  Integrating nanophotonics with electronics promises revolutionary
applications, from LiDAR to holographic displays. Although silicon photonics is
maturing, realizing active nanophotonics in the ubiquitous bulk CMOS processes
remains challenging. We introduce a fabless approach to embed active
nanophotonics in bulk CMOS by co-designing the back-end-of-line metal layers
for optical functionality. Using a 65nm CMOS process, we create plasmonic
liquid crystal modulators with switching speeds 100x faster than commercial
technologies. This zero-change nanophotonics method could equip mass-produced
chips with optical communications, sensing and imaging. Embedding nanophotonics
in the dominant electronics platform democratizes nanofabrication, spawning
technologies from chip-scale LiDAR to holographic light-field displays.
