Electronics Forum | Mon Apr 13 23:02:52 EDT 2009 | davef
Use IPC-4552 for your ENIG thickness. Typically, ENIG has nickel deposit with medium [7-9 percent by weight] phosphorus content. That's what fabs do on rigid boards. On a flex with medium-P and IPC-4552 specified ENIG, you could see brittleness and
Electronics Forum | Wed Nov 04 13:15:53 EST 2009 | tstrat
I asked our lab about this and received this response: "Typically 7 - 9wt% phosphorus is used. Higher concentrations (10 - 12 wt% phosphorus) reportedly help prevent Ni-P corrosion during the IG processing step, but they are also reportedly more dif
Technical Library | 2015-11-25 14:15:12.0
In this study various printed circuit board surface finishes were evaluated, including: organic solderability preservative (OSP), plasma finish (PF), immersion silver (IAg), electroless nickel / immersion silver (ENIS), electroless nickel / immersion gold hi-phosphorus (ENIG Hi-P), and electroless nickel / electroless palladium / immersion gold (ENEPIG). To verify the performance of PF as a post-treatment option, it was added to IAg, ENIG Hi-P, and ENEPIG to compare with non-treated. A total of nine groups of PCB were evaluated. Each group contains 30 boards, with the exception on ENIS where only 8 boards were available.
Technical Library | 2023-01-10 20:15:42.0
Over the past years there has been consistent growth in the use of electroless nickel / immersion gold (ENIG) as a final finish. The finish is now frequently being used for PBGA, CSP, QFP and COB and more recently gathered considerable interest as a low cost under-bump metallization for flip chip bumping application. One of the largest users for this finish has been the telecommunication industry, were millions of square meters of PCBs with ENIG have been successfully used. The nickel layer offers advantages such as multiple soldering cycles and hand reworks without copper dissolution being a factor. The nickel also acts as a reinforcement to improve through-hole and blind micro via thermal integrity. In addition the nickel layer offers advantages such as co-planarity, Al-wire bondability and the use as contact surface for keypads or contact switching. Especially those pads, which are not covered by solder need a protective coating in corrosive environment – such as high humidity or pollutant gas.
SMTnet Express, August 9, 2018, Subscribers: 31,244, Companies: 11,011, Users: 25,072 New Phosphorus-based Curing Agents for PWB A. Piotrowski, M. Zhang, S. Levchik - ICL-IP , Y. Zilberman, Eran Gluz - IMI As a result of the continuous
