1. 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

2. 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

3. 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

4. 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

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

6. 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

7. 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

8. 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

9. 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:
Underfill as an example of ruggedization (from IPC)
Unrestricted Content
Unrestricted Content

10. 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

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