Monte-carlo Simulation On Four-valley Model Wurtzite ZnO

As one of the most promising wide-band-gap semiconductor materials in optic, electric and photoelectric fields, ZnO has attracted much attention these years. The Monte-Carlo method, which is often used in novel device simulations due to its accuracy and intuition, provides a useful tool for the analysis, and understanding of semiconductor devices.This article simulated the electron transport properties in ZnO by the Monte-Carlo method.A four-valley model of the band structure is assumed, and the ionized impurity, polar optical phonon, acoustic phonon, piezoelectric, and intervalley scattering mechanisms are considered. Nonparabolicity is considered in four valleys. We found that optical and intervalley scatterings are dominant in all the scattering mechanism under 300K. Meanwhile, the "blue shift" phenomenon could be observed in electron energy distribution accompanied with the temperature increase. And the drift velocity of electron reached its peak when the applied electric fields reached 500kV/cm, corresponding to the negative differential mobility effect observed in the experiment. At last, we got the electron mobility under room temperature which is about 600cm~2/Vs.Additionally,we also did some improvement on the method through our practical calculation.