Experimental I-V and C-V Analysis of Schottky-Barrier Metal-Oxide-Semiconductor Field Effect Transistors with Epitaxial NiSi2 Contacts and Dopant Segregation

We present an experimental analysis of Schottky-barrier metal-oxide-semiconductor field effect transistors(SBMOSFETs) fabricated on ultrathin body silicon-on-insulator substrates with a steep junction by the dopant implantation into the silicide process. The subthreshold swing of such SB-MOSFETs reaches 69 mV/dec. Emphasis is placed on the capacitance-voltage analysis of p-type SB-MOSFETs. According to the measurements of gate-to-source capacitance Cwith respect to Vat various V, we find that a maximum occurs at the accumulation regime due to the most imbalanced charge distribution along the channel. At each Cpeak, the difference between Vand Vis equal to the Schottky barrier height(SBH) for NiSion highly doped silicon,which indicates that the critical condition of channel pinching off is related with SBH for source/drain on channel. The SBH for NiSion highly doped silicon can affect the pinch-off voltage and the saturation current of SB-MOSFETs.