One of the most serious challenges facing exponential performance growth in the information industry is the bandwidth bottleneck in interchip interconnects. We propose a photonics–electronics convergence system in response to this issue. To demonstrate the feasibility of the system, we fabricated a silicon optical interposer integrated with arrayed laser diodes, spot-size converters, optical splitters, optical modulators, photodetectors, and optical waveguides on a single silicon substrate. Using this system, 20 Gbps error-free data links and a 30 Tbps/cm2 bandwidth density were achieved. This bandwidth density is sufficient to meet the interchip interconnect requirements for the late 2010s.