The impact of technology on power for high-speed electrical and optical interconnects

The impact of technology scaling - in the form of transistor performance improvement and a higher demand in bit rate - on power dissipation of short distance electrical and optical interconnects is extensively quantified. We find that: 1) the transistor performance improvement has a similar impact on both types of interconnects, leaving critical length (length above which optical interconnects dissipate lower power) relatively unchanged; 2) the increase in bit rate significantly reduces critical length, favoring optics; 3) at the 32 nm technology node (and beyond) with its commensurate bandwidth requirement, optical interconnect becomes favorable for distances as low as 10 cm corresponding to inter-chip communication; 4) most critical factors in making optical interconnects favorable are reduction in coupling losses and optical detector capacitance.