Semiconductor device

A semiconductor device comprising:

• a substrate containing a semiconductor material;
• a first transistor formed using the semiconductor material, the first transistor including a channel formation region, a source region, a drain region, a first gate insulating layer, and a first gate electrode;
• an insulating layer formed over the first transistor;
• a second transistor formed over the insulating layer, the second transistor including an oxide semiconductor layer, a source, a drain electrode, a second gate insulating layer, and a second gate electrode;
• a first connection electrode;
• a second connection electrode;
• and
• a third connection electrode formed over the second connection electrode,
• wherein the first connection electrode is provided between the first gate electrode and one of the source electrode and the drain electrode,
• wherein the second connection electrode and the third connection electrode are provided between one of the source region and the drain region and the other of the source electrode and the drain electrode,
• wherein one of the source electrode and the drain electrode is electrically connected to the first gate electrode with the oxide semiconductor layer therebetween,
• wherein the other of the source electrode and the drain electrodes is electrically connected to one of the source region and the drain region with the oxide semiconductor layer therebetween, and
• wherein the oxide semiconductor layer overlaps with at least a part of the source region or the drain region.