A noncharge-sheet channel potential and drain current model for dynamic-depletion silicon-on-insulator metal-oxide-semiconductor field-effect transistors

摘要

This paper presents a noncharge-sheet channel potential and drain current model for long-channel dynamic-depletion (DD) silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistors (MOSFETs). Based on the Poisson-Boltzmann equation, an analytical solution of the channel potentials in the front, back silicon/oxide and substrate/oxide interfaces is developed. It is a Universal solution which predicts the channel potential accurately in all cases from accumulation to strong inversion. A unified noncharge-sheet drain current expression is derived from the three-interface analysis based on the universal channel potential solution. The proposed model shows excellent agreements with two-dimensional numerical simulations with varying geometrical structures at different device operation regions. This model provides a useful tool to study the device physics and develop a complete compact model for DD SOI MOSFET.