This document describes the features and advantages of Wafer level chip scale packaging (WLCSP) technology, as well as manufacturing process optimization recommendations for Fairchild Semiconductor WLCSP components.
This document serves as an application note intended to provide a recommended starting point for manufacturing process optimization using Fairchild Semiconductor WLCSP components. It addresses critical factors such as board mounting, pad design, and solder joint reliability.
| Peak Reflow Temperature | 260°C |
|---|---|
| Recommended Solder Alloy | SAC 305 |
| Recommended Pad Diameter | 250um |
| Recommended OSP Finish | Enthone® Entek® Plus HT |
Fairchild Semiconductor recommends a pad diameter of 250um for 300um bumps to reduce stress at the die-bump interface.
The lead free alloy SAC 305 (96.5 Sn/3.0Ag/0.5Cu) is recommended as the choice for the electronics industry.
No, it is recommended that the component not be reused if rework becomes necessary due to high temperatures associated with lead free reflow.