Analytical Modeling for Electrical Characteristics of Source Pocket-Based Hetero Dielectric Gate TFETs

Abstract In this article, a physics-based 2-D analytical model for electrical charateristics such as electric field, surface potential and drain current of source pocket hetero-dielectric double-gate tunnel FET (SP-HD-DG-TFET) is proposed to simultaneously increase the drain current and immune the subthreshold swing (SS). The presented structure of the device consist of source pocket of a highly n + doped Silicon with a horizontally stacked gate-oxide structure of HfO2/SiO2. Poisson's equation has been discussed in the channel region by applying the parabolic approximation technique and appropriate boundary conditions. The expression of electric field has been developed using the channel potential model. Analytically integration of band-to-band tunneling generation rate over the channel thickness yields the drain current expression. The device's performances of SP-HD-DG-TFETs using the suggested model have been found better in terms of V-I characteristics, ION/IOFF, and SS as compared with hetero-diegetic double gate TFET (HD-DG-TFET), high-k TFET and conventional DG-TFET. The suggested model's output has been compared to simulation results produced by the SILVACO ATLAS TCAD tool and found to be good accordance between them.