On-wafer level packaging of RF MEMS devices for Ka-band applications

In this paper, on-wafer level packaging technology for RF MEMS is described, and then a novel packaging design for RF MEMS devices with different fabrication technology at millimeter-wave band is presented. The discussed RF MEMS devices on naked wafer includes a MEMS filter and a distributed MEMS transmission line (DMTL) phase shifter, which are fabricated using LIGA and micromachined technology, respectively. In order to realize the integration of those devices into a system at millimeter wave band, the packaged devices are embedded in a substrate. After incorporating the parasitic parameters into the equivalent circuit for the phase shifter, it is found that the bandwidth of predicted packaging increases about 8 GHz, moreover, the predicted packaging area is only about 40% larger than the naked device.