Chip-to-chip optical interconnect using direct optical wire bonding

We present inter-chip optical link based on direct optical wire (DOW) bonding technology fabricated by meniscus-guided polymerization in open-air. The arch shape DOW structure is formed in a single procedure for directly linking silicon photonic chips, where grating couplers are integrated to out-couple guided optical modes. Although a typical grating coupler is employed, the inter-chip DOW link supports a low insertion loss of 6 dB in total with a wavelength-insensitive operation in the measured wavelength range of 1520 nm to 1590 nm. The half-arch shape DOW for linking chip-to-fiber is also shown to verify the feasibility of hybrid integration with edge coupling devices. DOW bonding technology can provide a convenient route to enable direct optical link capable of agile and high-throughput manufacturing for inter-chip optical interconnection.