GaN n-MOSFET反型沟道电子迁移率模型

在器件物理的基础上,提出了一种半经验的GaN n-MOSFET反型沟道电子迁移率模型.该模型考虑了位错、界面态、光学声子、离化杂质、表面粗糙、声学声子,以及高场对迁移率的影响.模拟结果表明,界面态和位错是影响沟道迁移率的主要因素,尤其是界面态,它决定了迁移率的最大值,而位错密度的增加使迁移率减小.此外,表面粗糙散射和高场散射主要影响高场下载流子迁移率.由此可见,GaN n-MOSFET沟道迁移率的提高依赖于晶体质量和界面质量的提高.

Modeling of Inversion Channel Electron Mobility for GaN n-MOSFET's

A model for inversion channel electron mobility of GaN n-MOSFET's is proposed based on semiconductor device physics.Effects of interface states,ionized impurities,optical phonon,surface roughness,acoustic phonon,dislocation scatterings and high fields on the mobility are considered in this model.Simulation results indicate that the interface states and dislocation are major factors affecting channel electron mobility,and the maximum mobility depends on interface states.Furthermore,surface-roughness scattering and high-field scattering mainly affect the carrier mobility at high fields.Therefore,it can be concluded that the channel mobility of GaN n-MOSFET's could be increased by decreasing the interface-state density and improving the epi-layer quality.