Evaluation of the phase error in Si-wire arrayed-waveguide gratings fabricated by ArF-immersion photolithography

Abstract

The phase errors in 100-GHz spacing, 8-ch, Si-wire arrayed-waveguide gratings (AWG) fabricated by ArF-immersion photolithography were measured by the frequency-domain interference method. To our knowledge, this is the first time phase error measurements in a Si-wire AWG have been performed. By comparing the reconstructed transmission spectrum to the directly measured spectrum, the accuracy of this phase error measurement was confirmed. The average phase error in the AWGs on 6 chips was 0.27π radian, and this value is equivalent to a fluctuation in the effective refractive index of 1.1 × 10^-4.