Metal-Gate FinFET Variation Analysis by Measurement and Compact Model

A compact model (CM) for Fin-type FETs (FinFETs) was successfully developed and applied to variability analysis of a fabricated state-of-the-art metal-gate (MG) FinFET. By combining the statistical measurements with the CM calibration, $V_{\rm th}$ variation was, for the first time, broken down into structure-based (silicon fin thickness and gate length) and material-based (gate work function) components. As a result, the measured variation of MG FinFET performance was successfully reproduced by the CM. Characterization using the CM with the measured statistical data provides insight on the gate work function variation of 16 meV in short-channel molybdenum (Mo) gate FinFETs.