NON-INVASIVE SOLDERABILITY TESTS FOR LEAD–FREE PACKAGING
Authors: Michael Pavlov, Peter Bratin, Eugene Shalyt, Karsten Andrae, Chenting Lin, and Tien Ai Wee Date Published: 1/17/2006
Pan Pacific Symposium
Abstract: The PWB manufacturing industry has been moving towards lead-free finishes. This paper discusses using an electrochemical technique to quantitatively characterize alternative finishes (to HASL), such as OSP, immersion tin, immersion gold, and immersion silver. Analysis results on production samples are presented and the correlation between electrochemical chart features and the film properties, including quality of coatings, uniformity of film across the board, cleanliness of the substrate, solderability and reliability of the layers are discussed. The characteristics established throughout this work can potentially help quality engineers identifying difficult-toobserve product defects in production environments and therefore enhance the smooth transition into lead-free finishes.