Advantage of Plasma Doping for Source/Drain Extension in Bulk Fin Field Effect Transistor

The impact of plasma doping (PD) on the formation of source/drain extension (SDE) is demonstrated for a p-type bulk fin field effect transistor (FinFET). The impurity distribution in a narrow fin (15 nm) was analyzed with atom probe tomography (APT) and secondary ion mass spectroscopy (SIMS). The lateral distribution of boron in the Si fin by the PD is similar to the case with conventional beam-line ion implantation (BL). However, the vertical distribution of boron by the PD is much steeper than that by the conventional BL. TCAD simulations show that the driving current of the FinFET fabricated by the PD is 34% higher than that of the FinFET fabricated by the BL under the same off-leakage current. Therefore, the PD is a key technology for fabricating the SDE of narrow bulk-FinFETs in the future.