Passively aligned multichannel fiber-pigtailing of planar integrated optical waveguides

Abstract

Abstract. A silicon device to simplify the coupling of multiple single-mode fibers to embedded single-mode waveguides has been developed. The silicon device features alignment structures that enable a passive alignment of fibers to integrated waveguides. For passive alignment, precisely machined V-grooves on a silicon device are used and the planar lightwave circuit board features high-precision structures acting as a mechanical stop. The approach has been tested for up to eight fiber-to-waveguide connections. The alignment approach, the design, and the fabrication of the silicon device as well as the assembly process are presented. The characterization of the fiber-to-waveguide link reveals total coupling losses of (0.45 AE 0.20 dB) per coupling interface, which is significantly lower than the values reported in earlier works. Subsequent climate tests reveal that the coupling losses remain stable during thermal cycling but increases significantly during an 85°C/85 Rh-test. All applied fabrication and bonding steps have been performed using standard MOEMS fabrication and packaging processes.

Optically Synchronized Phased Arrays in CMOS

“…For comparatively small systems that require large arrays, electro-optical printed circuit boards (EOCBs) with pick-and-place-compatible mirror elements can be mass-produced on standard or flexible substrates [38], [39]. This is less costly than aligning fibers to every RFIC, since individual fibers or fiber arrays can be passively aligned to the edge of the board using proven techniques [40]. For either large or small systems, the option of OTS through free space, when attenuation is low, eliminates the need for a physical connection.…”