Benchmarking and Demonstration of Low-Loss Fused-Silica Stitch-Chips With Compressible Microinterconnects for RF/mm-Wave Chiplet-Based Modules

A fused-silica stitch-chip technology is proposed for RF/mm-wave multichiplet modules where commercial off-the-shelf (COTS) chiplets are densely integrated. Stitch-chip design, RF characterization, and benchmarking to state-of-the-art are presented in this letter. An optimized 500-
$\mu \text{m}$
long stitch-chip channel is measured to have < 0.66 dB insertion loss (IL) and >11.34 dB return loss (RL) up to 50 GHz. The proposed stitch-chip technology features module scalability, low-loss, impedance-matching, and reworkability. The stitch-chip technology can be a potential integration solution for RF/mm-wave front-end modules.