| abstract |
A semiconductor device having a large threshold voltage is provided. Further, the present invention provides a semiconductor device capable of holding data for a long time. A semiconductor device having a transistor, the transistor comprising a first conductor, a first insulator disposed on the first conductor, and a first insulator. An oxide disposed to overlap with the first conductor, a second insulator disposed on the oxide, and an overlay on the first conductor and the oxide on the second insulator And a second conductor arranged as described above, and a voltage greater than the voltage Vth is applied to the second conductor in a state where the voltage VBG is applied to the first conductor, A channel is formed in the oxide, and −∂V th / ∂V BG is greater than or equal to 0.1 and less than 1.0. [Selected figure] Figure 1 |