Pb-Free Design/Implementation Guide Team Update for PERM 33 Tony Rafanelli 8-81D Team Lead July 26, 2017 12/29/2018 Unrestricted Content   Unrestricted Content  

Agenda Who Are We? In the Beginning Where We Are Now? Vision Approach Where We Are Now? Status of the Guide Plan Forward Questions 12/29/2018 Unrestricted Content   Unrestricted Content  

Average of ten (10) persons per meeting Who Are We? Close to fifty (50) different participants (globally) Government/military organizations Academic and non-profit organizations Private companies (aerospace, defense, suppliers) Average of ten (10) persons per meeting 12/29/2018 Unrestricted Content   Unrestricted Content  

Pb In the Beginning….. Vision Approach Bob Gregory (Rolls Royce NA, retired) generated a strawman list “Pb-free things that keep me up at night..” Approach Provide a collection of guidelines dealing solely with Pb-free Not a comprehensive electronics design guide A “delta” guide, i.e. differences between Pb-free and SnPb Implementation aspect added in May 2017 Pb Unrestricted Content   Unrestricted Content  

Where We Are Now 12/29/2018 Unrestricted Content   Unrestricted Content  

Where We Are Now From Section 2.1 of the Guide Guide intent is to address ‘delta’ differences between SnPb and Pb-free solder technologies Any redundant information may be result of completion or context “Delta” differences categorized as: Typically poorer wetting ability Differences in appearance and inspection criteria Typically higher melting temperature Potential tighter process window for repair/rework Increased potential of tin whiskers Unrestricted Content   Unrestricted Content  

Content Highlights Comprehensive basic technical knowledge section Pb-free Solder, Pb-free Interconnections, and Tin Whiskers Risks Mitigations References/Resources Relationships of Pb-free with PWBs Plating/Finishing issues Conductive Filament Formation Pb-free crack in interconnection (Courtesy of DfR Solutions) Tin Whiskers (Courtesy of NASA) Unrestricted Content   Unrestricted Content  

Content Highlights cont’d Comprehensive basic technical knowledge section cont’d Product Qualification Relationship with Manufacturing Processes Soldering Supply Chain Control Obsolescence Management Configuration Management Some Pb-free soldering anomalies (from L to R): fracture, projection, fillet lift (from IPC-A-610, Courtesy of IPC) Unrestricted Content   Unrestricted Content  

Content Highlights cont’d Implementation (Design Strategies) Product Design Risk Management (e.g. underfills) Customer Risk Management Design Process Flow Align with basic product development process – highlight incorporation of Pb-free concerns/mitigations From Proposal stage through Product Support Reference for underfill graphic: https://www.google.com/search?q=IPC,+underfill+photos&safe=active&hl=en&site=webhp&tbm=isch&imgil=Dl1LCUU9E80SpM%253A%253BI4o5l3b3856edM%253Bhttp%25253A%25252F%25252Felectroiq.com%25252Fblog%25252F2001%25252F12%25252Fbga-underfills%25252F&source=iu&pf=m&fir=Dl1LCUU9E80SpM%253A%252CI4o5l3b3856edM%252C_&usg=__Rumd1f5fEMleBqIZhuRPg3UE3UU%3D&biw=1680&bih=843&ved=0ahUKEwiGvpD9h5PVAhUo6YMKHdJ1AZIQyjcIPQ&ei=5B1uWYa8L6jSjwTS64WQCQ#imgrc=xwAW_Sn0peVc7M:&spf=1500388846421 Underfill as an example of ruggedization (from IPC) Unrestricted Content   Unrestricted Content  

Status of the Guide Reviews, at all levels, completed Development team inputs done PERM Council review done Industry SMEs reviews done Dr. Reza Ghaffarian (JPL) Dr. Richard Coyle (Nokia) Dr. Martin Anselm (Rochester Institute of Technology) Guide now under going IPC Industry Review Release date dependent upon IPC review comments Team meetings have been suspended for now 12/29/2018 Unrestricted Content   Unrestricted Content  

THANK YOU ! Questions ? 12/29/2018 Unrestricted Content   Unrestricted Content