Expert Session »Passive vs. Active Alignment - Strategies in Photonic Assembly«

Our Expert for this Topic: Dr. Gunnar Böttger

Optical coupling in photonic assemblies is commonly realized using active alignment of components such as laser and photo diodes, photonic or quantum chips, optical lenses and fibers: This requires active operation of light sources integrated in chips or system assemblies, to maximize optical coupling in sequential optical alignment and mounting processes (commonly by gluing with optical adhesives and epoxies).

Using glass optical interposers, benches, and even fully packaged systems-in-packages SiP enables new ways in assembly: visual and even passive alignment. 

Visual alignment of photonic assemblies is enabled by using the transparency of glass – giving not only better access and ways for inspection by machine vision, but also minimizing shading for UV-light used for gluing processes.

Furthermore, glass can be very accurately laser structured, either directly or using combined processes such as selective laser etching SLE, yielding µm 3D accurate glass holder, adaptors or even benches: This way a simple insertion of components, not requiring additional fine alignment steps, becomes feasible. Gluing only secures components, with minimal or even eliminated glue gaps.