Negative Differential Mobility With Monte Carlo Simulation Method In N-GaAs Material

At present, it is one of the important kinds of modern microwave device that utilizes the principle of negative differential mobility in GaAs material. Thus it is significance to carrying on computer simulation to the Gunn device. In this paper, we will according to Two-energy ban theory putted forward by W·Fawcett, it is supposed that the electron inΓenergy band in conduction band that under electric field and it will arise negative differential mobility when electron transit to X energy band in conduction band after its energy rises. We adopt Monte Carlo particle simulation method to simulate Negative differential mobility in n-GaAs material.Firstly we analysed generation, recombination, scatter and drift of the current carriers. Adopted various kinds of physical assumption, established the model of mobility of carrier, the model of generation-recombination and the model of mobility-diffusion under certain condition. Secondly adopted Monte Carlo particle simulation method, provide the distributing initially with the initial electric field of the particle at first, define the freedom flight time when electrons is accelerated, calculate the scattering type and scattered power, and finally we get various kinds of physical quantities are calculated and tried to get through distributing function in stable state.We get finally the characteristic curve of Negative differential mobility in n-GaAs material, the average drift velocity of electrons vary with temperature, the average drift velocity of electrons vary with flight time.