A Chip-First Approach to Millimeter-Wave Circuit Packaging

In this letter, we demonstrate a fully additively manufactured packaging solution for the integration of millimeterwave (mm-wave) devices. This technique employs a chip-first approach to packaging, where die and other components are positioned and a package and interconnects are subsequently built up. This letter allows for the dense populations of components even when they do not share a common vertical height. To demonstrate this concept, we present the fabrication and measurement of two packaged 0-dB attenuators to characterize the performance of the interconnect strategy. These interconnects achieve a worst case loss of 0.290 dB at 40 GHz. Beyond the rated operating range of the device, which is from dc to 43.5 GHz, the interconnects achieve a worst case loss of 0.490 dB at 60 GHz. The approach that we present provides a flexible mm-wave capable and broadband packaging solution that enables the next-generation system-in-package technology.