A Novel Step-Channel TFET for Better Subthreshold Swing and Improved Analog/RF Characteristics

In this paper, a novel device structure is introduced to enhance ON-state current, reduce ambipolar behaviour and better subthreshold swing which is named as step channel tunnel FETs (SC-TFET). This device use small dielectric thickness at source-channel junction to improve device performance. Subthreshold Swing of device is improved due to reduced dielectric thickness at source-channel junction and ambipolar current of device is suppressed by using large dielectric thickness at drainchannel junction. For further improvement of ON-state current high-k dielectric material is introduced as oxide layer which is named as High-K SC-TFET. To analyses device performance characteristics various parameters has been calculated such as parasitic capacitance, transconductance (gm), output transconductance (gds) and cut-off frequency (fT). Finally, a study between conventional TFET, SC-TFET and High-K SC-TFET has been investigated which shows its significant contribution in analog and RF parameters. All the simulations of purpose device have been done using TCAD device simulator.