Patent attributes
Capacity-gate voltage characteristics of a field-effect transistor having plural gates are measured against a voltage change in each one of the gates for an inverted MOSFET and for an accumulated MOSFET, respectively. These measurements together with numerical simulations provided from a model for quantum effects are used to determine flat band voltages between the plural gates and a channel. Next, an effective normal electric field is calculated as a vector line integral by using a set of flat band voltages for the measured capacity as a lower integration limit. Lastly, mobility depending on the effective normal electric field is calculated from current-gate voltage characteristic measurements and capacity measurements in a source-drain path, and the calculated mobility is substituted into an equation for a current-voltage curve between source and drain.