Abstract

Amongst the available lithography techniques, soft UV-nanoimprint lithography (UV-NIL) offers the lowest patterning cost per wafer and provides additional design freedom for fabricating DFB and DBR laser diodes [1]. We have earlier demonstrated cost-effective UV-NIL-based fabrication of 1.55 µm DFBs with laterally-coupled ridge-waveguide (LC-RWG) surface gratings having a side-mode-suppression-ratio (SMSR) as high as 60 dB [2]. Here we report on the DBR-RWG grating design, the fabrication process, and the output characteristics of tapered DBR lasers made using UV-NIL. To our knowledge this is the first demonstration of DBR lasers fabricated using soft-UV-NIL on wafer-scale. The fabricated DBR lasers exhibited a CW output power as high as 400 mW in single-mode operation at room temperature. Even at maximum output power the SMSR was at least ~45 dB, proving the excellent behavior of the surface gratings.

© 2015 IEEE