高k栅栈MOSFET共振隧穿模型

针对高介电常数（k）栅堆栈金属氧化物场效应晶体管（Metal-Oxide-Semiconductor Field-Effect Transistor,MOSFET）实际结构,建立了入射电子与界面缺陷共振高k栅栈结构共振隧穿模型.通过薛定谔方程和泊松方程求SiO2和高k界面束缚态波函数,利用横向共振法到共振本征态,采用量子力转移矩阵法求共振隧穿系数,模拟到栅隧穿电流密度与文献中实验结果一致.讨论了高k栅几种介质材料和栅电极材料及其界面层（IL）厚度、高k层（HK）厚度对共振隧穿系数影响.结果表明,随着HfO2和Al2O3厚度减小,栅栈结构共振隧穿系数减小,共振峰减少.随着La2O3厚度减小,共振峰减少,共振隧穿系数却增大.随着SiO2厚度增大,HfO2,Al2O3和La2O3基栅栈结构共振隧穿系数都减小,共振峰都减少.TiN栅电极HfO2,Al2O3和La2O3基栅栈比相应多晶硅栅电极栅栈结构共振隧穿系数小很多,共振峰少.

Resonant tunneling model of high-k gate stack for MOSFET

Based on the actually structure of high-k gate stack MOSFET device, a resonant tunneling model of the high-k gate stack structure was development. Obtained wave function of bound states between SiO2 and high-k interface through the schrodinger equation and poisson equations .Got resonance eigen state by using transverse resonance method, and the resonance tunneling coefficient by using the transfer matrix method. Simulated result of gate tunneling current density is agree well with the experimental results in literature. The influence of high-k gate various materials, gate electrode materials, interface layer thickness and high-k layer thickness on the resonance tunneling coefficient is discussed. The results show that, with the decreasing thickness of the HfO2 and A1203, the resonant tunneling coefficient of gate stack structure decreases, and their resonance peak reduce. With the decreasing thickness of La203, resonant tunneling coefficient increases, and it＇s resonance peak reduction. With the increasing thickness of SiO2, the resonant tunneling coefficient of HfO2, A1203, and La203-based gate stack structure decrease, and their resonance peaks are reduce, the resonant tunneling coefficient of HfO2, A1203 and La203-based gate stack with TiN gate electrode is much smaller than the corresponding gate stack structure with polysilicon gate electrode, and less resonance peak.