Heterogeneously integrated sub-40nm low-power epi-like Ge/Si monolithic 3D-IC with stacked SiGeC ambient light harvester

Abstract

For the first time, we report heterogeneously integrated sub-40nm epi-like Ge/Si monolithic 3D-IC with low-power logic/NVM circuits and efficient photovoltaic energy harvester. Threshold voltage engineering and driving current boosting technologies enable stackable Ge/Si UTB (<15nm) MOSFETs, CMOS inverter and SRAM (SNM=270mV@0.7V) achieve low operation voltage. Stackable 1-T NVM with high speed (100ns) and low driving-voltage operation provide power-off storage while SRAM serve as power-on working memory. 100% aperture ratio SiGeC ambient light energy harvester with maximum output power of 7mW/cm2 layered on the monolithic 3D-IC chip envisions a self-powered monolithic 3D-IC technology for advanced low-power wire-less sensor networks, wearable devices, and devices for Internet of Things.