AUSN solder vacuum packaging using melted solder floodgates and laser-activated non-evaporable getters for SIC diaphragm anticorrosive vacuum sensors

Versatile wafer-level vacuum packaging technology using screen-printed AuSn eutectic solder was developed and applied to a SiC diaphragm anticorrosive vacuum sensor. Thin film Ti/SiO₂ ¿floodgates¿ were used to prevent melted AuSn solder from flowing into microstructures, e.g. capacitive gaps. After vacuum packaging, a non-evaporable getter (NEG), which chemically absorbs residual gas, was activated by Nd:YAG laser. In comparison to other wafer-level vacuum packaging technologies, the developed one establishes electrical connections and feedthroughs simultaneously, and is tolerant to surface roughness, surface contamination and wafer waviness.