耗尽型4H-SiC埋沟MOSFET器件解析模型研究  

Study on Analytical Model for 4H-SiC Depletion Buried-Channel MOSFET

作　　者：王巍[1] 秘俊杰[1] 曾勇[1] 王晓磊[1] 唐政维[1] 彭能[1] 

机构地区：[1]重庆邮电大学光电工程学院,重庆400065

出　　处：《微电子学》2010年第2期283-286,290,共5页Microelectronics

基　　金：重庆市自然科学基金资助项目(2006BB2364)

摘　　要：建立了基于漂移扩散理论的4H-SiC埋沟MOSFET器件的物理解析模型。SiC/SiO_2界面处的界面态密度及各种散射机制都会导致器件载流子迁移率的下降,采用平均迁移率模型,分析散射机制对载流子迁移率的影响,讨论了界面态对阈值电压的影响。考虑到器件处在不同工作模式下,沟道电容会随栅压的变化而改变,采用了平均电容概念。器件仿真结果表明:界面态的存在导致漏极电流减小;采用平均迁移率模型得到的计算结果与实验测试结果较为一致。A physical model for 4H-SiC buried channel MOSFET was proposed based on drift-diffusion theory. SiC/SiO2 interface state density and scattering mechanism may cause carrier mobility degradation. By applying average mobility model, effects of scattering mechanism on carrier mobility were analyzed, and the influence of interface state on threshold voltage was discussed. As channel capacitor varies with gate voltages in different operation mode, the average capacitor was employed to characterize the capacitor in various models. It has been shown that the presence of interface state led to a decrease in drain current. Results from simulation with average mobility analytical model are identical with those from measurement.

关 键 词：SIC 埋沟MOSFET 界面态 平均迁移率 

分 类 号：TN432[电子电信—微电子学与固体电子学]