A Physics-Based Compact Model for the Static Drain Current in Heterojunction Barrier CNTFETs-Part I: Barrier-Related Current

A physics-based compact analytical formulation for the static drain current in heterojunction barrier (HB) carbon nanotube field-effect transistors is derived by incorporating the tunneling current through the barriers. This enables to capture the distinct curve shapes of device characteristics as compared to devices without HBs. For solving the Landauer integral a Gaussian-shaped surrogate function for the energy-dependent integrand is utilized. Moreover, the impact of multiple reflections between source and drain barrier is accounted for. The new formulation includes a smooth transition from thermionic emission-based transport in the subthreshold region to tunneling-dominated transport in the above-threshold regime.