300-Gb/s 24-channel bidirectional Si carrier transceiver Optochip for board-level interconnects

A parallel optical transceiver module with 24-transmitter plus 24-receiver channels has been designed and fabricated. The transceiver Optochip relies on silicon carrier technology to provide a high level of integration of the electrical and optical components onto a single substrate with high density interconnection. The transceiver Optochip consists of the Si carrier platform with 4 flip-chip attached components: two 24-channel 850 nm optoelectronic arrays (VCSELs and photodiodes) and two 24-channel CMOS ICs (receivers and laser drivers). Furthermore, 150-mum diameter "optical vias" are incorporated in the Si carrier at 48 locations of the VCSEL and PD array element in order to allow optical transmission through the silicon carrier. A lens arrays aligned to the optical vias can also be integrated into the Si carrier to collimate the optical inputs/outputs and facilitate optical coupling to/from the Optochip. Complete Optochips have been assembled and fully characterized using optical coupling into multimode fiber (MMF) with all channels fully operational. The 24 transmitter channels showed good performance up to 15 Gb/s with uniform, high optical output power and low jitter. The 24 receiver channels, characterized as full Tx-to-Rx Optochip links, operated error-free up to 12.5 Gb/s. At 12.5 Gb/s, each complete link consumes only 11 mW/Gb/s. The Optochip achieves a 300 Gb/s bidirectional data rate, a new record for parallel optical transceivers.