Design, fabrication, and measurement of benzocyclobutene polymer zero-level packaging for millimeter-wave applications

This paper presents a whole benzocyclobutene (BCB) membrane zero-level packaging using a wafer-level BCB bonding technique and a membrane transfer technique with silicon carrier wafers for millimeter-wave devices. The developed packaging technology has been applied to a coplanar line and thin-film planar resonator to evaluate the effect of the packaging on their RF performance. The packaged coplanar line has shown an insertion loss change less than 0.01 dB/mm from dc to 110 GHz and thin-film resonator has 0.6-dB return loss change at 62.5-GHz resonant frequency after packaging. In addition, a flip-chip compatible BCB packaging technology has been implemented using gold-electroplating technology for a vertical interconnection. The effects of a vertical interconnection on the coplanar line and a BCB layer over the gold-plugged coplanar line have also been investigated.