Millimeter-wave coplanar interconnects and radiators on FR-4 laminates

Abstract

This paper demonstrates coplanar waveguide (CPW) interconnects and radiators for antenna-in-package (AiP) solutions at millimeter-wave frequencies using flame-resistant 4 (FR-4) laminates. CPW transmission lines and broadband antennas with CPW feeds have been fabricated on two types of FR-4 laminates to detail the performance of this material. Measurements show an average attenuation of 0.19 dB/mm at 60 GHz, which is comparable to that of other packaging substrates at millimeter wavelengths. CPW-fed bow-tie apertures have a return loss below 10 dB from 60 GHz to 90 GHz.