A novel fabrication approach for an athermal arrayed-waveguide grating

A novel method for fabricating an athermal AWG is proposed, using a unique apparatus for ITU-T center wavelength adjustment and optical coupling of two cut-parts. UV adhesive or sticky gel is applied into the gap between the cut-elements and the alignment base substrate by capillary infiltration. The spectrum profiles are almost the same as those of the original chip state, and no deterioration is observed resulting from athermalization. Flat-top athermal AWG modules of 100 GHz x 40 ch are fabricated. Over a temperature range of -40 to 85 degrees C, the center wavelength shift is +/- 22 pm, and the insertion loss change is less than +/- 0.11 dB.