Semiconductor device and method for manufacturing the semiconductor device

A semiconductor device comprising:

• a gate electrode layer;
• a gate insulating layer over the gate electrode layer;
• an oxide semiconductor layer over the gate electrode layer with the gate insulating layer therebetween, the oxide semiconductor layer comprising indium, gallium and zinc;
• a source region over the oxide semiconductor layer;
• a drain region over the oxide semiconductor layer, wherein each of the source region and the drain region comprises indium and zinc;
• a source electrode layer on the source region;
• and
• a drain electrode layer on the drain region, wherein each of the source electrode layer and the drain electrode layer comprises copper,
• wherein the oxide semiconductor layer extends beyond outer side edges of the source region and the drain region,
• wherein the source region extends beyond an outer side edge of the source electrode layer, and
• wherein the drain region extends beyond an outer side edge of the drain electrode layer.

A semiconductor device comprising:

• a gate electrode layer;
• a gate insulating layer over the gate electrode layer;
• an oxide semiconductor layer over the gate electrode layer with the gate insulating layer therebetween, the oxide semiconductor layer comprising indium, gallium and zinc;
• a first oxide layer over the oxide semiconductor layer;
• a second oxide layer over the oxide semiconductor layer, wherein each of the first oxide layer and the second oxide layer comprises indium and zinc;
• a first conductive layer on the first oxide layer;
• a second conductive layer on the second oxide layer;
• and
• an insulating film over the first conductive layer and the second conductive layer, wherein the insulating film is in contact with an upper surface of the oxide semiconductor layer between the first conductive layer and the second conductive layer,
• wherein each of the first conductive layer and the second conductive layer comprises copper,
• wherein the oxide semiconductor layer extends beyond outer side edges of the first oxide layer and the second oxide layer,
• wherein the first conductive layer does not extend beyond the outer side edge of the first oxide layer, and
• wherein the second conductive layer does not extend beyond the outer side edge of the second oxide layer.