Performance Improvement of Heterojunction Double Gate TFET with Gaussian Doping

A new Ge/SiGe heterojunction double-gate tunnel field effect transistor (DGT) model with hetero dielectric gate and Gaussian doping drain region is investigated for the first time. The introduction of heterojunction with hetero dielectric will reduce band-to-band tunneling (BTBT) leakage current while maintaining high mobility to enhance drain current and transconductance characteristics of the device significantly. Along with that, the combined effect of analytical drain doping profile (Gaussian) and hetero dielectric suppresses the ambipolar behavior. Different DC characteristics of the device like energy band analysis, electric field, drain current and BTBT generation rate are analyzed for the proposed structure. RF figure of merit for the HD-HJDGT-GD is express by analyzing its transconductance (gm), cut off frequency (fT), maximum oscillation frequency (fmax), gain bandwidth product (GBP) and transconductance frequency product (TFP). The outcome of the model under study is compared with conventional DGT. It is apparent from the analysis that the recommended model has better DC and RF performance, which makes this device worth studying to be used in high-frequency applications. TCAD simulation is performed by using Sentaurus 2D device simulator from Synopsys.