Performance Benefits of Diamond-like Carbon Liner Stressor in Strained P-Channel Field-Effect Transistors With Silicon–Germanium Source and Drain

We report the first investigation of the impact of diamond-like carbon (DLC) high-stress liner on strained p-channel metal–oxide–semiconductor field-effect transistors (p-FETs) having silicon–germanium (SiGe) source-and-drain (S/D) stressor. The DLC exhibited a very high compressive stress of $sim$5 GPa. At a fixed $I_{ rm off}$ of $hbox{1}times hbox{10}^{-7} hbox{A}/mu hbox{m}$, the DLC liner stressor contributed to a further 11% $I_{rm on}$ enhancement for p-FETs with $hbox{Si}_{0.75} hbox{Ge}_{0.25}$ S/D. This is the first demonstration that further boost in device performance in a p-FET that is already strained using $hbox{Si}_{0.75}hbox{Ge}_{0.25}$ S/D can be achieved with DLC liner stressor. Due to the extremely high intrinsic compressive stress of the DLC, a very small DLC thickness of $sim$27 nm is sufficient for achieving significant strain effect and performance enhancement.