Characterization of 4H-SiC MOSFET Interface Trap Charge Density Using a First Principles Coulomb Scattering Mobility Model and Device Simulation
Characterization of 4H-SiC MOSFET Interface Trap Charge Density Using a First Principles Coulomb Scattering Mobility Model and Device Simulation
复制标题
使用第一原理库仑散射迁移率模型和器件仿真表征 4H-SiC MOSFET 界面陷阱电荷密度
DOI：
10.1109/sispad.2005.201481
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
A. Lelis
中科院分区：
文献类型：
--
作者：
S. Potbhare;N. Goldsman;G. Pennington;J. McGarrity;A. Lelis
我们开发了一个基于物理的器件模拟器，用于对4H-SiCMOSFET进行详细的数值分析。作为模拟中实现的漂移扩散模型的一部分，建立了SiCMOSFET的第一性原理准二维库仑散射迁移率模型。这个库仑散射迁移率模型考虑了被占据的界面陷阱的散射、固定氧化物电荷的散射、反型层内移动载流子的分布、移动载流子的屏蔽和温度。利用这一迁移率模型表明，库仑散射在界面附近起主导作用。通过比较模拟的I-V曲线和室温下的实验数据，提取了界面陷阱密度的态分布。模拟结果表明，4H碳化硅的界面陷阱态密度在禁带中部很低，而在导带边缘附近很高，严重限制了器件的性能。
We have developed a physics based device simulator for detailed numerical analysis of 4H-SiC MOSFETs. As part of the drift diffusion model implemented in the simulator, a first principles quasi-2D Coulomb scattering mobility model for SiC MOSFETs has been developed. This Coulomb scattering mobility model takes into account scattering by occupied interface traps, scattering by fixed oxide charges, distribution of mobile carriers inside the inversion layer, screening by mobile carriers and temperature. Using this mobility model it has been shown that Coulomb scattering plays a dominant role very close to the interface. The interface trap density of states profile has been extracted by comparing simulated I-V curves to experimental data for room temperature. Simulations show that interface trap density of states is low in the midgap region and very high near the conduction band edge in 4H SiC, and it severely limits device performance.