Using Tape

1
Using Tape Reel for High Volume Flip Chip
Delivery A Manufacturing Analysis
Presented at MCC/EIA/SEMATECH KGD Industry
Workshop September 19, 1997

• Joint Study by
• Pat Jones - Delco Electronics Corporation
• Lisa Bernal Brethour - Surface Mount Taping, Inc.
• Tom Becker - 3M

2
Presentation Outline

• Background
• Test Plan
• Test Procedure
• Material Selection
• Wafer to Tape and Reel Results
• Transportation Test Results
• Bump Shape Analysis
• Spectral Analysis
• Pick and Place Test Results
• Conclusions and Recommendations

3
Statement of Need

• Need for low cost /high volume packaging
• Need to use existing SMT assembly equipment and
  tooling
• Need to use standardized embossed packaging media
• Need for documented research
• Need for industry standard for high volume flip
  chip packaging

4
Objective

• Determine feasibility of using standard embossed
  tape and reel packaging for flip chip ICs bumps
  down
• Determine functional range of sizes of flip
  chips in standard pockets
• Provide design model for sizing embossed pockets
  to flip chips
• Provide research to the semiconductor industry to
  assist in standardization

5
Experimental Scope

• Use a range of flip chip sizes
• Use a common flip chip thickness
• Develop experimental factorial design for chip
  size vs. pocket size
• Use common eutectic bumps with similar metallurgy
• Use of standardized FSTM shipping test method
• Use of standardized component handling equipment

6
Joint Division of Responsibilities
7
Process Flow
8
Flip Chip Description
Bump Metallurgy Eutectic Sn/Pb 60/40 or 63/37
9
Flip Chip Photos
MSFB,4-UP
MSFB
FDIZ
8 mm Tape
Photos to scale
MFDS
24 mm Tape
12 16 mm Tape
10
Embossed Carrier Description

• 3M Conductive Polycarbonate Carrier 3000BD
• 3M Conductive PSA Cover Tape 2666
• Precision Flat-bottom Pockets
• All pockets (except TC10) are worst-case for
  bump contact with carrier
• Bevel Edge with Raised Cross-bar pocket design

Bare Die

11
Bevel Edge Pocket Design
Low Draft Angles for better containment! (lt 5.0
degrees)
Bevel-edge pocket design for ease of use in
loading!
Precision Flat-Bottom Pocket (/- 0.002)
Actual Cross-Section of 3M CSP Carrier Tape
12
Pocket Sizing Factorial
13
Wafer-to-Tape Process

• 100 visual inspection performed prior to pick
  manually inked damaged chips
• Bumps inspected to Delco Electronics Workmanship
  Standards
• Manually placed control dice in Gel-Pak, bumps
  up
• Generated vibration samples versus control in
  tape and reel

Gel-Pak is a product of Vichem Corporation
14
Wafer-to-Tape Equipment
15
Wafer-to-Tape

• Saw street variation from wafer-to-wafer affected
  system alignment
• Initial tape designs were difficult to seal,
  re-designed tape to resolve problem
• Vacuum tip needed re-design to pick up bumped die
  reliably

16
Wafer-to-Tape Results
17
Packaging and Shipping Method

• Partially filled 13 reels
• Anti-static bags
• Placed in primary shipping container (pizza box)
  with anti-static bubble wrap
• Placed in secondary shipping container with
  anti-static bubble wrap
• Shipped UPS Red
• - Tempe, AZ to Kokomo, IN

18
Delco Electronics Test Flow
Inspect 40 Die for Bump Damage Measure 10 Die
for Flatness Photograph typical and atypical
damage Spectral Analysis 5 die
Tape Sample 1A 50 die - Control
Inspect carrier pockets
Tape Sample 1B 450 Die - Test
Shipping Test
Pick Place 400 die
Collect rotation data Collect mis-pick data
Gel-Pak control samples
Reflow of Die Cold Joint Analysis
Reflow of Die Cold Joint Analysis
19
Shipping Test

• Federal Standard Test Method 101C
• Vibration Method 5019.1
• Vibrate on 3 sides - one hour each
• 0.5 unrestrained vertical movement
• Drop Test Method 5007.1
• Level B, procedures b, c and f
• 27 drop height

20
FDIZ Bump Photos
Control Gel-Pak
Control Tape Reel
Test Sample
SEM Photos
21
MSFB Bump Photos
Control Gel-Pak
Control Tape Reel
Test Sample
SEM Photos
22
MSFB4UP Bump Photos
Control Gel-Pak
Control Tape Reel
Test Sample
SEM Photos
23
FB250 Bump Photos
Control Gel-Pak
Control Tape Reel
Test Sample
SEM Photos
24
Bump Height Statistical Analysis

• Using computerized optical measuring system
• Repeatable to 2.5 um
• Analysis of mid-size FB250 bumps
• Analyzed bump heights and flatness
• Average and sigma

25
Bump Heights - Average
26
Bump Heights - Sigma
27
Bump Spectral Analysis
Uncontaminated
Contaminated
Out of 50 flip chips analyzed with 48 bumps each
(2, 400 bumps), only this small particulate of
contamination was detected during spectral
analysis.
28
Substrate Assembly Process

• SMD equipment with standard feeders (blind pick!)
• Data collection
• Rotation of flip chips in pockets
• Mis-pick information
• Reflow on test PCBs
• Comparison of modules with control vs. tested
  flip chips

29
Pick and Place Test Results
PP 1 vacuum chuck was not optimized for small
die and had difficulty picking up the FDIZ
components. PP 2 vision system was not
optimized for large components and had difficulty
seeing the large components.
30
Conclusions and Recommendations

• Use of standardized embossed tape reel solves
  high volume/low cost transportation needs
• Must limit die movement to lt 10 degrees to
  prevent die damage
• Carrier should be cleaned prior to use
• Existing SMT placement equipment is capable of
  blind picking flip chips from carrier tapes

31
Important Notice
3M is a trademark of 3M Company.
Important Notice Before using this product, you
must evaluate it and determine if it is suitable
for your intended application. You assume all
risks and liability associated with such use.
Warranty Limited Remedy Limited Liability 3Ms
product warranty is stated in its Product
Literature available upon request. 3M MAKES NO
OTHER WARRANTIES INCLUDING, BUT NOT LIMITED TO,
ANY IMPLIED WARRANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE. If this
product is defective within the warranty period
stated above, your exclusive remedy shall be, at
3Ms option, to replace or repair the 3M product
or refund the purchase price of the 3M product.
Except where prohibited by law, 3M will not be
liable for any loss or damage arising from this
3M product, whether direct, indirect, special,
incidental or consequential regardless of the
legal theory asserted.