A semiconductor device including a substrate, a first transistor and a second transistor is provided. The first transistor includes a first gate structure over the first semiconductor fin. The first gate structure includes a first high-k layer and a first work function layer sequentially disposed on the substrate, a material of the first work function layer may include metal carbide and aluminum, and a content of aluminum in the first work function layer is less than 10% atm. The second transistor includes a second gate structure. The second gate structure includes a second high-k layer and a second work function layer sequentially disposed on the substrate. A work function of the first work function layer is greater than a work function of the second work function layer.

A semiconductor structure is provided. The semiconductor structure includes nanostructures stacked over a substrate and spaced apart from one another, gate dielectric layers wrapping around the nanostructures respectively, nitride layers wrapping around the gate dielectric layers respectively, oxide layers wrapping around the nitride layers respectively, work function layers wrapping around the oxide layers respectively, and a metal fill layer continuously surrounding the work function layers.

A method for forming a semiconductor structure is provided. The method includes forming a fin structure over a substrate and forming an isolation structure over the substrate. In addition, the fin structure is protruded from the isolation structure. The method further includes trimming the fin structure to a first width and forming a Ge-containing material covering the fin structure. The method further includes annealing the fin structure and the Ge-containing material to form a modified fin structure. The method also includes trimming the modified fin structure to a second width.

Gate endcap architectures having relatively short vertical stack, and methods of fabricating gate endcap architectures having relatively short vertical stack, are described. In an example, an integrated circuit structure includes a first semiconductor fin along a first direction. A second semiconductor fin is along the first direction. A trench isolation material is between the first semiconductor fin and the second semiconductor fin. The trench isolation material has an uppermost surface below a top of the first and second semiconductor fins. A gate endcap isolation structure is between the first semiconductor fin and the second semiconductor fin and is along the first direction. The gate endcap isolation structure is on the uppermost surface of the trench isolation material.

A semiconductor device with air spacers and air caps and a method of fabricating the same are disclosed. The semiconductor device includes a substrate and a fin structure disposed on the substrate. The fin structure includes a first fin portion and a second fin portion. The semiconductor device further includes a source/drain (S/D) region disposed on the first fin portion, a contact structure disposed on the S/D region, a gate structure disposed on the second fin portion, an air spacer disposed between a sidewall of the gate structure and the contact structure, a cap seal disposed on the gate structure, and an air cap disposed between a top surface of the gate structure and the cap seal.

Semiconductor device structures having low-k features and methods of forming low-k features are described herein. Some examples relate to a surface modification layer, which may protect a low-k feature during subsequent processing. Some examples relate to gate spacers that include a low-k feature. Some examples relate to a low-k contact etch stop layer. Example methods are described for forming such features.

The present disclosure provides a semiconductor structure having a fin structure. The semiconductor includes a substrate defined with an active region. A first gate structure is disposed in the active region and includes a dielectric material. A second gate structure is disposed in the active region and includes the dielectric material. A fin structure having a first top surface is arranged to alternate with the first gate structure and the second gate structure. The first gate structure has a second top surface and the second gate structure has a third top surface. The second top surface and the third top surface are lower than the first top surface.

A semiconductor structure and a forming method thereof are provided. One form of a semiconductor structure includes: a first device structure, including a first substrate and a first device formed on the first substrate, the first device including a first channel layer structure located on the first substrate, a first device gate structure extending across the first channel layer structure, and a first source-drain doping region located in the first channel layer structure on two sides of the first device gate structure; and a second device structure, located on a front surface of the first device structure, including a second substrate located on the first device structure and a second device formed on the second substrate, the second device including a second channel layer structure located on the second substrate, a second device gate structure extending across the second channel layer structure, and a second source-drain doping region located in the second channel layer structure on two sides of the second device gate structure, where projections of the second channel layer structure and the first channel layer structure onto the first substrate intersect non-orthogonally. The electricity of the first device can be led out according to the present disclosure.

A semiconductor device includes a semiconductor substrate, a semiconductor fin extending from the semiconductor substrate, a gate structure extending across the semiconductor fin, and source/drain semiconductor layers on opposite sides of the gate structure. The source/drain semiconductor layers each have a first thickness over a top side of the semiconductor fin and a second thickness over a lateral side of the semiconductor fin. The first thickness and the second thickness have a difference smaller than about 20 percent of the first thickness.

A device includes a lower semiconductor substrate, a lower gate structure on the lower semiconductor substrate, the lower gate structure comprises a lower gate electrode, a lower interlayer insulating film on the lower semiconductor substrate, an upper semiconductor substrate on the lower interlayer insulating film, an upper gate structure on the upper semiconductor substrate, and an upper interlayer insulating film on the lower interlayer insulating film, the upper interlayer insulating film covers sidewalls of the upper semiconductor substrate The upper gate structure comprises an upper gate electrode extending in a first direction and gate spacers along sidewalls of the upper gate electrode. The upper gate electrode comprises long sidewalls extending in the first direction and short sidewalls in a second direction The gate spacers are on the long sidewalls of the upper gate electrode and are not disposed on the short sidewalls of the upper gate electrode.