| 摘要 |
PROBLEM TO BE SOLVED: To acquire the threshold voltage of a transistor included in a semiconductor device.SOLUTION: The semiconductor device includes a bit line, a transistor, a retention node, and a capacitor. The transistor has a function of charging or discharging the retention node. The capacitor has a function of retaining a potential of the retention node. A voltage greater than the sum of a writing voltage and a threshold voltage is applied to a gate of the transistor to turn on the transistor, so that a first potential is supplied to the bit line with a reference potential in a floating state. A voltage less than the sum of the writing voltage and the threshold voltage is applied to the gate of the transistor to turn on the transistor, so that a second potential is supplied to the bit line with a reference potential in a floating state. With the first and second potentials, the threshold voltage of the transistor is calculated without being influenced by variations in parasitic capacitance and the storage capacitance of the capacitor.SELECTED DRAWING: Figure 1 |
