介绍了在进入22nm技术节点后MOSFET器件的两个发展方向,即多栅结构和应变硅纳米线结构。首先通过分析特征长度与有效栅极数量的关系,表明多栅结构器件可以有效增强栅极对沟道的控制,抑制短沟道效应,接近理想的亚阈值斜率;然后分析了应变对能带结构的影响,从理论上论述了应变沟道可以显著提高载流子迁移率;最后介绍了悬浮硅纳米线通过热氧化诱导形成应变沟道的方法,并对应力来源进行了分析。纳米结构CMOS晶体管由平面沟道结构向立体沟道结构转变,将成为器件未来主流的发展方向。
Two development directions of the MOSFET device,i.e.the multi-gate structure and strain silicon nanowires structure after the 22 nm node was introduced.Firstly,the relationship analysis of the characteristic length and the effective gate number shows that the multiple-gate structure is an effective way to enhance the controllability of the gate on channels and suppress the short-channel effects,and the subthreshold slope of the multi-gate MOSFET approximates to the ideal value.Then,the effect of the strain on the energy band structure is analyzed,and the improvement of the strain channels on the carrier mobility significantly is discussed theoretically.Finally,the formation method of the strain channels from the suspended silicon nanowire by the thermal oxidation induction is introduced,and the sources of the stress is analyzed.The transformation from the plane channel structure to the stereo channel structure of the nano structure CMOS transistors will be the mainstream development direction of future devices.