Replacement high-K/metal-gate High-Ge-content strained SiGe FinFETs with high hole mobility and excellent SS and reliability at aggressive EOT ∼7Å and scaled dimensions down to sub-4nm fin widths

High-Ge-content (HGC) SiGe FinFETs in a “replacement High-K and metal-gate” (RMG) process flow and with aggressive EOT scaling are demonstrated, for the first time. HGC SiGe pMOS FinFETs with high-mobility, record-low RMG long-channel SS=66mV/dec and great short-channel characteristics down to L
_G
=21nm have been demonstrated. Gate stack and transport properties down to sub-4nm fin widths (W
_FIN
) have been also studied for the first time. We demonstrate excellent RMG mobility and reliability at aggressive EOT~7Å, and excellent μ
_eff
=220cm
²
/Vs at N
_inv
=10
¹³
for fins with W
_FIN
~4nm, outperforming state-of-the-art devices at such dimensions and providing very promising results for FinFET scaling for future high-performance FinFET generations.