Integrating Complex Technologies into Today's SMT Environment

摘要

Taking a look at the topics covered by any of the numerous conferences occurring in the United States annually, one can identify the latest technologies appearing in electronic products. Chip scale packaging (CSP), 0201 passive components, lead-free soldering and optoelectronics are among the top-of-the-list technologies currently being implemented on PCBs or actively being evaluated by companies for near-term use. Never before, for example, have the fundamental physics of solder paste printing been such an issue since having to deal with ultra-small (250μm) apertures as seen with CSPs and 0201s. Board-level optoelectronics assembly, an area of growth in the communications and networking sectors, is a very deli- cate process. Packages typically are expensive and fragile, especially after the leads of the devices have been formed. Design guidelines for these complex technologies also are much different than those of conventional SMT processing because board design plays a more critical role in ensuring assembly yield and product reliability. For example, notable reliability increases can be established by merely changing the board bond-pad size for CSP solder interconnects.