One of the most serious issues in information industries is the bandwidth bottleneck in inter-chip interconnects. We propose a photonics-electronics convergence system to solve this issue. We fabricated a high density optical interposer to demonstrate the feasibility of the system by using silicon photonics integrated with an arrayed laser diode, an optical splitter, silicon optical modulators, germanium photodetectors, and silicon optical waveguides on a single silicon substrate. Error-free data transmission at 12.5 Gbps and a transmission density of 6.6 Tbps/cm2 were achieved with the optical interposer. We believe this technology will solve the bandwidth bottleneck problem in the future.