Comparison of quasi-static and non-quasi-static capacitance models for the four-terminal MOSFET

Analytic comparison of quasi-static and non-quasi-static capacitance models is performed for the four-terminal MOSFET with the bulk charge effect included under all operating regimes (weak, moderate, and strong inversion). It is shown that, with the use of a linearized bulk charge density, the Ward quasi-static charge-based approach [2] is equivalent to the non-quasi-static solution [5] in terms of the capacitances calculated at low frequencies. Such a mathematical link between the two approaches may be crucial toward developing high-frequency models for transient analysis.