Development of copper μbumps based flip chip assembly for heterogeneous photonic integration

Heterogeneous integration of photonic devices with electronic Integrated Circuits (IC) or microlenses is increasing rapidly and moves from prototyping to mass volume manufacturing. One of the key process for this integration is the hybridization of the photonic device with the other component. Based on the choice of using electrochemically deposited lead free solder copper pillars, this paper will describe the development and comparison of two different flip chip processes, thermo-compression and mass reflow, with regard to the constrains and specifications of different integration schemes developed for Lidar or telecom applications. The final choice for each will be based on the compromise between assembly robustness and high throughput for manufacturing.