Technology for the Heterointegration of InP DHBT Chiplets on a SiGe BiCMOS Chip for mm-wave MMICs

We present a low-temperature flip-chip-based mounting technology, enabling integration of indium phosphide (InP)-based chiplets on BiCMOS. The process temperatures of well below 200 degrees C allow to mount chips with limited temperature budget without degrading the device performance. To ensure good scalability, repeatability and flexibility in terms of complex transitions we use a pillar-based approach instead of the popular bump array technique. Thermal simulations prove that the increase in thermal resistances due to integration is not critical. The RF performance was evaluated using simple coplanar waveguide (CPW) test chips and carriers without any special transition optimization. The results indicate good broadband characteristics up to frequencies beyond 100 GHz.