Multichannel ultrathin silicon-on-sapphire optical interconnects

Multichannel optical interconnects were developed using vertical-cavity surface-emitting laser (VCSEL) arrays and metal-semiconductor-metal photodetector (PD) arrays and driven by complementary metal-oxide-semiconductor circuits that were fabricated using ultrathin silicon-on-sapphire (SOS) technology. Low-threshold oxide-confined top-emitting VCSEL 8 x 8 arrays were designed and fabricated with off-site contact bonding pads. The arrays were flip-chip bonded to driver arrays on sapphire substrates and mounted on high-speed printed-circuit boards as optical transmitter arrays. The laser output was transmitted through the transparent sapphire substrate and coupled to MSM PD arrays and the SOS receiver. This optical interconnect system was demonstrated to operate at a data rate of 1.0 Gb/s per channel with a power consumption of 28 mW for each channel including transmitter and receiver.