OSP and Selective Electroless Nickel for Mixed-Metal Finish PWBs and BGA Substrates


Reading time ( words)

The documentation relating to the requirements for alternative surface finishes have been well publicized at many industry forums. Pressure to eliminate lead in electronics assemblies is forcing fabricators and OEMs to reevaluate their surface finish and joint attachment procedures. Many of the requirements, in fact, are obvious. Regardless, the PWB fabrication industry needs to work closely with contract manufacturers and end users to fully appreciate the true impact of technology trends. These trends are significant and include:

  • Surface mount continues to increase at the expense of through-hole with finer and finer features.
  • The use of non-tin/lead coatings and surface finishes will increase. Surface finishes such as electroless nickel/immersion gold, OSP and immersion tin will be utilized.
  • With political movements toward banning lead in all electronic assemblies gaining significant  momentum, lead-free solder pastes and wave solder materials will be adopted.
  • The need for more robust solderable finishes under extreme environmental conditions including corrosive atmospheres.
  • The alternative surface finishes must perform through multiple thermal cycles with less active pastes and fluxes.
  • The use of multiple metal finishes on the same bare board will place new emphasis on the compatibility of coating with each other, and the actual assembly module.
  • Increased I/O demand and reduced lead pitch will require much tighter controls over the processes used to fabricate the bare board.

Read the full article here.

Editor’s Note: This article originally appeared in the February 2015 issue of The PCB Magazine

Share


Suggested Items

IPC 6012-DA Revisions: The Approach to Cleanliness, Thickness, Inspection, and Wicking

04/13/2018 | Jan Pedersen, ELMATICA
IPC’s Automotive Addendum task group was started in November 2014 and the first edition of IPC 6012-DA was released in April 2016. We are now working on the revised version, and expect a release in Q2 2018. As standards need to evolve, develop and follow the needs of the industry, this work is continuous.

Conversations on the Floor: IPC APEX EXPO 2018

04/11/2018 | Steve Williams, The Right Approach Consulting LLC
This year’s show was one of the best in recent history, both in attendance and enthusiasm. The exhibit floor was sold out, and every single person I talked to was extremely optimistic about business in 2018. What follows are a series of observations and excerpts from conversations I had with some of the most interesting people I met.

The PCB Dinosaurs Get New Life at IPC APEX EXPO 2018

04/09/2018 | Dan Feinberg, FeinLine Associates, Inc.
The Order of the PCB Dinosaurs (originally called the PWB Dinosaurs—the sign of a true dino) was born because of a comment almost 20 years ago by my good friend Bernie Kessler. Back in the day, when suppliers like us became IPC members, we could only be associate members; unlike fabricators, we could not serve on the board and we could not lead key committees.



Copyright © 2018 I-Connect007. All rights reserved.