Technology scaling behavior of optimum reverse body bias for standby leakage power reduction in CMOS IC's

Abstract

We demonstrate that, there is an optimum reverse body bias, unique to any technology generation, that minimizes the standby leakage power consumption of an IC design implemented in that technology. We also show: (1) the optimum reverse body bias value reduces by -2X per technology generation, and (2) the maximum achievable leakage power reduction by reverse body biasing diminishes by -4X per generation under constant field technology scaling scenario. Optimum point occurs as a result of reduction in subthreshold leakage and an increase in junction band-to-band tunneling leakage with applied reverse bias. Therefore, new junction engineering techniques to reduce the bulk band-toband tunneling leakage current component across the junction are needed to preserve the effectiveness of reverse body biasing for standby leakage control in future technologies.