Metal Gate Technology using a Dy2O3 Dielectric Cap Approach for multiple-VT in NMOS FinFETs

In this work, we investigate the possibility of achieving low V
_T
nMOS FinFETs with single metal gate by using a dysprosium oxide (Dy
₂
O
₃
) cap layer inserted between gate dielectric and metal. We determine an optimum ratio between Dy
₂
O
₃
and SiO
₂
gate dielectric thicknesses for low nMOS V
_T
with good process margin and no loss in performance and reliability.