Ultra-broadband Integrated Capacitive Silicon Interposer assembled with SnBi Eutectic Solder

Low temperature solders usage for broadband assemblies represent an important challenge for the industry. Using lower temperatures for reflow subsequently shows less deformation on mother boards used for optical sub-assemblies and then less RF parasitics. However, some parts in optical sub-assemblies, like laser diodes, require good thermal dissipation to work properly and avoid unwanted modulations. This work will present an innovative way to use SnBi (Tin-Bismuth) eutectic alloy to assemble an integrated capacitive Silicon interposer on top of which a laser diode can be assembled as well.