Development of quasi half coax lines for wafer level packaging

A 50 ohm micromachined interconnect is designed, fabricated, and measured as a broadband interconnect that is compatible with the standard thickness of wafers. It is developed in two applications: a transition from a commercially available 1 mm connector launch assembly to wafer based systems and an interconnect within wafer level designs. S-parameter measured data is shown for coaxially launched structures up to 35 GHz and for probed launched structures up to 50 GHz. The on-wafer probe launched interconnect exhibits less than 1. 1 dB/cm of attenuation at 50 GHz, reflections less than 15 dB across 50 GHz, and 2.5 times less dispersion than a planar microstrip with comparable dimensions.