Semiconductor device and method for manufacturing semiconductor device

A semiconductor device comprising:

• a first conductive layer;
• a first insulating layer;
• a semiconductor layer;
• a second insulating layer;
• and
• wherein the first conductive layer, the first insulating layer, the semiconductor layer, and the second insulating layer are stacked in this order,
• wherein the first insulating layer contains silicon and nitrogen,
• wherein the semiconductor layer contains a metal oxide,
• wherein the first insulating layer comprises a first region including a surface in contact with the semiconductor layer and a second region other than the first region,
• wherein the first region has a higher concentration of oxygen than the second region, and
• wherein the first region has a lower concentration of hydrogen than the second region.

A semiconductor device comprising:

• a first conductive layer;
• a first insulating layer;
• a semiconductor layer;
• a second insulating layer;
• and
• wherein the first conductive layer, the first insulating layer, the semiconductor layer, and the second insulating layer are stacked in this order,
• wherein the first insulating layer contains silicon and nitrogen,
• wherein the semiconductor layer contains a metal oxide,
• wherein the second insulating layer contains oxygen,
• wherein the first insulating layer comprises a first region including a surface in contact with the semiconductor layer and a second region other than the first region,
• wherein the first region has a higher concentration of oxygen than the second region,
• wherein the first region has a lower concentration of hydrogen than the second region,
• wherein a first metal oxide film and a second metal oxide film are stacked in the semiconductor layer,
• wherein the first metal oxide film comprises a portion in contact with the first region of the first insulating layer,
• wherein the second metal oxide film comprises a portion in contact with the second insulating layer, and
• wherein the first metal oxide film has lower crystallinity than the second metal oxide film.