Patent ID: 7573065

Claim:
A method for evaluating a field-effect transistor, comprising: forming a potential difference between a first terminal electrically connected to a source region of the field-effect transistor and a second terminal electrically connected to a drain region of the field-effect transistor; applying monopulse voltage to a gate electrode of the field-effect transistor to change the field-effect transistor from a depletion state to an inversion state; measuring temporal change in source current flowing through the first terminal when the monopulse voltage is applied; measuring temporal change in drain current flowing through the second terminal when the monopulse voltage is applied; obtaining a channel current in an operating state of the field-effect transistor, based on a current value calculated by dividing an algebraic difference between the source current and the drain current by 2; obtaining a quantity of inversion layer charge in the operating state of the field-effect transistor, based on a temporally integrated current value calculated as an algebraic sum of the source current and the drain current; and obtaining mobility of a carrier based on the channel current and the quantity of the inversion layer charge.