Tin Whiskers, Part 5: Impact of Testing Conditions


Reading time ( words)

In this installment of the tin whisker series, we'll take a look at the impact of testing conditions, and follow-up with this statement from Part 4: “…all-encompassing tests to confirm or deny the culprits for tin whiskers are prohibitively costly and time-consuming…”

The JEDEC Solid State Technology Association (formerly known as the Joint Electron Device Engineering Council) has published several documents that address and/or are related to the testing of tin whiskers, which are good guidelines with which to start.

  • JEDEC Standard No. 201: Environmental Acceptance requirements for Tin Whisker Susceptibility of Tin and Tin Alloy Surface Finishes.
  • JEDEC Standard No. 22A12: Measuring Whisker Growth on Tin and Tin Alloy Surface Finishes.
  • JEDEC Standard No. 22-A104D: Temperature Cycling.

Primarily, three sets of testing conditions are included in the JEDEC documents: ambient temperature storage, elevated temperature storage and temperature cycling, with the following parameters:

Room  Temperature Humidity Storage
30 ± 2°C and 60 ± 3% RH
(1,000 hrs interval inspection/3,000 to 4,000 hours total duration)      

Temperature Humidity Unbiased
60 ± 5°C and 87 + 3/-2% RH
(1,000 hours interval inspection/3,000 to 4,000 hours total duration)      

Temperature Cycling
Lower end temperature: -55 to -40 (+0/-10)°C
Higher end temperature: +85 (+10/-0)°C
(500 cycles inspection /1,000 to 1,500 cycles duration/air to air/5 to 10 minute soak/three cycles per hour)

Read the full column here.


Editor's Note: This column originally appeared in the May 2014 issue of SMT Magazine.

Share

Print


Suggested Items

EIPC Technical Snapshot: Cleanliness

03/01/2021 | Pete Starkey, I-Connect007
John Ling’s invitation to the fifth in EIPC’s series of Technical Snapshots was as droll as we have come to expect: “In these confined days of lockdown, and exhortations to stay at home and only go out for exercise, this only exercises the natural inclination to hop on a ‘plane to some sunshine.’ Although not the same as Factor 20, one of our webinars gives a high degree of protection from harmful ignorance, and you do not have to go out in the cold.”

SMTA Europe Webinar: What Is a Good Solder Joint, and How Can Solder Joints Be Tested?

11/18/2020 | Pete Starkey, I-Connect007
What is a good solder joint? And how can they be tested not only for purposes of process characterisation, optimisation, monitoring, and control but also for ensuring their long-term reliability? Pete Starkey details a webinar organised by the Europe Chapter of SMTA that was presented by Bob Willis, an expert in soldering, assembly technologies, and failure analysis.

Just Ask Eric: Selecting the Right Lead-Free Solder for Your Application

09/15/2020 | I-Connect007 Editorial Team
First, we asked you to send in your questions for Happy Holden and Joe Fjelstad in our “Just Ask” series. Now, it’s Eric Camden’s turn! A regular SMT007 columnist, Eric is a lead investigator at Foresite Inc., an analytical testing and consulting laboratory. As a reliability expert, Eric has worked with many large OEMs and contract manufacturing companies to optimize their manufacturing processes and assist with the identification of electronic hardware failures utilizing various analytical techniques. He also specializes in optimizing PCBA processes and identifying hardware failures through analysis. We hope you enjoy “Just Ask Eric.”



Copyright © 2021 I-Connect007. All rights reserved.