Hole Mobility Behavior in Strained SiGe-on-SOI p-MOSFETs

Abstract

A compressive strained SiGe channel grown-on-SOI structure which can be applicable to next generation high performance CMOSs was applied to p-MOSFETs. The mobility behavior depending on effective fields, E eff , was investigated by varying Ge concentrations in the SiGe layer. We confirmed that the mobility enhancement factor increases with both Ge concentration and E eff , and quite depends on E eff . In particular, we demonstrated that hole mobility enhancement factor at the effective fields of 0.13 MV/cm amounted to 1.51 for 34 at% Ge. In addition, we observed that the strain of 0.23 induced by 56.5-at% Ge concentration in SiGe grown-on-SOI structure could not increase hole mobility at the effective fields range from 0.05 to 0.13 MV/cm because of high density of dislocations.

Memory Technologies for Sub-40nm: Materials, Processes, and Structures

“…Channel and source/drain junction engineering such as LASC (localized asymmetric channel doping) is necessary to extend this planar transistor structure down to 90 nm node (14). Around 90nm node, new 3-dimensional transistor structures called RCAT (recess channel array transistors) and S-RCAT (sphere recess channel array transistor) have been introduced (11,12). These structures elongate the effective channel length and improve the short channel effect with much lower channel doping concentration without area penalty.…”

Dislocation sink annihilating threading dislocations in strain-relaxed Si1−xGexlayer

“…In particular, for a high current drivability and fast operating speed, the Ge and SiGe has been researched as a channel material because of their higher carrier (i.e. electron and hole) mobility than Si [8][9][10]. In addition, it has been reported that the Si/SiGe channel demonstrated a better subthreshold slope and higher current drivability than Si channel in tunneling field effect transistor (TFET), which enables to achieve very steep sub-threshold slope lower than 60 mV dec −1 at room temperature due to band-to-band tunneling injection mechanism [11][12][13][14].…”