Efficient perfectly vertical grating coupler for multi-core fibers fabricated with 193 nm DUV lithography

• DOI: 10.1364/ol.43.005709
• Publication Date: 2018-11-15T21:14:07Z
• Authors: Yeyu Tong; Wen Zhou; Hon Ki Tsang
• Keywords: 0103 physical sciences; 01 natural sciences; 7. Clean energy

We propose a novel high-efficiency, low-reflection, and fabrication-tolerant perfectly vertical grating coupler (PVGC) with minimum feature size >200 nm to allow for fabrication using 193 deep-ultraviolet lithography. The structural parameters of PVGC were optimized by genetic optimization algorithm. Simulations predicted the coupling efficiency be −2.0 dB (63.0%) back reflections less than −20 in wavelength range 1532–1576 nm. design was fabricated multi-project wafer run silicon photonics, −2.7 (53.7%) 1 bandwidth 33 is experimentally demonstrated. measured reflection −16 over C-band. occupies compact footprint 30 μm×24 μm can interfaced multi-core fibers future space-division-multiplexing networks.