Monday, February 1, 2010
Counterfeit Prevention and Detection Strategy
One of the limitations of the current conversation on counterfeits is the failure to identify a systematic approach to risk mitigation. By incorporating the probability of counterfeit exposure, the purchase volumes, and the cost of failure, this strategic tool can be used to identify the detection and avoidance techniques that provide the greatest return on investment. For more information, please contact Greg Caswell, gcaswell@dfrsolutions.com.
Sunday, January 31, 2010
DfR in Huntsville, AL and Atlanta, GA (February 16)
DfR in Huntsville, AL and Atlanta, GA (February 16)
DfR Solutions will be visiting companies in Huntsville, AL and Atlanta, GA in mid-Febuary. If you and your associates are interested in an onsite visit and/or presentation, please contact Carrie Sharik-Ernest at csharik@dfrsolutions.com or Vaughn Carlson at vaughanc@valueeng.com.
DfR Solutions will be visiting companies in Huntsville, AL and Atlanta, GA in mid-Febuary. If you and your associates are interested in an onsite visit and/or presentation, please contact Carrie Sharik-Ernest at csharik@dfrsolutions.com or Vaughn Carlson at vaughanc@valueeng.com.
Wednesday, January 27, 2010
DfR at RAMS and Chesapeake, MD iMAPS This Week
RAMS (San Jose, CA: January 25-27)
Jim McLeish, CRE, will be in San Jose, CA, at the Reliability and Maintainability Symposium (RAMS) in late January. Jim will be presenting a paper entitled, " Enhancing MIL-HDBK-217 Reliability Predictions with Physics of Failure (PoF) Methods," in which he will discuss potential enhancements to the handbook using Physics of Failure methods.
IMAPS Chesapeake Conference Meeting (Columbia, MD: January 27)
Dr. Craig Hillman will be presenting " Manufacturing and Reliability Challenges with QFN Packages in Pb and Pb-Free Environments,” at the upcoming IMAPS conference. For more information on this topic, please contact Craig Hillman at chillman@dfrsolutions.com
Jim McLeish, CRE, will be in San Jose, CA, at the Reliability and Maintainability Symposium (RAMS) in late January. Jim will be presenting a paper entitled, " Enhancing MIL-HDBK-217 Reliability Predictions with Physics of Failure (PoF) Methods," in which he will discuss potential enhancements to the handbook using Physics of Failure methods.
IMAPS Chesapeake Conference Meeting (Columbia, MD: January 27)
Dr. Craig Hillman will be presenting " Manufacturing and Reliability Challenges with QFN Packages in Pb and Pb-Free Environments,” at the upcoming IMAPS conference. For more information on this topic, please contact Craig Hillman at chillman@dfrsolutions.com
Tuesday, January 26, 2010
DfR Solutions Welcomes Dr. Randy Kong
DfR Solutions is proud to announce the hiring of Dr. Randy Kong, an industry renowned expert in the fields of process reliability qualification, component engineering, and meeting OEM reliability requirements. Prior to joining DfR Solutions, Dr. Kong was responsible for establishing a failure analysis lab through his work at Hewlett-Packard. Most recently at Microsoft, Randy co-founded the reliability engineering group for the hardware division, led the development of a component engineering database which captured application-specific requirements, and established quality/reliability processes which emphasized DfX principals. Randy holds a BS in Electrical Engineering from Tsinghua University and has a Ph.D. in Physics from the Graduate Center of City University of New York.
For more information or to schedule an onsite visit at your facility, please contact Dr. Kong at rkong@dfrsolutions.com.
For more information or to schedule an onsite visit at your facility, please contact Dr. Kong at rkong@dfrsolutions.com.
Monday, January 25, 2010
Cheryl Tulkoff appears in Advancing Microelectronics 2009, Issue 6 November/December
On page 35, a photo of me giving a presentation to the Central Texas Chapter on "Manufacturability and Reliability Challenges with QFN" made it into the new iMAPS Advancing Microelectronics magazine.
The November/December 2009 issue features 4 technical articles on: NanoBond Assembly - A Rapid, Room Temperature Soldering Process; Can Current EDA Packaging Tools Meet the Demands of Ever-Changing 3D Packaging Technologies?; Thermal Management for LED Pico Projectors; and Conformal 3D Electronics: the Future of Consumer and Medical Products.
A link to the magazine can be found by clicking here.
For more information of future Central Texas events, please click HERE.
The November/December 2009 issue features 4 technical articles on: NanoBond Assembly - A Rapid, Room Temperature Soldering Process; Can Current EDA Packaging Tools Meet the Demands of Ever-Changing 3D Packaging Technologies?; Thermal Management for LED Pico Projectors; and Conformal 3D Electronics: the Future of Consumer and Medical Products.
A link to the magazine can be found by clicking here.
For more information of future Central Texas events, please click HERE.
Sunday, January 24, 2010
DfR QFN articles ranked as "Most Popular Articles of 2009" in SMT Week!
Our two QFN articles ranked as the "Most Popular Articles of 2009" in SMT Week. To read them or to read any of the other popular articles you may have missed, check out the following link:
SMT Weekly Newsletter
SMT Weekly Newsletter
Monday, December 21, 2009
The Tin Commandments - Just in Time for the Holidays!
The Tin Commandments
Copyright © DfR Solutions, College Park, MD, 2009 All Rights Reserved.
1. Thou shalt have no Lead (Pb) in the solder for EU (among other) applications.
The European Union, the USA, most industrialized Asian nations, etc., all require that all commercial products to be sold in their Countries must have hazardous materials (like Mercury and Lead) removed from PC Boards. The deadline for compliance was 2006 with elimination of some exemptions forthcoming. The most common Pb-free solder alloys consist mostly of tin with small additions of silver an copper. Some question why the electronics industry, which accounts for less than 0.1% of the lead in land-fills, was targeted by the EU. It matters not, since the train has now left the station. Even exempt industries such as telecommunications, medical, and the military are finding it increasingly difficult to continue using Pb.
2. Thou shalt not make Tin (Sn) whiskers that will cause short circuits.
Pure Tin tends to make “whiskers”, a short growth from the main body of Tin, and small Tin lands make the whiskers grow the most. Historically 1-2% Lead (Pb) was used to prevent whiskering in tin coatings. Various methods are used to mitigate whisker growth without use of Pb but the only way to prevent it is use coatings such as Pd or Au.
3. Thou shalt not take Pb-free ball grid array components and solder them onto a Pb-based solder pad.
Though it is not impossible to achieve a reliable mixed solder joint, the component must reach 230°C to do so. The PCB and other components must be designed to survive the higher temperature.
4. Remember the Sabbath Day (and 2nd and 3rd shift workers).
Building high quality products with Pb-free solder requires consistently hitting a much more narrow process window. Your off hour workers must be trained just as well as the 1st shift workers.
5. Honor thy supplier qualification and process control requirements.
In order to ensure that you get the materials you specify, trust the documentation from your suppliers.
6. Thou shalt not kill your boards with the higher temperatures in reflow ovens in a Lead-free application.
Notice that the temperature difference in most SMT re-flow ovens between a Leaded Solder and a Lead-free Solder is about 35 degrees C. Specifying the appropriate board properties is critical to prevent delamination, warping, cracked vias, or worse. Components must also be specified to survive reflow conditions (JST-020C should be followed religiously).
7. Thou shalt not mate female Gold connectors with male Tin connectors (or vice versa).
The reason for this is because of the inter-metallic that is made between Gold and Tin (or a solder Tin alloy) when they are repeatedly rubbed together. Build up of this inter-metallic can cause an open connection. If you need a good connection, use gold with gold. Tin with tin is also acceptable for applications where fretting is not a concern.
8. Thou shalt not steal published quality and reliability data.
Since your environment is unique to you, don’t expect to get similar results when you application differs from that of published reports.
9. Thou shalt not bear with the same rework standards after going Lead-free.
Experience shows that the re-work stations in most PC Board manufacturing facilities are often overlooked as an essential area that must be controlled. Hitting the small process window requires well controlled rework profiles and often new equipment. “Touch up” areas are becoming extinct because of the extra heat of the solder iron that’s required in a Lead-free process. The quality of all rework processes should be validated with close inspection.
10. Thou shalt not covet the Tin mines in China, Indonesia, and South America.
It’s true that our planet’s main resources for Tin are in China (40%), Indonesia (20%) and South America (20%) and yet it seems that Chinese companies are buying up another Tin mine every week. Tin is available in mines across our world, but the best mines are not in the Americas or Europe.
Copyright 2009 by DfR Solutions and VALUE Engrafting. All Rights Reserved.
Copyright © DfR Solutions, College Park, MD, 2009 All Rights Reserved.
1. Thou shalt have no Lead (Pb) in the solder for EU (among other) applications.
The European Union, the USA, most industrialized Asian nations, etc., all require that all commercial products to be sold in their Countries must have hazardous materials (like Mercury and Lead) removed from PC Boards. The deadline for compliance was 2006 with elimination of some exemptions forthcoming. The most common Pb-free solder alloys consist mostly of tin with small additions of silver an copper. Some question why the electronics industry, which accounts for less than 0.1% of the lead in land-fills, was targeted by the EU. It matters not, since the train has now left the station. Even exempt industries such as telecommunications, medical, and the military are finding it increasingly difficult to continue using Pb.
2. Thou shalt not make Tin (Sn) whiskers that will cause short circuits.
Pure Tin tends to make “whiskers”, a short growth from the main body of Tin, and small Tin lands make the whiskers grow the most. Historically 1-2% Lead (Pb) was used to prevent whiskering in tin coatings. Various methods are used to mitigate whisker growth without use of Pb but the only way to prevent it is use coatings such as Pd or Au.
3. Thou shalt not take Pb-free ball grid array components and solder them onto a Pb-based solder pad.
Though it is not impossible to achieve a reliable mixed solder joint, the component must reach 230°C to do so. The PCB and other components must be designed to survive the higher temperature.
4. Remember the Sabbath Day (and 2nd and 3rd shift workers).
Building high quality products with Pb-free solder requires consistently hitting a much more narrow process window. Your off hour workers must be trained just as well as the 1st shift workers.
5. Honor thy supplier qualification and process control requirements.
In order to ensure that you get the materials you specify, trust the documentation from your suppliers.
6. Thou shalt not kill your boards with the higher temperatures in reflow ovens in a Lead-free application.
Notice that the temperature difference in most SMT re-flow ovens between a Leaded Solder and a Lead-free Solder is about 35 degrees C. Specifying the appropriate board properties is critical to prevent delamination, warping, cracked vias, or worse. Components must also be specified to survive reflow conditions (JST-020C should be followed religiously).
7. Thou shalt not mate female Gold connectors with male Tin connectors (or vice versa).
The reason for this is because of the inter-metallic that is made between Gold and Tin (or a solder Tin alloy) when they are repeatedly rubbed together. Build up of this inter-metallic can cause an open connection. If you need a good connection, use gold with gold. Tin with tin is also acceptable for applications where fretting is not a concern.
8. Thou shalt not steal published quality and reliability data.
Since your environment is unique to you, don’t expect to get similar results when you application differs from that of published reports.
9. Thou shalt not bear with the same rework standards after going Lead-free.
Experience shows that the re-work stations in most PC Board manufacturing facilities are often overlooked as an essential area that must be controlled. Hitting the small process window requires well controlled rework profiles and often new equipment. “Touch up” areas are becoming extinct because of the extra heat of the solder iron that’s required in a Lead-free process. The quality of all rework processes should be validated with close inspection.
10. Thou shalt not covet the Tin mines in China, Indonesia, and South America.
It’s true that our planet’s main resources for Tin are in China (40%), Indonesia (20%) and South America (20%) and yet it seems that Chinese companies are buying up another Tin mine every week. Tin is available in mines across our world, but the best mines are not in the Americas or Europe.
Copyright 2009 by DfR Solutions and VALUE Engrafting. All Rights Reserved.
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