Next-Generation Lead-Free Solder Plating Products for High Speed Bumping, Capping and Micro-Capping Applications

Flip-chip interconnect and 3-D packaging applications must utilize reliable lead-free solder joints in order to produce highly efficient, advanced microelectronic devices. The solder alloy most commonly utilized for these applications is SnAg, which is typically deposited by electroplating due to lower cost and greater reliability as compared to other methods. The electroplating performance and robustness of SnAg products for bumping and capping applications is highly dependent on the organic additives used in the process. Here, next-generation SnAg products that improve the rate of solder electrodeposition without compromising key requirements such as tight Ag% control, uniform height distribution and smooth surface morphology will be discussed. These plated solders were then evaluated for compatibility with bumping, capping and micro-capping applications.