Patent ID: 7298160

Claim:
A method of determining a gate capacitance of a MOS transistor, the method comprising: (a) obtaining a measured capacitance and a measured dissipation factor by measuring the gate capacitance of the MOS transistor; (b) obtaining a channel resistance and a tunneling resistance of an equivalent circuit of the MOS transistor; (c) setting an initial capacitance and an error dissipation factor, which are required to find a calculated capacitance and a calculated dissipation factor, respectively; (d) calculating a direct dissipation factor using the channel resistance, the tunneling resistance, and the initial capacitance; (e) calculating the calculated dissipation factor using the error dissipation factor, the direct dissipation factor, and the measured dissipation factor; (f) calculating the calculated capacitance using the channel resistance, the tunneling resistance, the initial capacitance, the error dissipation factor, and the measured dissipation factor; (g) detecting the initial capacitance as an accurate gate capacitance of the MOS transistor when it is determined that the calculated capacitance is equal to the measured capacitance and the calculated dissipation factor is equal to the measured dissipation factor; and (h) repeating steps (c) through (g) when at least one of the following conditions is true: (1) the calculated capacitance is not equal to the measured capacitance, and (2) the calculated dissipation factor is not equal to the measured dissipation factor.