MECH152-06 -L2- 1
Engineering Specification &
Design Portfolio
MECH152-06 -L2- 2
Engineering Design
System Design
Detail Design
Start Here!
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Design Process• Define Functional Needs• Functional Specification (Continuous updating)• Engineering Specification (Continuous updating)• Detail Design
– Design for Manufacturing– Design for Assembly and Disassembly– Life Cycle Design
• Prototyping• Production• Product Launch • Maintenance and Support• Product Recycling
Concurrent and Iterative Activities
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Design Procedure
Functional NeedsFunctional Specification
Design Analysis
Engineering Specification
Detail DesignLife Cycle Design
Design for Assembly and DisassemblyDesign for Manufacturing
Subsystem Decomposition
ManufacturingProcess
Plan
Maintenance
Recycling
Product
Marketing
Matl. Selection
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Design Specification• Functional Specification
– Overall requirements– Key functionalities– Overall dimensions– Key performance characteristics– Layout drawing
• Engineering Specification– Detail performance requirements– Subsystems and subsystems detail requirements– All relevant dimensions – Engineering drawings
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Design Portfolio• Design specification - Contract• Design Schedule• Functional design
– Design alternatives– Design evaluation
• Final design solution– Design model and analysis– Engineering drawings– Process Plan
• References• Meeting notes
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System Design
• Define Functional Needs
• Functional Specification (Continuous updating)– Review existing information
• Existing designs, patents, codes, legislation, literature search
– Decomposition into subsystems• Overall layout
• Subsystem relationship
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Flip Chip Bonder
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Functional Specification Development
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Process Flow IStep 1a - Pattern developed on bare silicon
template
1. Clean silicon substrate by sulfuric acid & hydrogen peroxide at 120°C for 10mins
2. Rinse with deionized water and dry clean
3. Spin coat standard photoresist
4. Conduct photolithography by UV exposure
5. Wet etch the pattern by KOH (anisotropic etching)
6. Photoresist stripping
7. Rinse with deionized water and dry clean
8. Dicing
Silicon Template
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Process Flow II
Step 1b - Soft mould Preparation
1. Apply mould release (silicone) on silicon template
2. Clean another silicon substrate by sulfuric acid & hydrogen peroxide at 120°C for 10mins
3. Rinse with deionized water and dry clean
4. Spin coat polymer (PMMA / PDMS)
Silicon Template
Silicon TemplatePolymer
Pressure
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Process Flow IIIStep 1c - Pattern transfer to the
soft mould– Apply silicon template onto
polymer with pressure (<5bars)
– Curing polymer with suitable conditions
– Release of silicon template
• Step 1d - Soft mould fabricated
Heat
Heat
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Process Flow IV
Step 2 - Dipping of soft mould on conductive polymer
1. Apply a layer of conductive polymer into the paste pot
2. Turning the pot and set the height of the paste by height adjustable blade
3. Dipping of soft mould on the conductive polymer
Silicon substrate
Conductive Polymer
PDMS / PMMA Mould
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Process Flow V
Step 3 - Die preparation
1. Dicing
2. Load into magazine
Wafer Magazine
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Process Flow VI
Step 4 - Formation of interconnect
1. Alignment is conducted between soft mould and IC die
2. Apply soft mould onto the die (displacement control)
3. Lifting of the soft mould for next cycle
4. Soft mould will undergo Step 2 for next die
IC die
Pressure
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Process Flow VII
Step 5 - Assembly process
1. Bumped chip is flipped
2. Alignment is conducted between bumped IC die and substrate
3. Apply bumped IC die onto the substrate (displacement control)
Sub-mount / substrate
Bumped Chip
IC die
Pressure
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Process Flow VIII
Step 6 – Curing
1. Batch if assembled package is collected
2. Batch curing of conductive polymer in conventional oven
3. Underfilling is optional
Underfill IC die
Heat
Heat
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Functional Specification I
• Target Package
• Base Table
Pad size 20μm - 100μm
Pitch (Min) 20μm
Chip size 0.4mm x 0.4mm – 10mm x 10mm
Size 40mm x 40mm x 0.5mm
Material handling Class epoxy, ceramic, glass, flim
Alignment accuracy X±2μm, 3σY±2μm, 3σθ±0.01˚ 3σ
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Functional Specification II• Bonding Head
• Camera Table
Bonding pressure <5barHead bonding temperature (max) 400˚C, +30˚C
Temperature accuracy ±1deg
Cooling system Air coolingLoading time Max. 200sec, resolution 0.1sec
Stage Movement 0.5μm per stepLeveling resolution -
Image processing device Gray scale pattern matchingFocusing system
Table movement (x-y motion) 1μm per step2 camera Two side camera
Chip: 0.4-0.6mmSubstrate:1-2mm
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Engineering Specification Development
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Polymer Flip Chip Bonder - Schematic
Camera 1 - WaferCamera 2 - FlipCamera 3 - Substrate
Dipping Bath
Epoxy Pot System Die Pick-up Arm
Wafer System
Substrate Work Holder
Vacuum
Optics 1
Optics 2
Optics 3
Ө X Y Z
Polymer Flip Chip Bonder Schematics
Flipping System
Stamping Arm System
Ejector System
DieOrient-Ө
Flip-ӨFlip-Ө
Flipping SystemSubstrate Work
Holder
Z
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Polymer Flip Chip Bonder
MECH152-06 -L2- 23Polymer Flip Chip Bonder Specification - I
Machine Structure ModuleEpoxy Pot Systemfor Conductive Polymer
Adjustable Epoxy Blade height by Micro-gauge-Feed at 0.5mm/rev.
Dipping for cleaning the Stamping Head
Stainless Steel Container with Ultrasonic cleaning-Frequency >40kHz
Vacuum Systemfor drying up the Stamping Head after cleaning
With filter
Substrate Work Holder - X-travel 100mm, resolution 2.5um/step
- Y-travel 200mm, resolution 2.5um/step
- Z-travel 5mmChassis & Frame Cast Iron & Marble Stone, Casters
with Adjustment Pad
MECH152-06 -L2- 24Polymer Flip Chip Bonder Specification - II
Machine Control ModuleController - Motion control: Pentium 4 grade controller system
- Vision PR: Pentium 4 grade controller systemVision Alignment System
3 set 256-grey scale 1/3” CCD (at Wafer/Flip/Substrate)Adjustable magnification (0.7X – 4.5X)640x480 pixels resolution (2-11 um/pixel)Coaxial and Ring light illuminationPCI Video Capture card (PAL, 30 frames/sec)Manual adjustment and focusing range-X-travel 10mm-Y-travel 10mm-Z-travel 10mm
Motion Control System Digital Signal Processing (DSP) control for-Ejector System (X, Y, EjectorCap-Z, EjectorPin-Z)-Wafer System (X, Y)-Substrate Work Holder (X, Y, Z)-Flipping System (X, Y, DieOrient-Ө, Flip-Ө)-Die Pick-up Arm (Z, Ө)-Stamping Arm System (X, Y, Z)
Air Source Vacuum 0.8mmHg / Compressed Air 0.1-0.2 barDAC Controller 8-bit resolutionADC Controller 0-5V DCTemperature Controller
400ºC (max) / +30ºC ramp /10ºC accuracy
MECH152-06 -L2- 25Polymer Flip Chip Bonder Specification - III
Wafer Handling ModuleTarget Packages LED, COG, COF
Wafer System - X-travel 150mm, resolution 5um/step- Y-travel 150mm, resolution 5um/step
Ejector System - X-travel ±10mm, resolution 1.5um/step- Y-travel ±10mm, resolution 1.5um/step- EjectorCapZ-travel 24mm, 4um/step- EjectorPinZ-travel 24mm, 4um/step
Wafer Handling - 6” Wafer with 8” Ring- Conversion Kit for 2” Waffle Pack
Missing die detector
Photo sensor
MECH152-06 -L2- 26Polymer Flip Chip Bonder Specification - IV
Pick, Dip, Flip ModuleVacuum holder 1.0 mmHg
Force Control Sensor 3 set (Pick/Stamp/Flip)Range 0-150gDAC control
Die Pick-up Arm - Z-travel 5mm- Ө -travel 180º, 0.45º/step
Stamping Arm System
- X-travel 200mm, resolution 5um/step- Y-travel 200mm, resolution 5um/step- Z-travel 100mm
Flipping System - X-travel 10mm, resolution 1.25um/step- Y-travel 10mm, resolution 1.25um/step- Flip-Ө -travel 180º, 0.45º/step- DieOrient-Ө-travel ±180º, 0.45º/step
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System Design
Sub-system I
Sub-system II
Sub-system III
Relationship A Relationship C
Relationship B
Relationship D
Overall
System
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System Design
• Internet
• Patent database – http://www.ttc.ust.hk http://www.ttc.ust.hk
• IP and Patent Search Links (WIPS)– e.g. printer head + Epson
• Research database– http://ustlib.ust.hk http://ustlib.ust.hk
• Database List – (SCOPUS)– Printer head (title) + Epson (Affiliation)
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Design Evaluation MatrixFunction
(Functions in the Functional Specification)
Weighting
(Weighting showing the importance of the
function)
Score
Alternative 1
Alternative 2
Alternative 3
Function 1 W1 R11 R12 R13
Function 2 W2 R21 R22 R23
Function 3 W3 R31 R32 R33
Function 4 W4 R41 R42 R43
Total score R11*W1+R21*W2+ R31*W3+ R41*W4
R12*W1+R22*W2+ R32*W3+ R42*W4
R13*W1+R23*W2+ R33*W3+ R43*W4