Abstract
The wettability between solder and substrate is a very important issue in reliability of soldering process. The contact angle θ is used to measure the degree of wetting. The contact angle of lead-free alloy Sn-3 % Ag-0.5 % Cu (wt%) was measured, as a function of temperature, for three different commercial surface finish substrates used in printed circuit boards (PCB): Sn, NiAu and Organic Solderability Preservative (OSP). The measurements were performed by the sessile drop method in two different atmospheres: high vacuum and inert gas. In high vacuum the results showed that on substrates of NiAu and OSP the solder started spreading suddenly at 225 °C and in Sn substrate the contact angle decreases slightly with temperature. In inert gas atmosphere the results showed different behaviours: the contact angle between molten solder in OSP and NiAu substrates is sensitive to temperature; and, in Sn substrate, the contact angle does not change with temperature. The NiAu and OSP substrates showed a better degree of wettability than Sn substrate, in inert atmosphere.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Materials Science: Materials in Electronics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
