Abstract
Capillary physics was used to predict the size of solder bumps processed through a heated reflow cycle. Based on the density, surface tension, and volume of the solder material the effects of body forces are negligible compared to surface tension effects. For this case the predicted equilibrium shape of the molten solder is a truncated sphere, where the base of the sphere is defined by the bump input/output (I/O) pad on the integrated circuit (IC). Experiments using different size bumps on Si wafers were conducted to test the validity of the truncated sphere model. The experimental results matched the model to within 11% for the predicted height and 8% for the predicted radius. Using dimensionless variables for the solder volume, bump height, and bump radius allows these results for reflowed height and radius to each be plotted on a single curve and fitted with a single equation. These results can be used to design ICs, solder bumps, and solder bump assemblies in order to ensure that the attached IC can be underfilled reliably, and to ensure reliable products.
Sign-in/Register to access full text options 
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: IEEE Transactions on Components, Packaging, and Manufacturing Technology: Part B
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.
