Semiconductor device, light-emitting device, and electronic device
An object is to prevent an operation defect and to reduce an influence of fluctuation in threshold voltage of a field-effect transistor. A field-effect transistor, a switch, and a capacitor are provided. The field-effect transistor includes a first gate and a second gate which overlap with each other with a channel formation region therebetween, and the threshold voltage of the field-effect transistor varies depending on the potential of the second gate. The switch has a function of determining whether electrical connection between one of a source and a drain of the field-effect transistor and the second gate of the field-effect transistor is established. The capacitor has a function of holding a voltage between the second gate of the field-effect transistor and the other of the source and the drain of the field-effect transistor.
1. A light-emitting device comprising:
a first transistor, a second transistor, a third transistor, a capacitor, and a light emitting element,
wherein the first transistor includes a first gate electrode, a second gate electrode, and a semiconductor layer comprising a channel formation region,
wherein the first transistor has a function of supplying a current to the light emitting element,
wherein the semiconductor layer comprises a region interposed between the first gate electrode and the second gate electrode,
wherein the first gate electrode is electrically connected to a first wiring through the second transistor,
wherein the second gate electrode is electrically connected to a second wiring through the third transistor,
wherein the first wiring has a function of supplying a data signal,
wherein the second wiring has a function of supplying a potential,
wherein one of a source and a drain of the first transistor is directly connected to an electrode of the light emitting element,
wherein a first terminal of the capacitor is electrically connected to the first gate electrode and a second terminal of the capacitor is electrically connected to the one of the source and the drain of the first transistor, and
wherein the electrode of the light emitting element comprises a region overlapping with the first gate electrode and the second gate electrode.
2. The light-emitting device according to claim 1 ,
wherein a gate electrode of the second transistor is electrically connected to a third wiring,
wherein a gate electrode of the third transistor is electrically connected to a fourth wiring.
3. The light-emitting device according to claim 1 , wherein the semiconductor layer is an oxide semiconductor layer.
4. The light-emitting device according to claim 2 , wherein the semiconductor layer is an oxide semiconductor layer.
5. A light-emitting device comprising:
a first transistor, a second transistor, a third transistor, a capacitor, and a light emitting element,
wherein the first transistor includes a first gate electrode, a second gate electrode, and a semiconductor layer comprising a channel formation region,
wherein the first transistor has a function of supplying a current to the light emitting element,
wherein the semiconductor layer comprises a region interposed between the first gate electrode and the second gate electrode,
wherein the first gate electrode is electrically connected to a first wiring through the second transistor,
wherein the second gate electrode is electrically connected to a second wiring through the third transistor,
wherein the first gate electrode is not electrically connected to the second gate electrode,
wherein the first gate electrode is not electrically connected to an electrode of the light emitting element,
wherein the first wiring has a function of supplying a data signal,
wherein the second wiring has a function of supplying a potential,
wherein one of a source and a drain of the first transistor is directly connected to the electrode of the light emitting element,
wherein a first terminal of the capacitor is electrically connected to the first gate electrode and a second terminal of the capacitor is electrically connected to the one of the source and the drain of the first transistor, and
wherein the electrode of the light emitting element comprises a region overlapping with the first gate electrode and the second gate electrode.
6. The light-emitting device according to claim 5 ,
wherein a gate electrode of the second transistor is electrically connected to a third wiring,
wherein a gate electrode of the third transistor is electrically connected to a fourth wiring.
7. A light-emitting device comprising:
a first transistor, a second transistor, a third transistor, a fourth transistor, and a light emitting element,
wherein the first transistor includes a first gate electrode, a second gate electrode, and a semiconductor layer comprising a channel formation region,
wherein the first transistor has a function of supplying a current to the light emitting element,
wherein the semiconductor layer comprises a region interposed between the first gate electrode and the second gate electrode,
wherein the first gate electrode is electrically connected to a first wiring through the second transistor,
wherein the second gate electrode is electrically connected to a second wiring through the third transistor,
wherein the first wiring has a function of supplying a data signal,
wherein the second wiring has a function of supplying a potential,
wherein one of a source and a drain of the first transistor is electrically connected to an electrode of the light emitting element,
wherein the other of the source and the drain of the first transistor is electrically connected to a third wiring through the fourth transistor,
wherein the electrode of the light emitting element comprises a region overlapping with the first gate electrode and the second gate electrode.
8. The light-emitting device according to claim 7 ,
wherein a gate electrode of the second transistor is electrically connected to a fourth wiring,
wherein a gate electrode of the third transistor is electrically connected to a fifth wiring.
9. A light-emitting device comprising:
a first transistor, a second transistor, a third transistor, a fourth transistor, and a light emitting element,
wherein the first transistor includes a first gate electrode, a second gate electrode, and a semiconductor layer comprising a channel formation region,
wherein the first transistor has a function of supplying a current to the light emitting element,
wherein the semiconductor layer comprises a region interposed between the first gate electrode and the second gate electrode,
wherein the first gate electrode is electrically connected to a first wiring through the second transistor,
wherein the second gate electrode is electrically connected to a second wiring through the third transistor,
wherein the first wiring has a function of supplying a data signal,
wherein the second wiring has a function of supplying a potential,
wherein one of a source and a drain of the first transistor is electrically connected to an electrode of the light emitting element,
wherein the other of the source and the drain of the first transistor is electrically connected to a third wiring through the fourth transistor,
wherein the electrode of the light emitting element comprises a region overlapping with the first gate electrode and the second gate electrode,
wherein a current corresponding to the data signal is supplied to the light emitting element in a period during which the third transistor is in an off state and the fourth transistor is in an on state.
10. The light-emitting device according to claim 9 ,
wherein a gate electrode of the second transistor is electrically connected to a fourth wiring,
wherein a gate electrode of the third transistor is electrically connected to a fifth wiring.