As one of the several models to improve the drift - diffusion model , the hydrodynamic model plays an increasingly important role in simulating the behavior of the charge carrier in sub - micron semiconductor devices because it can exhibit velocity overshoot and ballistic effects for which are not accounted the classical drift - diffusion model 漂移扩散模型自上世纪五十年代初一出现,就得到了人们的广泛关注。但随着微电子技术的发展,它不能很好的解释半导体中的有些现象,流体动力学模型就应运而生了。