Hybrid energy harvesting in 3-D IC IoT devices

Three-dimensional integrated circuits are a natural platform for IoT devices. IoT devices exhibit a small footprint, integrate disparate technologies, and require long term sustainability (extremely low power or self powered). A hybrid energy harvesting system within a three-dimensional integrated circuit is proposed in this paper. The harvesting system exploits different types of energy available from the ambient (electromagnetic, solar, thermal, and kinetic). Integration of the hybrid harvesting system onto a three-dimensional platform ensures that each type of harvested energy can be individually optimized. In addition, lower parasitic impedances are exhibited within the three-dimensional structure, leading to improved efficiencies in the energy harvesting process. For an example IoT system, the power requirements are less than 57% of the power delivered to the load.