Fully Inkjet-Printed Ramp Interconnects for Wireless Ka-Band MMIC Devices and Multi-Chip Module Packaging

This work outlines for the first time the development and demonstration of fully inkjet-printed mm-wave 3D ramp interconnects for Ka-band active wireless devices and MCM packaging solutions. Details of the inkjet printing processes are outlined to realize printed RF and DC interconnects for active MMIC dies. Printed ramp interconnects are demonstrated first with an attenuator die to evaluate the multi-material fabrication process, yielding an interconnect insertion loss of approximately 0.45 dB/mm at 24.5 GHz. The process is then applied to a Ka-band LNA MMIC where ramp interconnects for the RF and DC are inkjet-printed, yielding a maximum aggregate gain of 24.2 dB and interconnect insertion loss of approximately 0.57 dB/mm. The fabrication processes and evaluative demonstrations presented in this work highlight the effectiveness of utilizing fully-additive inkjet printing technology for the realization of highly application-specific wireless MCM systems in a low-cost and efficient fashion up to the mm-wave frequency range.