The Research Of Transistor's Modeling Technology

This paper mainly discusses the method of transistor modeling and the expression of non-linearity. The purpose is to establish a simulated platform of GaAs FET in computer for calculating the non- linearity of non- linear circuit (especially GaAs FET).The non- linearity of circuit is known for a long time, and can be expressed in many ways. After the traditional expression is concluded, a new expression of non-linear Scatter Function is presented, and it's character being discussed.The extraction of parameter of GaAsFET in small-signal is discussed, And the already existed method of modeling of GaAsFET in small-signal is concluded. In the process of modeling in small-signal state, a new method to calculate S-parameters of a complex network is presented, and it's easy to get the S-parameters of complex network by this method. At last, the model of GaAsFET in small-signal is successfully established. This paper also introduces methods to model GaAs FET in large-signal state. Based on the model of GaAsFET in small-signal, the non-linear model of GaAsFET in large-signal is successfully established by measuring GaAsFET in the way of pulse current and calculating non-linear character of GaAsFET. And there is a new modified model in large-signal in this paper. This model is more accurate than anyone else. It's very useful to analyse non-linearity of transistor in large-signal. Next, we will analyse this model with harmonic balance method in order to verify non-linear Scatter Function.