The Optimizations of Dual-Threshold Independent-Gate FinFETs and Low-Power Circuit Designs

Abstract

In this paper, a method of optimizing dual-threshold independent-gate FinFET devices is discussed, and the optimal circuit design is carried out by using these optimized devices. Dual-threshold independent-gate FinFETs include low threshold devices and high threshold devices. The low threshold device is equivalent to two merging parallel short-gate devices and high threshold device is equivalent to two merging series SG devices. We optimize the device mainly by selecting the appropriate gate work function, gate oxide thickness, silicon body thickness and so on. Our optimization is based on the Berkeley BSIMIMG model and verified by TCAD tool. Based on these optimized devices, we designed the compact basic logic gates and two new compact D-type flip-flops. Additionally, we developed a circuit synthesis method based on Binary Decision Diagram (BDD) and the optimized compact basic logic gates. Hspice simulations show that the circuits using the proposed dual-threshold IG FinFETs have better performance than the circuits directly using the short-gate devices.