5th International Symposium

on Tin Whiskers (2011)

September 14-15, 2011
Colony Ballroom, Stamp Student Union
University of Maryland
College Park, MD

Scope

Tin whiskers present a unique challenge to the electronics industry. There have been numbers of electronics failures in the market caused by tin whiskers since 1940s. After 2000, as a result of the global transition to lead-free electronics, the majority of the electronic component manufacturers are now using pure tin or tin-rich alloys for terminal and lead finishes. The increased used of tin based lead-free finishes and materials, focused concern and research on tin whiskers particular for long life and mission critical applications, such as space, aviation, and implantable medical devices.

A tin whisker is a conductive tin crystal, which can spontaneously grow from tin based lead-free finished surfaces even at room temperature, often in a needle-like form. Oxidation in humid atmosphere, corrosion, intermetallic formation, stress under thermal cycling, external pressure in fine pitch connectors and electromigration have been shown to promote whisker formation. However, acceleration models for whisker growth are very limited or not existent.

Tin whisker studies are being conducted by universities, companies and research organizations. Whisker research includes examining the fundamentals of whisker growth, the influence of the plating process, the influence of materials sets, the environmental stress drivers, methods for estimating whisker failure risk, and strategies for mitigating whisker failure risk.

The goal of this symposium is to bring together the worlds experts, in the field of tin whiskers to discuss the state of research on tin whiskers. This symposium will cover case histories, theories of tin whisker growth, experiments and results, risk evaluation methods and risk mitigation strategies. Attendees will be able to discuss the current state of knowledge on the growth, risk and mitigation strategies, whereby they can develop effective qualification and mitigation procedures for their products. All attendees are free to join us in this symposium.

Attendee Registration for Web Access

Please note, CALCE EPSC members can access these presentations with there existing Web Accounts.

Contact

Dr. Michael Osterman, CALCE, University of Maryland, osterman@calce.umd.edu


Speaker Bios

Presentations

Wednesday September 14th

8:15am

Welcome

Michael Osterman, CALCE

     
8:35am

Electrical Failure of an Accelerator
Pedal Position Sensor Caused by
Tin Whiskers

Henning Leidecker, NASA

     
9:15am

Assessment of Tin Whisker Induced Metal Vapor Arcing

Sungwon Han, CALCE

   

MVA Movie 50V 760torr

MVA Movie 50V 70torr
 

 
9:45am

Update of GEIA Standard

Anduin Touw, Boeing

     
10:15am Break  
     
10:30am

Evolving Stress State due to Whisker Growth

Elizabeth N. Hoffman, Savannah River National Laboratory

     
11:00am

Crystallographic Analysis of Tin Whiskers with
SEM/EBSD

Donald F. Susan, Sandia National Labs

     
11:30am

Statistical Relevance of Identification and Counting Procedure for Tin Whiskers and Hillocks in Comparison to the JEDEC JESD 22-A121A

Nick Clore, Purdue University

     
12:00pm Lunch  
     
1:00pm

Microstructure Investigations of Whiskering Sn films Electroplated on Cu Substrates Using 2Ddetector X-ray Diffraction

Jendrik Stein, Robert Bosch

     
1:30pm

NIST Research Related to Tin Whisker

Maureen Williams, NIST
     
2:00pm

Controlling Direction of Strain Energy Driving Forces Responsible for Whisker Growth

Jamin Pillars, University of New Mexico, and
Graham Yelton,
Sandia National Labs
     
2:30pm Break  
     
2:45pm

The Role of Ionic Contamination and Tin Oxide Interactions in Tin Whisker Initiation

David Hillman, Rockwell Collins
     
3:15pm Examination of Conformal Coating Coverage Michael Osterman,
CALCE
     
3:45pm

Whisker-Impenetrable Metal Cap Process for Electronic Assemblies

Gordon Davy,
LDF Coatings, LLC

     
4:15pm Wrap-Up Discussion  
     
 

Thursday September 15th

8:30am

Welcome

Michael Osterman, CALCE
     
8:45am

Evaluation of Conformal Coating for Mitigation of Tin Whisker Growth

Tsuyoshi Nakagawa, Nippon Avionic Co.

     
9:15am

Adhesion and Puncture Strength of Conformal Coating Used to Mitigate Tin Whisker Growth

Yong Sun, CALCE

     
9:45am Evaluation of Mitigation of Tin Whisker Growth for Lead-free Parts with Ceramic Coating Mikihiko Urano, HIREC
     
10:15am Break  
     
10:30am SERDP Tin Whisker Testing and Modeling Project Stephan Meschter, BAE
     
11:00am

SERDP Tin Whisker Screening Experiment Results

Polina Snugovsky,
Celestica
     
11:50am Lunch  
     
12:50pm Effects of Sn layer microstructure, composition and mechanical properties on whisker nucleation and growth Nitin Jadhav, Fei Pei, Eric Chason,
Brown University
     
1:20pm New perspectives on tin whiskers based on atomistic modeling Brooke Hatfield and
T. Glenn Yuguchi, Raytheon Missile Systems
     
1:50pm Wrap-Up Discussion