Computational technique for probing terminal control mechanisms inside three-dimensional nano-scale MOSFET

A novel computational technique is presented to study the terminal influence inside the three-dimensional (3D) nano-scale metal-oxide semiconductor field effect transistor (MOSFET) using TCAD simulations. Within the MOSFET the derivative of the electrostatic potential with respect to voltages at each terminal is taken, and when these derivatives are summed together they always sum to unity. It is found that these functions can be used to quantify the relative influence or control of the terminals anywhere inside the MOSFET, including the channel. The motivation for moving from planar MOSFETs to 3D-MOSFETs is to increase the gate control over the channel. The terminal influence functions quantify the notion of control. To gain insight into the working of a semiconductor device, different quantities like potential, charge or current density etc. may be visualised. These quantities are available in the standard TCAD tool-kit. However, these do not directly address the mechanism of terminal control. The terminal response or control functions can be used to do this very clearly.