Patent ID: 11935964
Assignee: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A semiconductor device comprising a transistor,
wherein the transistor includes an oxide semiconductor, a first conductor as a source electrode or a drain electrode over and in contact with the oxide semiconductor, a first insulator in contact with a top surface and a side surface of the first conductor, and a second conductor as a gate electrode embedded in an opening of the first insulator,
wherein the oxide semiconductor includes a channel formation region,
wherein the first conductor includes nitrogen and tantalum, and
wherein the first conductor includes a region where an atomic ratio of nitrogen to tantalum in the first conductor change continuously such that an atomic ratio of nitrogen to tantalum at a bottom surface of the first conductor is higher than an atomic ratio of nitrogen to tantalum at the top surface of the first conductor.