采用有限元方法研究轻掺杂源漏结构对异质栅MOSFET的性能影响(英文)

Analysis of Effect of Lightly Doped Drain and Source Structure on the Hetero-material-gate MOSFET Performances Using Finite Element Method

提出了一种轻掺杂源漏结构结合异质材料双栅结构的MOSFET(简称LDDS-HMG-MOSFET)。使用二维非平衡格林函数(NEGF)对该结构进行仿真,其中非平衡格林函数的计算使用有限元法(FEM)。仿真结果表明,在该新型结构中,异质栅结构能够降低漏电流从而能够有效抑制漏极感应势垒较低效应(DIBL),LDDS结构能够增加有效栅长,有效抑制带带隧穿效应(BTBT)和热电子效应。因此,与传统单材料栅结构的MOSFET(简称C-MOSFET)相比,LDDS-HMG-MOSFET具有更加优越的性能、更低的漏电流和更大的开关电流比(Ion/Ioff)。

A novel device named dual-gate hetero-material-gate MOSFET with lightly doped drain and source （LDDS-HMG-MOSFET） is presented. The proposed structure has been simulated employing twodimensional non-equilibrium Green＇s functions （NEGF）with finite element method （FEM）. The simulation results show that lower leakage current of this device is mostly attributed to the HMG structure which also suppresses drain induction barrier lower （DIBL） effect. Because LDDS structure has longer effective gate length, it can effectively suppress band to band tunneling （BTBT） and the hot electron effect. Hence, compared with conventional single-material-gate MOSFET （C-MOSFET）, LDDS-HMG-MOSFET has su- perior performances, featuring less leakage current and larger ON-OFF ratio （Ion/Ioff）.