Experimental study on uniaxially stressed Gate-All-Around silicon nanowires nMOSFETs on (110) silicon-on-insulator

摘要

Nanowire (NW) MOSFETs, as one promising candidate for future VLSI, have attracted much more attention. Stress engineering is one effective method to improve the channel drive current and has been widely investigated in bulk MOSFETs [1], UTB MOSFETs [2] and FinFETs [3]. However, study on stressed Si Gate-All-Around (GAA) NWs is still quite limited [4], especially on (110) SOI. In this work, μeff as well as Ion modulations in (110) Si GAA NWs nFETs are studied under uniaxial tensile stress for the first time. It is observed that mobility enhancement in nanowires can be achieved by longitudinal stress in both [100]- and [110]-directed NW nFETs, which are similar to those in bulk MOSFETs [1] and FinFETs [3]. Furthermore, it is also found that larger enhancements can be obtained in narrower NWs, which is promising for future device scaling down. Underlying physical mechanisms are discussed here.