Charge and Capacitance Compact Model for III-V Quadruple-Gate FETs with Square Geometry

In this work, we propose a physics-based compact model for square geometry gate-all-around quadruple-gate FET (QGFET) structure with a III-V semiconductor channel. The Poisson and the Schrödinger equations are decoupled using an energy perturbation approach. Using the recently proposed constant charge density approximation the potential inside the channel is modeled in a mathematically simple form. Using the approximation further the perturbation term is derived analytically. The model also takes into account the non-iso-potential insulator-semiconductor interface in QGFET. The proposed model is mathematically simple and computationally efficient for implementation in a circuit simulator. The model is validated against the data from a 2D Poisson-Schrödinger solver for QGFETs of different dimension and channel material.