An active, high bandwidth, flexible connector for large area computational systems

Large area computational systems such as systems-on-wafer (SoWs) require high bandwidth communication links to the outside world. Commercial high bandwidth cabling solutions are incompatible with integration to SoWs due to large plastic connector interfaces. FlexCon, a flexible, high bandwidth connector cable platform, features high density interconnects on a highly flexible, elastomeric substrate integrable with SoWs via conventional reflow processes. However, losses in FlexCon channels limit the maximum reach of FlexCon. Here, we demonstrate two methods of improving the reach of FlexCon. First, the lossy SU-8 dielectric is replaced with a low-loss parylene-N dielectric, reducing losses by 32%. Second, an active linear redriver was implemented on FlexCon via a surface mount assembly process. Process development of direct integration of the linear redriver in the FlexCon substrate is discussed. Additionally, the reliability of FlexCon channels under cyclic mechanical bending is investigated. Changes in insertion loss after 1000 cycles at a bending radius of 2.5mm was found to be <6% at high frequency.