkSurf - BeamSpot)
Xinput -> SingleStep, 10Hz Sine, 67kg*1.3g
[sec]
[um
]
X
Y
Z
AccuracyModeling. Example: ESI Kinematic Transform Tool (KT2)
Beam Path in KT2
Modal Analysis
Beam Deflection
Prediction
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
AccuracyRange of components provide variety of repeatability. Example: stages
Cost
Repeatability• Modal testing
• Custom chucks
• Isolation design
• Interferometry
Air Bearing
Planar XY Mechanical
10 µm
1 µm
0.1 µm
Cross-Axis Mechanical
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
AccuracyRadial accuracy data achieved, multi-head
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Radial Error
|M| + 4σ < 6 um
Example: ESI Cornerstone micro-via drilling platform
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
QualityPick the right laser for the application
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
QualityThe right absorption and pulse width
Tailor laser wavelength with respect
to material stack and properties
Select the proper pulse width laser
for quality and speed
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
TMV, CO2 laser Flex, ns UV
Thin wafer, fs green Substrate dielectric, ps UV
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QualityRight laser for the application
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
• Range of Z-stage solutions:
– Stepper-driven roller bearing
– Linear motor cross-roller bearing
– Linear motor air bearing
• Z surface mapping with typical metrology
– Visual focus
– Laser triangulation
– Beam to work control
• Realtime tracking
– Sub-micron to 10’s of microns
QualityFocus Control enables feature consistency resulting high yield
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
QualityUnderstanding process shortens development time, improves quality, and lowers cost
Knowledge base
ExperimentsMetrology
Spec requirement
Process
Development
copper
polymer
glass fiber
2
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copper
polymer
glass fiber
cross-section view
cross-section view
Example: FR4 via drilling with CO2 laser
Physics:
Simulation
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Lower cost Reduce component cost and improve output
𝐶𝑜𝑠𝑡 𝑝𝑒𝑟 𝑓𝑒𝑎𝑡𝑢𝑟𝑒 =𝑜𝑣𝑒𝑟𝑎𝑙𝑙 𝑐𝑜𝑠𝑡
𝑇ℎ𝑟𝑜𝑢𝑔ℎ𝑝𝑢𝑡
Overall Cost
System cost
Laser Reduce cost per photon
Optics OTS components
Control Fast and efficient
Frame Accuracy and cost
ProductionOperation Low interruption
Yield Process stable
Maintenance Low MTTR
Service/repair Fast response high reliability
Throughput Parallel processing Multiple heads
Speed of pulses (reprate)
Use of high repetition rate lasers
Wait/move time Fast scanning mechanisms
Material response Thermal relaxation Enough time to dissipate heat
Plume/plasma Larger pulse spacing
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Fiber
DPSS
Disk
Slab
1 MHz
2 MHz
0.8 MHz
2 MHz1 MHz
High power femtosecond lasers Higher laser
average power
Reduced per
photon cost
Lower cost of
manufacturing
Increased speed
High pulse rate
introduce heat
Low pulse overlap allow
heat to dissipate
Extreme fast steering
reduces pulse overlap
Good quality features
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Lower costHigher power laser and fast steering enable higher output at lower photon cost
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Lower costBeam steering components offer high speed scanning with scan range tradeoff
Range
Bandwidth
Acousto Optic
Deflector
Piezo Fast Steering
Mirror
Galvo
1 MHz
1 kHz
100 Hz
100 µm 1 mm 10 mm
Stage
100 mm
10 kHz
100 kHz
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Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
Lower costCompound beam positioning provide ultimate efficiency: speed + range
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535mm
20mm
20
mm
~0.15mm
~0.1
5m
m
63
3m
m
Example: ESI tertiary beam positioning
system (Third Dynamic®)
Linear Stages provide the overall range of
motion for the target panel dimension
Galvos provide fast intra-via beam positioning
AODs provide ultra-fast beam positioning for
rapid and precise tooling actions
Galvo Movement AOD Movement
= + +
Ultra-fastFastSlow
Beam Position Linear Stage Movement
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
The right laser tools for adv. packaging
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The right platform
The best laser for the application
Smart control for performance
Rigorous design for customer value
High accuracy
Small feature
Dense pattern
Superior value
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
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Processes, Technologies, Techniques and Materials
Display
Cutting, marking,
patterning of brittle
materials
Flex Circuits
Highest throughput in
via drilling and routing
Advanced
Interconnect
PCB Drilling, cutting
and routing
Stacked Die
Scribing and dicing of
wafers
Enclosure
Marking, drilling,
cutting, inspection
Circuit Trim
Wafer, circuit and
component trim
PCB
Semiconductor
Micromachining
Component
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
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Laser based fabrication tools in electronics packaging transfers
value to the end customer
• Functionality
• Reliability
• Build Quality
• Form Factor
• Affordability
Mobile Devices
Internet of Things
End Markets
Electro Scientific Industries, Inc. – SEMICON Taiwan 2016
ESI at a Glance
• Founded 1944
• Technology: Laser-based
microfabrication
• Valuable intellectual property portfolio
• Markets: Consumer Electronics,
Semiconductor, Industrial
Micromachining
• Manufacturing: Singapore, United
States, China
• Employees: ~700
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