Analysis of Metal Work-Function Modulation Effect in Reconfigurable Field-Effect Transistor

Abstract

Work-function modulation in a reconfigurable field-effect transistor (RFET) is investigated by 3-D TCAD simulations. A significant work-function dependence is found in the critical electrical performances of RFET. The results show that the ON-state drive current ${I}_{ \mathrm{\scriptscriptstyle ON}}$ is mainly dominated by the control gate (CG) and source work function, while the OFF-state leakage current ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ is dominated by program gate and drain work function. With the work-function regulation, more flexible electrical characteristics among both n- and p-type configurations can be obtained, and an RFET with strict symmetric ON-state current and ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio, that is, ( ${I}_{ \mathrm{\scriptscriptstyle ON}}{)}_{\text {n}}:{(}{I}_{ \mathrm{\scriptscriptstyle ON}}{)}_{\text {p}} = {(}I_{ \mathrm{\scriptscriptstyle OFF}}{)}_{\text {n}}:{(}{I}_{ \mathrm{\scriptscriptstyle OFF}}{)}_{\text {p}} = {1}:{1}$ , has been realized in this work. The underlying physical mechanism is explored, and the corresponding performance of the application in logic and memory is discussed. Moreover, the work-function regulation in CG and source can be recognized as an effective method to subtle tweak noise margin of electrical systems.