An improved three-state master equation model for capacitively coupled single-electron transistor

In this paper, we develop an improved semi-classical steady-state model for capacitively coupled single-electron transistor (SET). This SET model is based on the three-state steady-state master equation, but has some revision at different device parameters, and is thus called the improved three-state master equation model. We calculate I/sub DS/-U/sub DD/, I/sub DS/-U/sub G/, and G/sub DS/-U/sub DD/ characteristics for different device parameters. We also present corresponding characteristics calculated by the Monte Carlo method and the full master equation method in most cases. The results demonstrate that the new approach is comparable to the Monte Carlo method and the full master equation method in precision, even in the high voltage region of V/sub DS/, and it simplifies the calculation and improves the speed of numerical simulation. This model can easily be embedded in the SPICE program. Of course, the validity of this embedded model depends on whether the SET can be regarded as a separate component in the circuit.