Deep sub-micron strained Si_0.85Ge_0.15 channel p-channel Metal-Oxide-Semiconductor Field-Effect Transistors (pMOSFETs) with ultra-thin N₂O-annealed SiN gate dielectric

We have investigated the electrical characteristics of strained Si _0.85Ge_0.15 channel p-channel metal-oxide-semiconductor field-effect transistors (pMOSFETs) with ultra-thin N₂O-annealed SiN gate dielectric. We have found that the thickness of SiGe channel has a great impact on the device characteristics. With controlling the SiGe layer thickness thinner than 15 nm, the device depict a subthreshold swing of 68mV/A, the interface state density of 1 × 10¹¹ eV ^-1·cm^-2, acceptable junction leakage, and more than 50% hole mobility improvement with respect to the Si channel device. Therefore, high quality interface between the gate dielectric and the strained SiGe channel can be achieved by using the N₂O-annealed SiN gate dielectric.