Semiconductor device and method for driving the same

A semiconductor device comprising:

• a source electrode and a drain electrode being apart from each other;
• a semiconductor layer being in electrical contact with the source electrode and the drain electrode;
• a first insulating layer over at least the semiconductor layer;
• a gate electrode over the first insulating layer;
• a second insulating layer over at least the gate electrode;
• an electric-field control electrode over the second insulating layer;
• a first resistor provided between the source electrode and the gate electrode;
• and
• a second resistor provided between the source electrode and the gate electrode and between the source electrode and the electric-field control electrode,
• wherein the gate electrode overlaps with a first region of the semiconductor layer and the source electrode,
• wherein the gate electrode does not overlap with the drain electrode,
• wherein the electric-field control electrode overlaps with a second region of the semiconductor layer and is provided between the gate electrode and the drain electrode.

A semiconductor device comprising:

• a gate electrode and an electric-field control electrode being apart from each other;
• a first insulating layer over the gate electrode and the electric-field control electrode;
• a semiconductor layer over the first insulating layer;
• a source electrode being on and in electrical contact with the semiconductor layer and overlapping with the gate electrode;
• and
• a drain electrode over the semiconductor layer to be apart from the source electrode,
• wherein the semiconductor layer overlaps with the gate electrode and the electric-field control electrode,
• wherein the drain electrode does not overlap with the electric-field control electrode, and
• wherein the electric-field control electrode is electrically connected to the source electrode.

A semiconductor device comprising:

• a gate electrode and a drain electrode being apart from each other;
• a first insulating layer over the gate electrode and the drain electrode;
• a semiconductor layer being on and in electrical contact with the drain electrode and overlapping with the gate electrode;
• a source electrode being on and in electrical contact with the semiconductor layer and overlapping with the gate electrode;
• a second insulating layer over at least the semiconductor layer;
• an electric-field control electrode over the second insulating layer;
• and
• a wiring over the second insulating layer,
• wherein the electric-field control electrode is provided between the gate electrode and the drain electrode,
• wherein the electric-field control electrode is electrically connected to the source electrode, and
• wherein the wiring is in electrical contact with the drain electrode in an opening portion provided in the first insulating layer.