Propagation Loss Improvement in Ge-on-SOI Mid-Infrared Waveguides Using Rapid Thermal Annealing

摘要

We report on the improvement of propagation loss in Ge-on-SOI waveguides developed for mid-infrared wavelengths. Strip waveguides of varying widths have been developed in 0.85 μm thick Ge core and an improvement of up to ∼3.5 dB/cm has been achieved by annealing the samples at 700 °C for 120 s. The improvement is consistent for both TE and TM polarized light at 3.682 μm . The method is proven feasible for repairing material growth defects and achieving loss performance commensurate with that required for integrated photonics for sensing applications. The minimum propagation loss achieved is ∼10 dB/cm after annealing.