一种新型源电极的DMDG隧穿场效应晶体管

A Novel Source Electrode Dual-Material Double-Gate Tunneling Field-Effect Transistor

研究了一种新型源电极的双物质双栅隧穿场效应晶体管（NSE-DMDG-TFET）,该器件结合了新型源电极和双物质栅的优点,其中新型源电极由传统的欧姆接触电极和高功函数浮空肖特基接触电极构成,该肖特基接触电极可有效抬升其电极下的能带、增大源区价带和沟道区导带之间的能带重叠区、减小隧穿距离,提高了开态电流和开关电流比,获得了更小的亚阈值摆幅。运用Silvaco TCAD软件完成器件仿真,并优化了该肖特基接触电极与栅电极的间距、栅金属功函数等参数。仿真结果表明：在室温下,该隧穿场效应晶体管的开态电流为3. 22×10^-6A/μm,关态电流为5. 71×10^-17A/μm,开关电流比可达5. 64×10^10,亚阈值摆幅为34. 22 mV/dec。

A novel source electrode dual-material double-gate tunneling field-effect transistor（ NSEDMDG-TFET） was studied. The proposed device combined advantages of the novel source electrode and the dual-material gate. The novel source electrode was composed of the conventional ohmic contact electrode and the high work function floating Schottky contact electrode. The Schottky contact electrode with higher work function effectively lifts the energy band beneath the Schottky contact electrode,increases the energy band overlap area between the valence band of the source side and the conduction band of the channel side and decreases the tunneling width. Thus,the on-state current and on/off current ratio are improved,and the lower subthreshold swing is obtained. The novel device structure and simulation results were obtained by using Silvaco TCAD software and the parameters were optimized,such as the spacing between the Schottky contact electrode and the gate electrode,and the metal work functions of gate. The simulation results show that the on-state current of the TFET is 3. 22 × 10^-6 A/μm,the off-state current is 5. 71 × 10^-17 A/μm,on/off current ratio is 5. 64 × 10^10 and the subthreshold swing is 34. 22 mV/dec at room temperature.