Analytical expression of the three-dimensional potential distribution of a SOI four-gate transistor

An analytical model is developed to determine the 3-D potential distribution of a fully-depleted silicon-on-insulator (SOI) four-gate transistor (G⁴-FET). The potential variations along the channel and between the junction-gates are assumed to be parabolic due to short channel effect and presence of MOS gates. Using these assumptions and with necessary boundary conditions, the 3-D Poisson´s equation is solved to formulate the overall expression. The proposed model successfully correlates the four gates of the device and shows excellent agreement with the charge variation along the channel. Slight modification also agrees with the surface potential of a DGFET.