Design of a 32nm Independently-Double-Gated FlexFET SOI Transistor

Considerable recent research has focused on developing vertical FinFET-type double-gated CMOS devices. Planar independently-double-gated FlexFET CMOS transistors have recently been reported, exhibiting strong dynamic threshold voltage control. The FlexFET device design utilizes a mid-gap metal top gate self-aligned to an implanted HET bottom gate. A simple analytical dynamic threshold model is developed in this work and verified by extensive device simulation. Optimization of the top gate oxide thickness, silicon thickness, and gate work functions for a 32nm node FlexFET CMOS technology is achieved by device simulation using SILVACO. Ideal dynamic threshold control of this 32nm device is achieved with relatively thick 11 nm silicon and 4nm gate oxide thicknesses.