Ill-V MOSFETsforDigital Applications withSilicon Co-Integration

Theprospectfortheintroduction ofIII-V semiconductors intothechannel ofn-typeMOSFETsandthusreplace Si with a highmobility material for22nm technology generation andbeyond isexamined indetail. Theso-called implantfree (IF) III-V MOSFETarchitecture option ispresented showing afabricated n-typeIFdemonstrator suitable forscaling. Wethen focus on aprediction ofthe potential performance ofIII-V MOSFETsthrough physicallybased MonteCarlo (MC)device simulations. Animplanted, n-typeIII-V MOSFETsbased on InO.3GaO.7As channel is investigated whenscaled froma gatelength of30nm to 20nm and15nm. Theimpact ofdecisive scattering mechanisms operative atthedielectric/semiconductor interface isdiscussed. Wealsosimulate theIFdevices withlow (Ino.3Gao.7As) andhigh(InO.75Gao.25As) Indium content channel scaled togatelengths of30,20and15nm with equivalent layer thicknesses. TheIFarchitecture isfound todeliver a highdrive currentbecause ofthehighly efficient injection ofelectrons into thechannel andbecause of verylowaccessresistances. However, thelowIndium contentchannel IFtransistor isnotable tofurther increase its drive currentwhenscaled tothe15nm gatelength. Therefore, we examine alsotheperformance ofhigh Indium channeltransistors whichdelivers asteady increase inthedevice performance downtothe15nm gatelength. Material Si Ge GaAs InGaAs InAs InSb u[cm2/Vs] 15003900 8500 14000 25000 78000 vs[cm/s] lo76x1062x 1072.5x 1073.5x 1075x 107 InGaAs=InO 53GaO.47As Table 1:Bulkmobility (u) andbulksaturation velocity (vs) ofsemiconductors considered forthechannel ofatransistor forhigh-performance, low-power digital applications.