Semiconductor device having oxide semiconductor layer

A semiconductor device comprising:

• a first insulating layer over a substrate;
• an oxide semiconductor layer over the first insulating layer;
• and
• a second insulating layer over the oxide semiconductor layer,
• wherein the first insulating layer and the second insulating layer each contain a phosphorus element at greater than or equal to 1×1019 cm−3 and less than or equal to 3×1021 cm31 3.

A semiconductor device comprising:

• a first insulating layer over a substrate;
• an oxide semiconductor layer on and in contact with the first insulating layer;
• and
• a second insulating layer on and in contact with the oxide semiconductor layer,
• wherein the first insulating layer and the second insulating layer each contain a boron element at greater than or equal to 1×1018 cm−3 and less than or equal to 1×1022 cm−3.

A semiconductor device comprising:

• a first insulating layer over a substrate;
• an oxide semiconductor layer on and in contact with the first insulating layer;
• and
• a second insulating layer on and in contact with the oxide semiconductor layer,
• wherein the first insulating layer and the second insulating layer each contain an aluminum element at greater than or equal to 1×1018 cm−3 and less than or equal to 1×1022 cm −3.

A semiconductor device comprising:

• a first insulating layer over a substrate;
• an oxide semiconductor layer over the first insulating layer;
• and
• a second insulating layer over the oxide semiconductor layer,
• wherein the first insulating layer and the second insulating layer each contain an antimony element at greater than or equal to 1×1019 cm−3 and less than or equal to 3×1021 cm −3.