Novel Extended-Pi Shaped Silicon–Germanium Source/Drain Stressors for Strain and Performance Enhancement in p-Channel Tri-Gate Fin-Type Field-Effect Transistor

Strained p-channel tri-gate fin-type field-effect transistor (FinFET) with extended-Pi (e Pi) shaped SiGe source/drain (S/D) is demonstrated with enhanced drive current performance of 33% at a fixed drain induced barrier lowering (DIBL) over FinFET with Pi-SiGe S/D. The e Pi S/D stressor structure can be easily formed by simply using a longer HF cleaning time prior to the growth of SiGe in the S/D regions. The longer HF cleaning step created a recess into the buried oxide which allows SiGe to be grown below the base of the Si fin at the S/D regions, providing additional strain to the channel. Enhancement of device performance was also found to increase with the decrease of fin width and this benefit aggressively scaled tri-gate FinFET for advance technology node.