IPC 4101
Lead Free Delamination
Tired of Printed Circuit Board Delamination?
IPC 4101/99 and /124 are the Answer
For some time now the Industry has had to deal with delamination in its Lead Free Boards as it waited for a solution, which would ideally get back to processing the way we did when everything was SnPb. Delamination has occurred primarily on boards made from phenolic laminates, which are used for lead-free and high temp PCBs. While these materials have great thermal properties (Tg > 170C° and Td > 340C°, and conforming to IPC 4101/126/129), they are extremely weak in the fundamental areas of moisture absorption and copper to laminate adhesion.
Moisture Absorption
Standard 130Tg FR4 materials typically have a moisture absorption rate of 0.20% when measured using a 0.028" core material. Phenolic materials often measure moisture absorption of up to 0.45% when measured using the same test vehicle.
Copper to Laminate Adhesion
Standard 130Tg FR4 materials generate peel strength results of 6-9 lbs. Holding all parameters equal, phenolic materials generate peel strength results of 3-4 lbs.
Vapor Escape
These material characteristics take on much more value when you consider the effects of lead-free assembly parameters. Any moisture trapped or absorbed into the PCB will escape during assembly in the form of water vapor, the force of which is measured in psi (pounds per square inch). The vapor will escape from the dielectric from the weakest point in the board, which is typically plated via holes. During standard SnPb assembly at 200C, the vapor pressure is 225 psi. At Pb-Free assembly temperatures (250C), however, the vapor pressure increases to 575 psi.
The Perfect Storm
Combining the increased vapor pressure with phenolic material characteristics of increased moisture absorption and lower adhesion strength gives you a perfect storm capable of ruining entire production runs. In fact, the forces here are so strong that often instead of just blowing vias, entire layers can separate from each other forming delamination areas of 1 square inch or greater.
The Saturn Solution
Our solution is move towards non-phenolic materials, many of which can be found under IPC 4101/99 and /124. To qualify under these IPC categories for lead-free materials, they must have 150Tg and 325Td. While the thermal properties are not as high as the /126 or /129 materials, the mechanical characteristics more than make up for this, as demonstrated by lab tests we commissioned on standard test vehicles.
For more detailed information, please view our webinar we had on this topic at http://www.saturnelectronics.com/webinar_leadfree.htm.
Other Modes/Issues that this improvement will address:
Processing Lead Times
Drill Quality
Total Cost of Ownership
Thursday, November 13, 2008
Sunday, November 9, 2008
Cavity Boards
Cavity Boards
Cavity boards are multilayer designs that expose inner layers to air by requiring pockets of material to be cut out. This requires laminating precut materials, controlled-depth fabrication, tight processing controls, and manufacturing versatility. Also, our standardized Multi-Line tooling systems have been critical in the processing of cavity boards.
Industries Served
Military
RF/Microwave
Automotive - Close Proximity Radar
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Cavity Boards are just one of the many examples Saturn Electronics Corp. offers its customers.
For examples of specific boards offered by Saturn, please follow this link: Examples of Current Technology Applications
Cavity boards are multilayer designs that expose inner layers to air by requiring pockets of material to be cut out. This requires laminating precut materials, controlled-depth fabrication, tight processing controls, and manufacturing versatility. Also, our standardized Multi-Line tooling systems have been critical in the processing of cavity boards.
Industries Served
Military
RF/Microwave
Automotive - Close Proximity Radar
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Cavity Boards are just one of the many examples Saturn Electronics Corp. offers its customers.
For examples of specific boards offered by Saturn, please follow this link: Examples of Current Technology Applications
Lead Free HASL
Lead Free HASL
Lead Free HASL
Definition
SN100CL-
SnCu alloy stabilized with Ni, composed of:
99.3% Tin
<0.7%>
Industry Misconceptions
Predictions of HASL’s Demise
Solderability Issues
Short Duration of Usage
Benefits of Pb-HASL
Lower Copper Erosion on PCB surface and vias
Definition
SN100CL-
SnCu alloy stabilized with Ni, composed of:
99.3% Tin
<0.7%>
Industry Misconceptions
Predictions of HASL’s Demise
Solderability Issues
Short Duration of Usage
Benefits of Pb-HASL
Lower Copper Erosion on PCB surface and vias
Quick Process
Long Shelf Life
Cost
Forgiving
a.) Humidity
b.) Handling
c.) Temperature
Solder Joint Strength
Thickness Criteria
•Generic Thickness Requirement
•Not proper to have only one
-Smaller Pads receive thicker solder deposition
•Solution
• Minimum Alloy Thickness should be segregated by Ranges of Pad Size
Forgiving
a.) Humidity
b.) Handling
c.) Temperature
Solder Joint Strength
Thickness Criteria
•Generic Thickness Requirement
•Not proper to have only one
-Smaller Pads receive thicker solder deposition
•Solution
• Minimum Alloy Thickness should be segregated by Ranges of Pad Size
•Specific Design Set-Up
–Each Design may require its own specific set-up
–Adjustments
•Air Knife Pressure
•Retract Speed
•Dwell Time
–Each Design may require its own specific set-up
–Adjustments
•Air Knife Pressure
•Retract Speed
•Dwell Time
Implementation
•Alloy Control
•Lower copper content of alloy increases solderability
•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 measurement reaches 0.90%
•Alloy Control
•Lower copper content of alloy increases solderability
•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 measurement reaches 0.90%
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:
»Control over the Process
–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:
»Control over the Process
•By implementing these proposed solutions, you can:
–Save up to 30% of your bare board cost
–Increase performance of your products
–Standardize your fab notes to remove risk of non-performing products
–Improve your supply base
–Save up to 30% of your bare board cost
–Increase performance of your products
–Standardize your fab notes to remove risk of non-performing products
–Improve your supply base
For more information on Lead Free Finishes please click here to read more:
PTFE / Hybrid Technologies for PCBs
PTFE / Hybrid Technologies
PTFE / Hybrid Technologies supplier Saturn Electronics Corporation, bare board manufacturer, revved up production of their Advanced Technologies with the addition of the March plasma treatment system allows us to offer our customers PTFE ( or Teflon) based products. These are commonly used in designs with signal integrity concerns. Standard PCB fabricators cannot offer these materials easily due to the plasma treatment these materials typically require. In order to plate this material effectively, the surface must first be activated. We have in-house capability and materials inventory that enables us to best serve our customers. We have also developed the proper laminate recipes that are required to produce hybrid boards using PTFE-based and FR-4 materials together in one design.
Industries served include:
RF/Microwave
Aerospace
Military
Automotive - Close Proximity Radar
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Fine Line and Spacing is just one of the many examples Saturn Electronics Corp. offers its customers.
For examples of specific boards offered by Saturn, please follow this link:
Examples of Current Technology Applications
PTFE / Hybrid Technologies supplier Saturn Electronics Corporation, bare board manufacturer, revved up production of their Advanced Technologies with the addition of the March plasma treatment system allows us to offer our customers PTFE ( or Teflon) based products. These are commonly used in designs with signal integrity concerns. Standard PCB fabricators cannot offer these materials easily due to the plasma treatment these materials typically require. In order to plate this material effectively, the surface must first be activated. We have in-house capability and materials inventory that enables us to best serve our customers. We have also developed the proper laminate recipes that are required to produce hybrid boards using PTFE-based and FR-4 materials together in one design.
Industries served include:
RF/Microwave
Aerospace
Military
Automotive - Close Proximity Radar
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Fine Line and Spacing is just one of the many examples Saturn Electronics Corp. offers its customers.
For examples of specific boards offered by Saturn, please follow this link:
Examples of Current Technology Applications
Controlled Impedance Designs PCBs
Controlled Impedance Designs
Saturn engineers have access to impedance design and stackup software that enables us to verify your line widths, spacing, and stackup prior to CAM.
Based on the proximity of your design to your calculations, we can make adjustments to the design or adjust the stackup to best model the desired impedance. After fabrication, we verify our calculations by performing impedance testing using our Polar CITS500s Controlled Impedance Test System.
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Fine Line and Spacing is just one of the many examples Saturn Electronics Corp. offers its customers.
For examples of specific boards offered by Saturn, please follow this link:
Examples of Current Technology Applications
Fine Line and Spacing PCBs
Fine Line and Spacing PCB supplier Saturn Electronics Corporation, bare board manufacturer, have invested over $200,000 in software, analysis tools, R&D, and equipment to develop systems for fine line and spacing products.
The exciting part of the Printed Circuit Board fabrication business is the integration and application of various fabrication processes for the manufacture of high technology, exotic, and other non-standard products. Fine Line and Spacing is just one of the many examples Saturn Electronics Corp. offers its customers.
The current Fine Line and Spacing system addresses layer-to-layer registration issues by customizing material scale factors for each specific design. Also, we use a cupric etching system, which is essential for creating fine lines on inner layers. As a result, we are currently processing 3 mil line / spacing in prototype quantities (4 mils in production) and have built boards with layer counts in excess of 20 layers.
For examples of specific boards offered by Saturn, please follow this link:
Examples of Current Technology Applications
Thursday, November 6, 2008
Hipot Testing for Heavy Copper PCBs
Heavy Copper Core PCB Hipot Testing
Hipot is an abbreviation for high potential and is used in the testing instruments used to justify electrical insulation in heavy copper printed circuit boards.
Heavy Copper PCB History
At one point in recent history, Saturn Electronics Corporation, a PCB Manufacturing firm, was one of North America's largest users of heavy copper laminate, which we used in the production of power distribution boards for the automotive industry.
Diversifying Core Products
Retaining our skill set in bare board hipot testing and precision etching heavy copper, we applied it to Power Supply. In addition, we applied our registration system to address concerns such as layer to layer winding registration, dry resin, and etch factors commonly seen by users of Heavy Copper PWB Multilayer boards.
PWB Capabilities at a Glance
Heavy Copper PCB Capabilities
We commonly produce boards with 2, 3, 4, & 6 ounce copper with up to 20 layers.
Thermal Management
Additionally, Saturn expertise in Thermal Management for Heavy Copper PCBs leads the Printed Circuit Board industry.
Hipot Testing for PCB Manufacturing
Saturn Electronics Corp. is an industry leader in Hipot Testing for PCB Manufacturing.
Industries Served
Automotive, Medical, Aerospace, Military
Hi-Pot Testing for Heavy Copper PCBs
Hipot is an abbreviation for high potential and is used in the testing instruments used to justify electrical insulation in heavy copper printed circuit boards.
Heavy Copper PCB History
At one point in recent history, Saturn Electronics Corporation, a PCB Manufacturing firm, was one of North America's largest users of heavy copper laminate, which we used in the production of power distribution boards for the automotive industry.
Diversifying Core Products
Retaining our skill set in bare board hipot testing and precision etching heavy copper, we applied it to Power Supply. In addition, we applied our registration system to address concerns such as layer to layer winding registration, dry resin, and etch factors commonly seen by users of Heavy Copper PWB Multilayer boards.
PWB Capabilities at a Glance
Heavy Copper PCB Capabilities
We commonly produce boards with 2, 3, 4, & 6 ounce copper with up to 20 layers.
Thermal Management
Additionally, Saturn expertise in Thermal Management for Heavy Copper PCBs leads the Printed Circuit Board industry.
Hipot Testing for PCB Manufacturing
Saturn Electronics Corp. is an industry leader in Hipot Testing for PCB Manufacturing.
Industries Served
Automotive, Medical, Aerospace, Military
Hi-Pot Testing for Heavy Copper PCBs
Tuesday, November 4, 2008
New Mania Micronic 86 Drilling Machine
New Mania Micronic 86 Drilling Machine
Saturn Electronics Corporation, bare board manufacturer, recently installed the Mania Micronic 86 Drilling Machine into their Romulus, Mi facility.
Six-Spindle PCB-drilling high precision machine
Linear x, y, & Z axis motors 2400 inches per minute table speed
220k RPM Spindle Speed
Drilling of structures with resolutions and density down to +/- 1 mil e.g. for BGA, Flip-Chip Technology and all state of the art materials and structures
Holes diameter range starting from 4 mils
Depth structuring for highly accurate blind via drilling down to +/- 0.5 mil by unique Contact-Drilling feature (CBD)
Options for PCB contour routing or drilling/routing
Free 24-layer PCB Keychain
Saturn Electronics Corporation, bare board manufacturer, recently installed the Mania Micronic 86 Drilling Machine into their Romulus, Mi facility.
Six-Spindle PCB-drilling high precision machine
Linear x, y, & Z axis motors 2400 inches per minute table speed
220k RPM Spindle Speed
Drilling of structures with resolutions and density down to +/- 1 mil e.g. for BGA, Flip-Chip Technology and all state of the art materials and structures
Holes diameter range starting from 4 mils
Depth structuring for highly accurate blind via drilling down to +/- 0.5 mil by unique Contact-Drilling feature (CBD)
Options for PCB contour routing or drilling/routing
Free 24-layer PCB Keychain
Heavy Copper PCBs
Heavy Copper PCBs
Saturn Electronics Corporation Heavy Copper Multilayer Bare Board Manufacturing
At one point in recent history, Saturn Electronics Corporation, bare board manufacturer, was one of North America's largest users of heavy copper laminate, which we used in the production of power distribution boards for the automotive industry. We retained our skill set in precision etching heavy copper and applied it to other industries, namely the power supply industry. Furthermore, we applied our registration system to address concerns such as layer to layer winding registration, dry resin, and etch factors commonly seen by users of heavy copper multilayer boards. We commonly produce boards with 2, 3, 4, & 6 ounce copper with up to 20 layers.
Industries Served
Automotive
Medical
Aerospace
Military
To see more boards offered by Saturn Electronics Corp., please click here to read more.
http://saturnelectronics.com/heavycopperpcb.htm
Saturn Electronics Corporation Heavy Copper Multilayer Bare Board Manufacturing
At one point in recent history, Saturn Electronics Corporation, bare board manufacturer, was one of North America's largest users of heavy copper laminate, which we used in the production of power distribution boards for the automotive industry. We retained our skill set in precision etching heavy copper and applied it to other industries, namely the power supply industry. Furthermore, we applied our registration system to address concerns such as layer to layer winding registration, dry resin, and etch factors commonly seen by users of heavy copper multilayer boards. We commonly produce boards with 2, 3, 4, & 6 ounce copper with up to 20 layers.
Industries Served
Automotive
Medical
Aerospace
Military
To see more boards offered by Saturn Electronics Corp., please click here to read more.
http://saturnelectronics.com/heavycopperpcb.htm
IPC 4101/99/124 and SN100CL – Lead Free HASL
Saturn Shines at PCB West
Bare Board Manufacturer Shows PCB Designers how to Control the Process
Saturn Electronics Corporation, a Bare Board Manufacturer, took its Lead Free Cost Reduction presentation to Santa Clara, CA for the PCB West 2008 from September 14-18. Yash Sutariya delivered the presentation, which claims that utilizing the right combination of materials, finishes, and solders through the IPC 4101/99/124 and SN100CL – Lead Free HASL can produce notable benefits, such as cutting the costs on lead free boards by up to 30% and increasing PCB reliability at the same time.
A crowd approaching close to 40 listened in as Sutariya advanced what he felt were the main reasons for the necessary implementations of the Saturn presentation. Sutariya mentioned the direct cost drivers in the fabrication of Lead Free Boards (high-temp laminates and final finishes) before asserting that the move to Pb-free had created a host of indirect cost drivers as well, which include pre-baking, storage & handling, and an increased scrap rate due to delamination and solderability.
IPC 4101/99/124
The presentation was broken into two sections. The first dealt with Capable Laminates for Lead Free Assembly corresponding to IPC 4101/99 and /124. Sutariya presented numerous effects of the current state of the common callouts. Suppliers lock customers into laminate brand names, and typically phenolic materials that have a moisture absorption up to .45% on 0.028” core; less mechanical strength (interlaminate adhesion); more prone to delamination during assembly; inclination to pad catering on BGA applications. Finally, there were the non-Pb Free capable materials such as FR4. Designers are commonly calling out FR-4 laminates with high Tg values, but without including appropriate Td callouts (time to decomposition at temperature). While FR4 is RoHS Compliant, it is not always capable and 180° Tg does not guarantee adequate Td.
Proposed Solution
Sutariya proposed mid-grade capable Lead Free laminates compliant to IPC 4101/99 or /124 at 150 Tg min. and 325 Td min. Utilizing this approach would lead to higher copper to laminate peel strength, higher inter-laminate adhesion, as well as lower moisture absorption. Also, a 10-20 percent cost saving on the raw materials was promised as a result of these implementations.
The first part of the presentation ended with a promotion for the new FR406HR that is going to address the delamination during the lead free bare board manufacturing process.
SN100CL – Lead Free HASL
The second section dealt with Pb-Free HASL, specifically SN100CL and the Industry misconceptions associated with the discipline such as the predictions of HASL’s inevitable demise, its solderability issues, and the short duration of its usage.
But Sutariya argued that the lower copper erosion on the PCB surface and in the vias was benefit to PCB reliability. Other benefits included: quick process, long shelf life, lower cost, forgiving in regards to humidity, handling and temperature, and finally, Solder Joint Strength.
According to the HALT Test Results (provided by Tim Murphy of Thomson Lab Services and Glenn Sikorcin of Florida CirTech), Lead-Free HASL, with all different solderpastes pooled together, required the most energy (G-force + thermo-cycling) to break the solder joints. Sutariya concluded that lead free HASL solder joints outperform all other surface finishes, including SnPb HASL.
Drawbacks
But there were drawbacks involved pertaining to its planar, which makes it problematic for extremely fine pitch applications. If you’re interested in Past Solderability Issues with SN100Cl, read HASL and Flow: A Lead-Free Alternative from the February 2008 issue of CircuiTree. Furthermore, the SN100CL requires a Thermal Cycle in addition to thermal cycles in the assembly process.
Finally, there still remains no Industry standard regarding the Thickness Acceptability Criteria for SN100CL. As a result, smaller pads receive thicker solder deposition as a result of a Generic Thickness requirement because it is not proper to have just one solder thickness for all pad geometries. Sutariya said the solution was to segregate the minimum alloy thickness by ranges of pad size. By implementing alloy control, lower copper content of alloy increases solderability and the standard drossing of the solder pot is not enough to keep copper below 0.90%.
Sutariya recommended a ¼ - 1/3 solder pot dump once weekly copper content measurement reaches 0.90%.
Specific Design Set-Up
Then Saturn turned its focus to the Design link in the PCB Supply Chain and addressed the need for a specific design set-up. In addition, adjustments would need to be made to air knife pressure, retract speed, and dwell time. In effect, since the operating window is smaller than the SnPB, it is vital for the top of the Supply Chain to take control of the process!
Saturn and Florida CirTech have been utilizing the SN100Cl for over a year and have had no solderability issues at any customer. He attributed this to the value of the Fab Notes that can specify the use of these coupons or range of solder thickness standards.
Sutariya concluded that by doing this, you’d take control of the process by forcing your supplier to meet these specs.
Conclusion
Saturn Electronics’ Corporation’s Lead Free Cost Reduction presentation concludes that through the implementation of one or both of these proposed solutions, one can save up to 30% on their bare board costs while increasing the performance of their products. Additionally, this makes it much easier to standardize fab notes to removable risk of non-performing products.
Sutariya opened the floor to questions from the crowd and attendees, mostly PCB Designers who had very positive feedbacks regarding the recipe Sutariya and Saturn had just shared with them.
During this past summer, Sutariya gave the same presentation through a webinar. Polling questions included:
Have you experienced delamination during Lead Free Assembly?
46% of attendees answered yes
Have you ever tried and subsequently abandoned SN100CL?
6% said yes
12% said no
82% had never even tried it
What is your primary Lead Free Finish?
38% said RoHS Compliant
31% said Immersion Silver
13% said ENIG
13% said Lead Free HASL
6% answered Immersion Tin
PCB West is for PCB engineers, designers, fabricators and managers and includes a five-day conference of more than 35 technical courses.
Saturn Electronics Corporation is a leading manufacturer of high-reliability, and technologically advanced printed circuit boards. Dedicated to quality since our inception, Saturn delivers steadfast manufacturing that ranges from quick-turning elaborate prototypes to scheduled principal volume-production.
Saturn’s adherence to quality resulted in being the first PCB Manufacturer in North America to achieve TS16949 certification.
To view the archived version of this presentation, please email jim@saturnelectronics.com
Bare Board Manufacturer Shows PCB Designers how to Control the Process
Saturn Electronics Corporation, a Bare Board Manufacturer, took its Lead Free Cost Reduction presentation to Santa Clara, CA for the PCB West 2008 from September 14-18. Yash Sutariya delivered the presentation, which claims that utilizing the right combination of materials, finishes, and solders through the IPC 4101/99/124 and SN100CL – Lead Free HASL can produce notable benefits, such as cutting the costs on lead free boards by up to 30% and increasing PCB reliability at the same time.
A crowd approaching close to 40 listened in as Sutariya advanced what he felt were the main reasons for the necessary implementations of the Saturn presentation. Sutariya mentioned the direct cost drivers in the fabrication of Lead Free Boards (high-temp laminates and final finishes) before asserting that the move to Pb-free had created a host of indirect cost drivers as well, which include pre-baking, storage & handling, and an increased scrap rate due to delamination and solderability.
IPC 4101/99/124
The presentation was broken into two sections. The first dealt with Capable Laminates for Lead Free Assembly corresponding to IPC 4101/99 and /124. Sutariya presented numerous effects of the current state of the common callouts. Suppliers lock customers into laminate brand names, and typically phenolic materials that have a moisture absorption up to .45% on 0.028” core; less mechanical strength (interlaminate adhesion); more prone to delamination during assembly; inclination to pad catering on BGA applications. Finally, there were the non-Pb Free capable materials such as FR4. Designers are commonly calling out FR-4 laminates with high Tg values, but without including appropriate Td callouts (time to decomposition at temperature). While FR4 is RoHS Compliant, it is not always capable and 180° Tg does not guarantee adequate Td.
Proposed Solution
Sutariya proposed mid-grade capable Lead Free laminates compliant to IPC 4101/99 or /124 at 150 Tg min. and 325 Td min. Utilizing this approach would lead to higher copper to laminate peel strength, higher inter-laminate adhesion, as well as lower moisture absorption. Also, a 10-20 percent cost saving on the raw materials was promised as a result of these implementations.
The first part of the presentation ended with a promotion for the new FR406HR that is going to address the delamination during the lead free bare board manufacturing process.
SN100CL – Lead Free HASL
The second section dealt with Pb-Free HASL, specifically SN100CL and the Industry misconceptions associated with the discipline such as the predictions of HASL’s inevitable demise, its solderability issues, and the short duration of its usage.
But Sutariya argued that the lower copper erosion on the PCB surface and in the vias was benefit to PCB reliability. Other benefits included: quick process, long shelf life, lower cost, forgiving in regards to humidity, handling and temperature, and finally, Solder Joint Strength.
According to the HALT Test Results (provided by Tim Murphy of Thomson Lab Services and Glenn Sikorcin of Florida CirTech), Lead-Free HASL, with all different solderpastes pooled together, required the most energy (G-force + thermo-cycling) to break the solder joints. Sutariya concluded that lead free HASL solder joints outperform all other surface finishes, including SnPb HASL.
Drawbacks
But there were drawbacks involved pertaining to its planar, which makes it problematic for extremely fine pitch applications. If you’re interested in Past Solderability Issues with SN100Cl, read HASL and Flow: A Lead-Free Alternative from the February 2008 issue of CircuiTree. Furthermore, the SN100CL requires a Thermal Cycle in addition to thermal cycles in the assembly process.
Finally, there still remains no Industry standard regarding the Thickness Acceptability Criteria for SN100CL. As a result, smaller pads receive thicker solder deposition as a result of a Generic Thickness requirement because it is not proper to have just one solder thickness for all pad geometries. Sutariya said the solution was to segregate the minimum alloy thickness by ranges of pad size. By implementing alloy control, lower copper content of alloy increases solderability and the standard drossing of the solder pot is not enough to keep copper below 0.90%.
Sutariya recommended a ¼ - 1/3 solder pot dump once weekly copper content measurement reaches 0.90%.
Specific Design Set-Up
Then Saturn turned its focus to the Design link in the PCB Supply Chain and addressed the need for a specific design set-up. In addition, adjustments would need to be made to air knife pressure, retract speed, and dwell time. In effect, since the operating window is smaller than the SnPB, it is vital for the top of the Supply Chain to take control of the process!
Saturn and Florida CirTech have been utilizing the SN100Cl for over a year and have had no solderability issues at any customer. He attributed this to the value of the Fab Notes that can specify the use of these coupons or range of solder thickness standards.
Sutariya concluded that by doing this, you’d take control of the process by forcing your supplier to meet these specs.
Conclusion
Saturn Electronics’ Corporation’s Lead Free Cost Reduction presentation concludes that through the implementation of one or both of these proposed solutions, one can save up to 30% on their bare board costs while increasing the performance of their products. Additionally, this makes it much easier to standardize fab notes to removable risk of non-performing products.
Sutariya opened the floor to questions from the crowd and attendees, mostly PCB Designers who had very positive feedbacks regarding the recipe Sutariya and Saturn had just shared with them.
During this past summer, Sutariya gave the same presentation through a webinar. Polling questions included:
Have you experienced delamination during Lead Free Assembly?
46% of attendees answered yes
Have you ever tried and subsequently abandoned SN100CL?
6% said yes
12% said no
82% had never even tried it
What is your primary Lead Free Finish?
38% said RoHS Compliant
31% said Immersion Silver
13% said ENIG
13% said Lead Free HASL
6% answered Immersion Tin
PCB West is for PCB engineers, designers, fabricators and managers and includes a five-day conference of more than 35 technical courses.
Saturn Electronics Corporation is a leading manufacturer of high-reliability, and technologically advanced printed circuit boards. Dedicated to quality since our inception, Saturn delivers steadfast manufacturing that ranges from quick-turning elaborate prototypes to scheduled principal volume-production.
Saturn’s adherence to quality resulted in being the first PCB Manufacturer in North America to achieve TS16949 certification.
To view the archived version of this presentation, please email jim@saturnelectronics.com
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