High‐frequency mobility‐noise temperature

The purpose of that paper is to compute the noise temperature through the Boltzmann and Einstein equations. Using the scattered packet method, described in Ref. 1, we can solve the Boltzmann equation and compute the diffusion coefficient when an electric field is applied. In order to obtain the noise temperature it is then necessary to know the differential (a.c.) mobility of the carriers. At low frequency we can calculate the slope of the velocity field characteristic but this method is not enough accurate at low frequency and even not valid at all at high frequency. We have developed a program enabling us to solve the small signal Boltzmann equation and to obtain the a.c. mobility.