On-Chip Integration of Orthogonal Subsystems Enabled by Broadband Twist at 220–325 GHz

In this article, we report for the first time on a low-loss compact platform that enables integration of H-and E-plane rectangular waveguide subsystems enabled by 90 $^{\circ}$ polarization rotation sections silicon-micromachined chip. The proposed offers unprecedented design flexibility 2.5D fabrication technology such as silicon micromachining, since orthogonal device with full freedom in H-plane geometries can be cofabricated geometries, novel, integrated twists optimized fabrication. is developed use broadband millimeter-and submillimeter-wave circuits and prototypes are implemented 220–325-GHz band. A prototype chip demonstrating platform, bonding three stacked chips, fabricated. measured results twist exhibit very low insertion loss less than 0.2 dB return 20 or better most An eighth-degree lowpass filter axial ports having cut-off frequency 280 GHz codesigned transition fabricated to demonstrate its application. shows 0.4-dB has passband 14 dB.