Semiconductor device

A semiconductor device comprising:

• a first transistor including silicon in a channel formation region;
• a second transistor over the first transistor, the second transistor including a first gate electrode, a first insulating film over the first gate electrode, an oxide semiconductor film over the first insulating film, a second insulating film over the oxide semiconductor film, and a second gate electrode over the second insulating film;
• a third insulating film and a fourth insulating film over the second transistor;
• a first wiring over the fourth insulating film, the first wiring being electrically connected to a gate electrode of the first transistor and to the oxide semiconductor film via a first opening in the first insulating film, a second opening in the second insulating film, a third opening in the third insulating film, and a fourth opening in the fourth insulating film;
• and
• a second wiring electrically connected to the channel formation region of the first transistor,
• wherein, in a cross-sectional view, the gate electrode of the first transistor and the oxide semiconductor film do not overlap with each other,
• wherein the second wiring and the oxide semiconductor film overlap with each other,
• wherein the oxide semiconductor film comprises a channel formation region of the second transistor,
• wherein, in the cross-sectional view, the first wiring overlaps with the channel formation region of the first transistor,
• wherein, in the cross-sectional view, the first wiring does not overlap with the channel formation region of the second transistor, and
• wherein a region of the first wiring in contact with a top surface of the fourth insulating film overlaps with the gate electrode of the first transistor.

A semiconductor device comprising:

• a first transistor including silicon in a channel formation region;
• a second transistor over the first transistor, the second transistor including a first gate electrode, a first insulating film over the first gate electrode, an oxide semiconductor film over the first insulating film, a second insulating film over the oxide semiconductor film, and a second gate electrode over the second insulating film;
• a third insulating film and a fourth insulating film over the second transistor;
• a first wiring over the fourth insulating film;
• a semiconductor film over the first insulating film;
• and
• a conductive film electrically connected to the semiconductor film and the oxide semiconductor film,
• wherein, in a cross-sectional view, a gate electrode of the first transistor and the oxide semiconductor film do not overlap with each other,
• wherein, in the cross-sectional view, the gate electrode of the first transistor does not overlap with the first gate electrode of the second transistor,
• wherein the oxide semiconductor film comprises a channel formation region of the second transistor,
• wherein, in the cross-sectional view, the first wiring overlaps with the channel formation region of the first transistor,
• wherein a region of the first wiring in contact with a top surface of the fourth insulating film overlaps with the gate electrode of the first transistor,
• wherein the conductive film is configured to function as one of a source electrode and a drain electrode of the second transistor, and
• wherein the conductive film is in direct contact with the semiconductor film and the oxide semiconductor film.