An analytic model for asymmetric trapezoidal-gate MOSFET

The innovative asymmetric trapezoidal gate (ATG) structure has a relatively narrow drain-side width as compared to the source-side width, giving the trapezoidal shape of ATG MOSFETs. In this paper, an analytic model including the DC drain current and AC dynamic capacitance is demonstrated. The DC linear/saturation drain current has been derived by Poisson's equation, with Green's function method. The subthreshold current is also deduced by Poisson's equation, with the polynomial function as our main strategy. On the AC dynamic capacitance, we follow Ward and Dutton's channel charge scheme to partition Q/sub D/ and Q/sub S/, thus all the capacitance can be obtained. Above all, in comparisons with the simulation results, our model is in good agreement with the measurement data. Besides, our model provides an effective and economic way to describe the characteristics of the ATG devices.