A method includes forming a semiconductor substrate, forming hard mask layers (HMs) over the semiconductor substrate, forming first mandrels over the HMs, forming second mandrels along sidewalls of the first mandrels, forming a protective layer over the first mandrels and the second mandrels, removing a portion of the protective layer to expose portions of the first and the second mandrels, removing the exposed portions of the second mandrels with respect to the exposed portions of the first mandrels, removing remaining portions of the protective layer to expose remaining portions of the first and second mandrels, where the exposed portions of the first mandrels and the remaining portions of the first and second mandrels form a mandrel structure, patterning the HMs using the mandrel structure as an etching mask, and patterning the semiconductor substrate to form a fin structure using the patterned HMs as an etching mask.

A semiconductor device includes a substrate; a semiconductor fin structure disposed over the substrate, wherein the semiconductor fin structure extend along a first lateral direction; a gate structure that straddles a semiconductor fin structure, wherein the gate structure extends along a second lateral direction, the first lateral direction perpendicular to the second lateral direction; a dielectric fin structure that extends along the first lateral direction and is disposed next to the semiconductor structure fin structure; and a gate isolation structure disposed above the dielectric fin structure. The gate isolation structure contacts an upper portion of the gate structure at a first tilted interface.

A semiconductor device includes a substrate; a first fin structure extending along a first lateral direction; a second fin structure extending along the first lateral direction; a first gate structure extending along a second lateral direction and straddles the first fin structure; a second gate structure extending along the second lateral direction and straddles the second fin structure. The semiconductor device further includes a dielectric cut structure that separates the first and second gate structures from each other. The dielectric cut structure extends into the substrate and comprises a first portion and a second portion. A width of the first portion along the second lateral direction increases with increasing depth into the substrate and a width of the second portion along the second lateral direction decreases with increasing depth into the substrate. The second portion is located below the first portion.

In a method of manufacturing a semiconductor device, first and second gate structures are formed. The first (second) gate structure includes a first (second) gate electrode layer and first (second) sidewall spacers disposed on both side faces of the first (second) gate electrode layer. The first and second gate electrode layers are recessed and the first and second sidewall spacers are recessed, thereby forming a first space and a second space over the recessed first and second gate electrode layers and first and second sidewall spacers, respectively. First and second protective layers are formed in the first and second spaces, respectively. First and second etch-stop layers are formed on the first and second protective layers, respectively. A first depth of the first space above the first sidewall spacers is different from a second depth of the first space above the first gate electrode layer.

A semiconductor structure is provided. The semiconductor structure includes a gate structure over a fin structure, and a source/drain structure in the fin structure and adjacent to the gate structure. The source/drain structure includes: a first epitaxial layer over the fin structure, a second epitaxial layer over the first epitaxial layer, and an epitaxial capping layer over the second epitaxial layer. The semiconductor structure also includes a silicide layer formed in contact with the source/drain structure. The silicide layer has a curved bottom surface, and the curved bottom surface of the silicide layer intersects with the second epitaxial layer and the epitaxial capping layer.

Techniques and mechanisms to impose stress on a transistor which includes a channel region and a source or drain region each in a fin structure. In an embodiment, a gate structure of the transistor extends over the fin structure, wherein a first spacer portion is at a sidewall of the gate structure and a second spacer portion adjoins the first spacer portion. Either or both of two features are present at or under respective bottom edges of the spacer portions. One of the features includes a line of discontinuity on the fin structure. The other feature includes a concentration of a dopant in the second spacer portion being greater than a concentration of the dopant in the source or drain region. In another embodiment, the fin structure is disposed on a buffer layer, wherein stress on the channel region is imposed at least in part with the buffer layer.

An exemplary semiconductor device includes a substrate, a first conductive feature, a second conductive feature, and a third conductive feature over the substrate. The first conductive feature has a first top surface and a side surface. The third conductive feature is on the first top surface of the first conductive feature and is spaced away from the second conductive feature. The third conductive feature has a first sidewall and a second sidewall opposing the first sidewall. The first sidewall extends between the first conductive feature and the second conductive feature. At least a segment of the first sidewall has a first slope. The second sidewall has a second slope. The second slope is greater than the first slope.

The present disclosure provides one embodiment of a semiconductor structure. The semiconductor structure includes a first active region and a second fin active region extruded from a semiconductor substrate; an isolation featured formed in the semiconductor substrate and being interposed between the first and second fin active regions; a dielectric gate disposed on the isolation feature; a first gate stack disposed on the first fin active region and a second gate stack disposed on the second fin active region; a first source/drain feature formed in the first fin active region and interposed between the first gate stack and the dielectric gate; a second source/drain feature formed in the second fin active region and interposed between the second gate stack and the dielectric gate; a contact feature formed in a first inter-level dielectric material layer and landing on the first and second source/drain features and extending over the dielectric gate.

A semiconductor device fabricated by forming FET fins from a layered semiconductor structure. The layered semiconductor structure incudes a sacrificial layer. Further by forming dummy gate structures on the FET fins, recessing the FET fins between dummy gate structures, growing source-drain regions between FET fins and the sacrificial layer, replacing active region dummy gate structures with high-k metal gates structures, and replacing the sacrificial layer with a dielectric isolation material, wherein the dielectric isolation material extends across the active region.

A method for shallow trench isolation structures in a semiconductor device and a semiconductor device including the shallow trench isolation structures are disclosed. In an embodiment, the method may include forming a trench in a substrate; depositing a first dielectric liner in the trench; depositing a first shallow trench isolation (STI) material over the first dielectric liner, the first STI material being deposited as a conformal layer; etching the first STI material; depositing a second STI material over the first STI material, the second STI material being deposited as a flowable material; and planarizing the second STI material such that top surfaces of the second STI material are co-planar with top surfaces of the substrate.