Lead Free Cost Reduction webinar dealing with RoHS compliant laminates and final finishes pertaining to PCB manufacturing to included design, fabrication, and assembly.

1. Lead Free Cost Reduction
Available with Audio at:
www.SaturnElectronics.com/webinar_leadfree.htm
Email Jim@saturnelectronics.com for the password
Thank you for your inquiry into the Lead Free Cost Reduction PowerPoint Presentation.
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2. Lead Free
L dF
Cost Reduction

3. Direct Cost Drivers
Hi h T L i t
–High Temp Laminates
Final Finishes
–Final Finishes
3

4. Indirect Cost Drivers
Increased Scrap Rate
–Increased Scrap Rate
• De-lamination
• Solderability
Pre Baking
–Pre‐Baking
g g
–Storage / Handling
4

5. Section 1
S ti
Pb‐free
bf
Assembly
sse b y
Capable Laminate 5

6. IPC 4101/99 /124
from
Isola Group/ Insulectro
6

7. Current State
Audience Poll……
C C ll
–Common Callouts
• IS410 / 370HR
• FR4
• RoHS Compliant
• 180ºC Tg
• 340ºC Td
• IPC 4101/126 or /129
7

8. Current State ( )
(cont.)
Audience Poll……
• Effect of Common Callouts
1. Locked in to laminate by brand name
2. Typically Phenolic
2 Typically Phenolic materials
• Moisture absorption up to .45% on 0.028” core
• Less mechanical strength (interlaminate adhesion)
• More prone to de‐lamination during assembly
• Prone to pad cratering on BGA applications
8

9. • Have you experienced delamination during Lead Free
Assembly?
• Yes
• No
9

10. Poll Results
10

11. Current State ( )
(cont.)
3. Non Pb Free capable material
3. Non‐Pb Free capable material
• FR4 is not capable
• RoHS Compliant can include standard FR4
• 180Tg does not guarantee adequate Td
11

12. Proposed Solution
• Mid‐Grade Pb‐free capable
laminates
– IPC 4101 / 99 (filled) or /124 (unfilled)
• 150 Tg min.
T i
• 325 Td min.
12

13. Benefits
– 15‐20% Cost Savings on Raw Materials
– Lower Moisture Absorption (0 10%‐
Lower Moisture Absorption (0.10%
0.25%)
– Higher interlaminate adhesion
• Peel strength
• T‐288 >10 minutes
– Higher Copper to Laminate peel strength
13

14. Results
(using Isola IS400 as example)
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15. Results
Test Group Results
Decomposition Temperature
Test 1 of 2
Method of Determination: TGA
Decomposition Temperature: 331 C
Ramp Rate: 10 C/ min
Test 2 of 2
est o
Method of Determination: TGA
Decomposition Temperature: 334 C
Ramp Rate:
Ramp Rate: 10 C/ min
10 C/ min
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16. TGA
16

17. Results
Test Group
Test Group Results
Delta TG
Test 1 of 1
Method of Determination: DSC
TG Scan 1: 150 C
TG Scan 2: 154 C
Delta Tg: 4 C
Ramp Rate: 20 C/min
Analysis Method: Half Height
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18. DSC
DSC – (A)
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19. DSC – (B)
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20. Results
Test Group Results
Time to Decomposition at Temperature
Test 1 of 2
Method of Determination: TMA
Time to Decomposition: 35.9 minutes
Isothermal Temperature: 260 C
Test 2 of 2
Method of Determination: TMA
Time to Decomposition: 10.4 minutes
Isothermal Temperature:
Isothermal Temperature: 288 C
288 C
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21. T-260
T 260
21

22. T‐288
T 288
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23. Results
Test G
T Group Results
R l
Weight Loss % by TGA
Test 1 of 1
Percent Weight Loss: 0.2%
Start Temperature: 0º C
Stop Temperature:
Stop Temperature: 0º C
0º C
Comments: Moisture Method
% Weight Loss = 0.1717%
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24. Moisture Absorption (A)
24

25. Results
Test Group Results
Peel Strength
Condition: Condition A
Peel Strength Side 1: 11.73 lbs/in
Peel Strength Side 2:
Peel Strength Side 2: 10.95 lbs/in
10.95 lbs/in
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26. 6‐X Reflow
6 X Reflow
Pb‐free Assembly Temperature
Pb f bl
– One board, 3 array
– One 4.25 x 9.5L”, Two 4.75 x 9.5L”
– Thickness + 0.063 3
– TGA moisture = 0.2534%
– 260° Peak Temperature
p
26

27. 27

28. Results
Conditioning As Received
Board # 14753-1
Material IS400
Thickness (mil)
( ) 0.063
Conveyor Speed (cm/min) 48
Peak Mean Temp (°C) 259.8
TC Temp Range
TC Temp Range 3.4
Rising time between 150C ‐ 200C 66.67 (sec)
Time above 217 101
Time above
Time above 255 19.69
19 69
Passes to Fail 6x‐Pass
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29. Coming Soon – FR406HR
29

30. Section 2
Pb‐Free
Pb Free
HASL
Audience Poll
30

31. • Have you ever tried and subsequently abandoned SN100CL?
• Yes
• No
• Never even tried it.
31

32. Poll Results
32

33. Definition
SN100CL
‐this is a SnCu alloy stabilized with Ni,
composed of:
• 99.3% Tin
• <0.7% Copper
<0 7% Copper
• 0.05% Nickel
• 60 ppm Germanium
pp
33

34. Industry
y
Misconceptions
• Predictions of HASL’s Demise
• S ld bili I
Solderability Issues
• Short Duration of Usage
34

35. Benefits
1. Lower Copper Erosion on PCB surface and vias
2. Quick Process
Q i k P
3. Long Shelf Life
4. Cost
(< 1/14 ENIG)
5. Forgiving
a.) Humidity
y
b.) Handling
c.) Temperature
6. Solder Joint Strength
35

36. Results
( using Florida CirTech HALT example )
Highly Accelerated Life Test
36

37. Benefits – Solder Joint Strength
J g
HALT Test Results
37

38. Benefits –HALT Test Results
38

39. Benefits
39

40. Benefits
40

41. HALT Test Results
Lead-Free HASL, with all different solderpastes pooled together, required the most energy
(G-force + thermo-cycling) to break the solder joints.
Since this test takes out the failure effect of the components, we can conclude that lead-free
HASL solderjoints outperform all other surface finishes, including SnPb HASL.
Our thanks go to Tim Murphy of Thomson Lab Services and Florida CirTech for the report
abstract.
For a full report, please contact James Kelch @ jim@saturnelectronics.com
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42. Drawbacks
• Not Planar
• Not Ideal for extremely fine pitch applications
• Past Solderability Issues
• HASL and Flow: A Lead-Free Alternative
addresses this in the February ’08 issue of
Request a copy from James Kelch or visit the
Lead Free Resource Center on our website.
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43. Drawbacks, cont.
Drawbacks cont
• Thermal Cycle
– SN100CL requires a Thermal Cycle in addition to
Thermal Cycles in Assembly
• No Set Industry Standards
– Neither the IPC nor Nihon Superior had developed a
Thickness Acceptability Criteria when SN100CL was
introduced Audience Poll
43

44. Polling Question
P lli Q ti
44

45. • What is your primary Lead Free finish?
• ENIG
• Lead Free HASL
• Immersion Silver
• Immersion Tin
• RoHS Compliant
45

46. Poll Results
46

47. No Standard
No Standard ‐ Solutions
Trigger Event
Solderability Issue at Customer
y
47

48. No Standard ‐
No Standard Solutions
• Goal
– Establish a Set Criteria
48

49. Thickness Criteria
• Generic Thickness Requirement
q
• Not proper to have only one
– Smaller Pads receive thicker solder deposition
• Solution
• Minimum Alloy Thickness should be
segregated by Ranges of Pad Size
49

50. Pad Size ( s) Min. Thickness
ad S e (mils) c ess
126 x 131 50 uin
29 x 83 80 uin
17 x 36 100 uin
50

51. Implementation
• Alloy Control
• Lower copper content of alloy increases solderability
pp y y
• Standard Drossing of solder pot is not enough to
keep copper content below 0.90%
• Recommend a 1/4 ‐ 1/3 solder pot dump once weekly
1/4 ‐
measurement reaches 0.90%
51

52. Implementation
• Specific Design Set‐Up
Specific Design Set Up
– Each Design may require its own specific set‐up
– Adj t
Adjustments
t
• Air Knife Pressure
• Retract Speed
• Dwell Time
52

53. Implementation
• In effect, since the operating window is
smaller than with SnPB,…….
CONTROL The PROCESS!!!
53

54. SN100CL
Study Conclusion
• No Solderability Issues at any customer
– Fab Notes
• Fab notes can specify the use of these coupons
or range of solder thickness standards
– Forcing your supplier to meet these specs will give
you:
C l h P
»Control over the Process
54

55. Conclusion
• By implementing one or both of these
proposed solutions, you can:
proposed solutions you can:
– Save up to 30% of your bare board cost
–IIncrease performance of your products
f f d
– Standardize your fab notes to remove risk of
non‐performing products
f i d t
– Improve your supply base
55

56. • To view the archived version of this presentation,
please email jim@saturnelectronics.com
• To sign up for our upcoming Lead Free Newsletter,
please email jay@saturnelectronics.com
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57. Thank You!
Saturn Electronics Corporation
would like to thank our presenters:
 Dave Coppens / Isola
 Terry Staskowicz / Insulectro
 Glenn Sikorcin / Florida CirTech
*Don’t forget to visit the Lead Free Resource Center
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