WHISKER TEST REPORT

Whisker Test Report # : 20060623
Rev.00
WHISKER TEST REPORT
(FINAL REPORT)
General Information
Factory
Plating Finish
Package Type
Plating Chemistry
Plating Line
Post Plating Bake
Report Date
Whisker Test Report #
Amkor Technology Philippines – ATP
Matte Sn
SOIC
ST380
Meco 6
150°C for 1 hour
:
:
January 15, 2007
20060623
Prepared by
:
Sonny M. Copon
Reliability Engineer
Checked by
:
Roque Baliwan
Section Manager, Rel/FA
Approved by
:
Bernard Baylon
Department Manager, Rel/FA
Distribution List :
Bryan Rigg, Henry Carteciano, Greg Gabriel, Sandra Gonzales, Ruth Jacob, Charlie dela
Cruz Jr., Eduardo Mertola, Leonida Dapula, Rodrigo Amor, Avelette Tan – ATP
GiSong Lee, KwangBok Yang – WW Corp. PIC
Gary Hamming – ATI
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DISCLAIMER. The whisker test procedures identified in this report are used for determining
the presence of tin whiskers and are performed by Amkor, pursuant to current industryaccepted JEDEC standards. The whisker test procedures used herein are unproven and
may produce inconclusive results. Amkor makes no representation, warranty or guarantee
of any kind with respect to the field performance, quality or freedom from whisker-related
failures, of any package tested by Amkor using these procedures.
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1. Purpose
1.1. Whisker Test on SOIC 8lds (C194 Base Metal) ST380 Chemistry.
2. Scope: Mark (9) the scope on the following
Process
New plating process
Modified plating process
9
Material
New plating material
Modified plating material
Alternate source of material
Alternate manufacturing site of
material
3. Conclusion
3.1. Total # of lots tested : ( 3 ) lot(s)
3.2. Comment :
3.2.1. Whisker length measurement method applied for all the whiskers observed was the
Radial measurement method. Eighteen (18) terminations per readpoint were SEM
inspected and 2 longest whiskers per lot per readpoint were measured and reported.
Identified whiskers vary from one readpoint to another since the test objective was to
track the longest whisker growth among the samples.
3.2.2. Post 500cyc, 1000cyc, & 1500cyc exposure at –55°C/+85°C TC conditions showed
whisker growth in all 3 lots. Longest whiskers observed post 1500cyc were:
− TC without precon: comp#1, term#5 with 31.18µm;
− TC with 215°C simulated reflow: comp#5, term#3 with 38.40µm; and
− TC with 255°C simulated reflow: comp#6, term#3 with 27.08µm.
3.2.3. No whisker was observed in all 3 lots after 4000hrs exposure both at 30°C/60%RH
and 55°C/85%RH TH conditions.
3.2.4. Two (2) terminations with whisker, which were found at the lead tip, have been
invalidated after exposure to higher Temperature/Humidity (55°C/85%RH) conditions
due to presence of surface corrosion. The invalidation was done per JEDEC
Standard JESD201. Other terminations were inspected but no whisker was found.
Verification results were detailed at the end of report under Appendix 5.4.3.
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4. Package / Material Description
4.1. Package
Type
Body size
Lead Count
Lead Pitch
Lead to Lead Gap
SOIC
391x155 mils
8L
50 mils
N/A
4.2. Material
Lead frame
Base metal alloy
C194
Temper (1/2 hard, etc.) Full Hard
Stamped/Etched L/F
Etched
L/F thickness
8 mils
Barrier layer type
Pure Tin Over Copper
Barrier layer thickness
N/A
4.3. Process Dates
Plating date/time
Post bake date/time
Simulated reflow date
Board assembly date
30°C/60%RH start date
55°C/85%RH start date
-55°C/85°C start date
Lot #1
05/10/06 / 1115H
05/10/06 / 1135H
06/14/06
N/A
06/14/06
06/14/06
06/14/06
5. Attachments
5.1.
5.2.
5.3.
5.4.
Process Summary
Workmanship Summary
Whisker Test Summary and Photos
Appendix
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Lot #2
05/17/06 / 1425H
05/17/06 / 1440H
06/14/06
N/A
06/14/06
06/14/06
06/14/06
Lot #3
05/24/06 / 1630H
05/24/06 / 1655H
06/14/06
N/A
06/14/06
06/14/06
06/14/06
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5.1. Process Summary
Lot# : LOT-1
PROCESS
Plating
MACHINE/
EQUIPMENT
Meco 6
PARAMETERS
Belt Speed
Descale
• Temperature
• Concentration – Salt
• Concentration – Acid
Plating
• Current Density
• Ampere / cell
• Concentration – Acid
• Concentration – Tin
• Concentration – Pb
• Concentration – Bi
• Concentration – Additive
(Primary)
• Concentration – Additive
(Secondary)
• Bath Temperature
Impurities
• Carbon
• Pb in deposit
(for Matte Sn, Sn/Bi)
• Cu
• Fe
• Ni
• Sn+4
Post Plating Bake Yamato
8 m/min
Descale Solution
35°C
74.70 g/li
NA
168.70 ASF
220 amps/cell
272.50 ml/li
78.90 g/li
N/A
N/A
71.70 ml/li
3.00 ml/li
28°C
0.01225 % wt
3.90 ppm
2.69 ppm
8.77 ppm
14.23 ppm
1.56%
Hold Temperature
150°C
Dwell Time
Total Cycle Time
1 hr
1.5 hr
Simulated Reflow Vitronics
@ 215°C
Peak Temperature
Dwell Time > 183°C
219°C
63 seconds
Simulated Reflow Vitronics
@ 255°C
Peak Temperature
Dwell Time > 217°C
259°C
74 seconds
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MATERIALS
Actronal 988
Whisker Test Report # : 20060623
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WHISKER TEST REPORT
(FINAL REPORT)
Lot# : LOT-2
PROCESS
Plating
MACHINE/
EQUIPMENT
Meco 6
PARAMETERS
Belt Speed
Descale
• Temperature
• Concentration – Salt
• Concentration – Acid
Plating
• Current Density
• Ampere / cell
• Concentration – Acid
• Concentration – Tin
• Concentration – Pb
• Concentration – Bi
• Concentration – Additive
(Primary)
• Concentration – Additive
(Secondary)
• Bath Temperature
Impurities
• Carbon
• Pb in deposit
(for Matte Sn, Sn/Bi)
• Cu
• Fe
• Ni
• Sn+4
Post Plating Bake Yamato
8 m/min
Descale Solution
35°C
77.50 g/li
NA
168.70 ASF
220 amps/cell
270.50 ml/li
74.00 g/li
N/A
N/A
79.90 ml/li
3.30 ml/li
28°C
0.01225 % wt
3.73 ppm
6.84 ppm
19.81 ppm
5.65 ppm
1.56%
Hold Temperature
150 ºC
Dwell Time
Total Cycle Time
1 hr
1.5 hr
Simulated Reflow Vitronics
@ 215°C
Peak Temperature
Dwell Time > 183°C
219°C
63 seconds
Simulated Reflow Vitronics
@ 255°C
Peak Temperature
Dwell Time > 217°C
259°C
74 seconds
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MATERIALS
Actronal 988
Whisker Test Report # : 20060623
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(FINAL REPORT)
Lot# : LOT-3
PROCESS
Plating
MACHINE/
EQUIPMENT
Meco 6
PARAMETERS
Belt Speed
Descale
• Temperature
• Concentration – Salt
• Concentration – Acid
Plating
• Current Density
• Ampere / cell
• Concentration – Acid
• Concentration – Tin
• Concentration – Pb
• Concentration – Bi
• Concentration – Additive
(Primary)
• Concentration – Additive
(Secondary)
• Bath Temperature
Impurities
• Carbon
• Pb in deposit
(for Matte Sn, Sn/Bi)
• Cu
• Fe
• Ni
• Sn+4
Post Plating Bake Yamato
8 m/min
Descale Solution
35°C
80.70 g/li
NA
168.70 ASF
220 amps/cell
272.50 ml/li
80.40 g/li
N/A
N/A
78.00 ml/li
3.10 ml/li
28°C
0.01225 % wt
4.91 ppm
6.84 ppm
19.81 ppm
5.65 ppm
2.84%
Hold Temperature
150 ºC
Dwell Time
Total Cycle Time
1 hr
1.5 hr
Simulated Reflow Vitronics
@ 215°C
Peak Temperature
Dwell Time > 183°C
219°C
63 seconds
Simulated Reflow Vitronics
@ 255°C
Peak Temperature
Dwell Time > 217°C
259°C
74 seconds
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MATERIALS
Actronal 988
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5.2. Plating Workmanship Summary
Lot# : LOT-1
Process
/ SPEC No.
001-0530-2011
001-0522-2571
Test Item
Visual
Plating thickness
001-0522-2571
Deposit composition
Surface of Deposit Grain size range
MAX
Test Data
MIN
AVG
0/116
0/5 rdgs
N/A
578.60
N/A
512.40
N/A
549.10
PASSED
PASSED
N/A
N/A
N/A
2.86
N/A
2.04
N/A
2.41
100% Sn
# Failure /
S. Size
MAX
Test Data
MIN
AVG
001-0322-2595
400 – 700µ”
(10 – 17.50µm)
100% Sn
N/A
0/116
0/5 rdgs
N/A
575.80
N/A
515.80
N/A
548.50
PASSED
PASSED
N/A
N/A
N/A
1.95
N/A
1.80
N/A
1.89
100% Sn
SPEC # or
Criteria
# Failure /
S. Size
MAX
Test Data
MIN
AVG
001-0322-2595
400 – 700µ”
(10 – 17.50µm)
100% Sn
N/A
0/116
0/5 rdgs
N/A
572.40
N/A
508.70
N/A
549.10
PASSED
PASSED
N/A
N/A
N/A
1.92
N/A
1.72
N/A
1.82
100% Sn
SPEC # or
Criteria
# Failure /
S. Size
001-0322-2595
400 – 700µ”
(10 – 17.50µm)
100% Sn
N/A
SPEC # or
Criteria
Result
Lot# : LOT-2
Process
/ SPEC No.
001-0530-2011
001-0522-2571
Test Item
Visual
Plating thickness
001-0522-2571
Deposit composition
Surface of Deposit Grain size range
Lot# : LOT-3
Process
/ SPEC No.
001-0530-2011
001-0522-2571
Test Item
Visual
Plating thickness
001-0522-2571
Deposit composition
Surface of Deposit Grain size range
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Result
Result
Whisker Test Report # : 20060623
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WHISKER TEST REPORT
(FINAL REPORT)
5.3. Whisker Test Summary
5.3.1. Ambient Temperature/Humidity (30°C/60%RH)
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 3 / Term # 3 .
Comp # 4 / Term # 8 .
Comp # 2 / Term # 4 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3101 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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WHISKER TEST REPORT
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5.3.2. High Temperature/Humidity (55°C/85%RH)
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 3 / Term # 4 .
Comp # 4 / Term # 3 .
Comp # 2 / Term # 3 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3161 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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5.3.3. Thermal Cycling (-55/85°C)
Lot
Component # /
No.
Termination #
Lot-1 Comp # 1 / Term #
Comp # 6 / Term #
Comp # 6 / Term #
Lot-2 Comp # 1 / Term #
Comp # 2 / Term #
Lot-3 Comp # 5 / Term #
Comp # 6 / Term #
Comp # 4 / Term #
0 cyc
none
none
none
none
none
none
none
none
5.
8.
7.
3.
7.
4.
5.
1.
Readpoints
500 cyc
1000 cyc
16.79µm
23.20µm
22.41µm
22.46µm
17.16µm
21.23µm
14.30µm
17.65µm
17.15µm
20.98µm
15.05µm
22.60µm
-
1500 cyc
31.18µm
26.12µm
23.29µm
20.20µm
24.14µm
28.53µm
SEM Photo @ Post 500 cyc
SEM Photo @ Post 1000 cyc
Longest whisker growth of 22.41µm
Longest whisker growth of 23.20µm
SEM Photo @ Post 1500 cyc
Longest whisker growth of 31.18µm
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5.3.4. Ambient Temperature/Humidity (30°C/60%RH) post 215°C simulated reflow
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 4 / Term # 2 .
Comp # 2 / Term # 5 .
Comp # 3 / Term # 2 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3101 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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5.3.5. Ambient Temperature/Humidity (30°C/60%RH) post 255°C simulated reflow
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 5 / Term # 8 .
Comp # 1 / Term # 7 .
Comp # 4 / Term # 1 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3101 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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5.3.6. High Temperature/Humidity (55°C/85%RH) post 215°C simulated reflow
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 5 / Term # 7 .
Comp # 4 / Term # 6 .
Comp # 3 / Term # 2 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3161 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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5.3.7. High Temperature/Humidity (55°C/85%RH) post 255°C simulated reflow
Lot
No.
Lot-1
Lot-2
Lot-3
Component # /
Termination #
Comp # 3 / Term # 4 .
Comp # 6 / Term # 7 .
Comp # 1 / Term # 6 .
0 hr
none
none
none
Readpoints
1000 hr 2000 hr
none
none
none
none
none
none
3161 hr
none
none
none
SEM Photo @ Post 4000 hr
Lot-1: No whisker observed
Lot-2: No whisker observed
SEM Photo @ Post 4000 hr
Lot-3: No whisker observed
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4000 hr
none
none
none
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5.3.8. Thermal Cycling (-55/85°C) post 215°C simulated reflow
Lot
Component # /
No.
Termination #
Lot-1 Comp # 2 / Term #
Comp # 3 / Term #
Lot-2 Comp # 3 / Term #
Comp # 6 / Term #
Comp # 6 / Term #
Lot-3 Comp # 1 / Term #
Comp # 5 / Term #
Comp # 5 / Term #
0 cyc
none
none
none
none
none
none
none
none
2.
2.
3.
5.
1.
1.
2.
3.
Readpoints
500 cyc
1000 cyc
29.54µm
29.82µm
24.64µm
32.91µm
22.69µm
23.03µm
23.68µm
30.49µm
19.25µm
25.30µm
19.47µm
34.97µm
1500 cyc
30.11µm
33.56µm
31.52µm
35.11µm
26.37µm
38.40µm
SEM Photo @ Post 500 cyc
SEM Photo @ Post 1000 cyc
Longest whisker growth of 29.54µm
Longest whisker growth of 34.97µm
SEM Photo @ Post 1500 cyc
Longest whisker growth of 38.40µm
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5.3.9. Thermal Cycling (-55/85°C) post 255°C simulated reflow
Lot
Component # /
No.
Termination #
Lot-1 Comp # 1 / Term #
Comp # 5 / Term #
Comp # 5 / Term #
Comp # 6 / Term #
Lot-2 Comp # 4 / Term #
Comp # 5 / Term #
Comp # 3 / Term #
Comp # 5 / Term #
Lot-3 Comp # 4 / Term #
Comp # 6 / Term #
Comp # 6 / Term #
0 cyc
none
none
none
none
none
none
none
none
none
none
none
8.
7.
6.
3.
4.
3.
1.
2.
1.
3.
4.
Readpoints
500 cyc
1000 cyc
14.19µm
21.65µm
13.09µm
17.95µm
12.08µm
9.98µm
20.24µm
16.32µm
15.39µm
18.37µm
12.63µm
13.23µm
-
1500 cyc
25.31µm
27.08µm
22.90µm
18.49µm
19.26µm
20.14µm
SEM Photo @ Post 500 cyc
SEM Photo @ Post 1000 cyc
Longest whisker growth of 15.39µm
Longest whisker growth of 21.65µm
SEM Photo @ Post 1500 cyc
Longest whisker growth of 27.08µm
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5.4. Appendix
5.4.1. Inspection Equipment
5.4.1.1. Optical Microscope
Instrument maker :
Model number
:
Magnification
:
Olympus
SZ40
40-60x
5.4.1.2. SEM
Instrument maker
Model number
Magnification
Hitachi
S3000N
500kx
:
:
:
5.4.2. Reflow Profiles
5.4.2.1. Simulated 215°C Reflow
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5.4.2.2. Simulated 255°C Reflow
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5.4.3. Verification Results of Terminations with Surface Corrosion
5.4.3.1. Surface Corrosion Definition from JEDEC Standard JESD201
Surface Corrosion: A localized change to a silver-colored Sn surface finish
appearing in an optical microscope as non-reflective dark spots ranging in size
from about 25 micrometers on the longest dimension to the entire termination.
5.4.3.2. Verification of Surface Corrosion at different High Temperature/Humidity
Conditions
5.4.3.2.1. High Temperature/Humidity (55°C/85%RH)
Example of Whiskers near the
Surface Corroded Areas
Whisker near
the surface
corroded area
Whisker growth of 15.29µm
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5.4.3.2.2. High Temperature/Humidity (55°C/85%RH) post 255°C simulated
reflow
Example of Whiskers near the
Surface Corroded Areas
Whisker near
the surface
corroded area
Whisker growth of 19.24µm
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