Modified Hurkx band-to-band-tunneling model for accurate and robust TCAD simulations

Abstract

Band-to-Band Tunneling (BTBT) is a non-local process and is responsible for some of the major leakage mechanisms in transistors such as Gate Induced Drain Leakage (GIDL). It is therefore important to include BTBT in Technology Computer Aided Design (TCAD) simulations to properly capture the leakage current. However, due to its non-local nature, BTBT simulation is computationally intensive. Local BTBT models such as Hurkx model can reduce the computation burden but often underestimate the leakage current at large bias. A new modified Hurkx BTBT model for homojunction devices is proposed and showed to match non-local BTBT model well in diode leakage and transistor GIDL simulations. Compared to non-local BTBT model, using the modified Hurkx model, the simulation speed is increased by >6 times in a 3D FinFET IDVG simulation with GIDL.