Energy scavenging and storage using through silicon vias to reduce power consumption in 3D ICs
Through silicon vias (TSV) are an enabler for high performance Three Dimensional Integrated Circuits (3DIC). TSVs are used for signal, power and ground lines in 3DICs. TSVs used to carry signals can induce noise in nearby circuitry and in those instances shielding is required. Traditional shielding is composed of guard rings surrounding the signal TSVs or if the signal is differential in nature, a careful arrangement of TSVs carrying the differential signals can aid in noise reduction. In the guard ring scenario, the guard rings are typically tied to ground. This paper proposes a technique for energy scavenging utilizing the guard rings for shielding TSVs. Energy absorbed by the guard rings can be stored for later use by the system. This paper examines the feasibility of configuring the guard rings to charge a decoupling capacitor instead of shunting energy to ground. It is shown that the decoupling capacitor can be charged using this method and that under certain conditions, the overall power of the system can be reduced by 4% to 15%.