Transistor, semiconductor device, and electronic device
摘要
說明書
A stack of a plurality of conductive layers formed with the above materials may be used. For example, a layered structure formed using a material containing the above metal element and a conductive material containing oxygen may be used. Alternatively, a layered structure formed using a material containing the above metal element and a conductive material containing nitrogen may be used. Still alternatively, a layered structure formed using a material containing the above metal element, a conductive material containing oxygen, and a conductive material containing nitrogen may be used. Still further alternatively, a layered structure formed using a conductive material containing nitrogen and a conductive material containing oxygen may be used.
Note that in the case where an oxide semiconductor is used for the semiconductor layer and a layered structure formed using a combination of a material including any of the metal elements listed above and a conductive material including oxygen is used as the gate electrode, the conductive material including oxygen is preferably provided on the semiconductor layer side. By providing the conductive material including oxygen on the semiconductor layer side, oxygen released from the conductive material is likely to be supplied to the semiconductor layer.
The electrode 116 may be formed using, for example, a conductive material with high embeddability, such as tungsten or polysilicon. A conductive material with high embeddability and a barrier layer (a diffusion prevention layer) such as a titanium layer, a titanium nitride layer, or a tantalum nitride layer may be used in combination. Note that the electrode 116 may be referred to as a contact plug.
