Effect of Process Parameters on Mode Conversion in Submicron Tapered Silicon Ridge Waveguides

The modal property and light propagation in tapered silicon ridge waveguides with different heights are investigated for a on insulator (SOI) platform 500 nm (Si) thickness. Mode conversion between the transverse magnetic (TM) fundamental higher-order electric (TE) modes occurs when is propagated waveguide taper. Such due to mode hybridization resulting from vertical asymmetry of cross-section waveguides. influence angled sidewalls asymmetric cladding also studied. It shown that very long taper length (adiabatic) required complete take place. Conversely, such could be suppressed by designing short non-adiabatic Our results show significant improvement performance metrics can achieved considering process parameters’ effect conversion. With an optimum selection etching depth accounting asymmetries cladding, we demonstrate 84.7% reduction 97% efficiency TM preserving (ultra-short). analysis essential applications as compact polarizers, polarization splitters/rotators, tapers devices.