Semiconductor structures and methods are provided. An exemplary method according to the present disclosure includes receiving a fin-shaped structure comprising a first channel region and a second channel region, a first and a second dummy gate structures disposed over the first and the second channel regions, respectively. The method also includes removing a portion of the first dummy gate structure, a portion of the first channel region and a portion of the substrate under the first dummy gate structure to form a trench, forming a hybrid dielectric feature in the trench, removing a portion of the hybrid dielectric feature to form an air gap, sealing the air gap, and replacing the second dummy gate structure with a gate stack after sealing the air gap.

A semiconductor structure includes a fin extending from a substrate and oriented lengthwise in a first direction, where the fin includes a stack of semiconductor layers, an isolation feature disposed over the substrate and oriented lengthwise in a second direction perpendicular to the first direction, where the isolation feature is disposed adjacent to the fin, and a metal gate structure having a top portion disposed over the stack of semiconductor layers and a bottom portion interleaved with the stack of semiconductor layers. Furthermore, a sidewall of the bottom portion of the metal gate structure is defined by a sidewall of the isolation feature, and the top portion of the metal gate structure laterally extends over a top surface of the isolation feature.

Semiconductor structures and methods for manufacturing the same are provided. The semiconductor structure includes a substrate and first nanostructures and second nanostructures formed over the substrate. The semiconductor structure also includes a gate structure including a first portion wrapping around the first nanostructures and a second portion wrapping around the second nanostructures. The semiconductor structure also includes a dielectric feature sandwiched between the first portion and the second portion of the gate structure. In addition, the dielectric feature includes a bottom portion and a top portion over the bottom portion, and the top portion of the dielectric feature includes a shell layer and a core portion surrounded by the shell layer.

An integrated circuit (IC) device includes a fin-type active region on a substrate. A mesa-type channel region protrudes from the fin-type active region in a vertical direction. The mesa-type channel region is integrally connected with the fin-type active region. A gate line substantially surrounds a mesa-type channel region on the fin-type active region. A gate dielectric film is between the mesa-type channel region and the gate line. The mesa-type channel region includes: a plurality of round convex portions, which are convex toward the gate line; a concavo-convex sidewall, which includes a portion of each of the plurality of round convex portions and faces the gate line; and at least one void, which is inside the mesa-type channel region.

A method of manufacturing a semiconductor structure and a semiconductor structure are disclosed. The method of manufacturing a semiconductor structure includes: providing a substrate; forming multiple support structures on the substrate, where the multiple support structures are arranged at intervals along a first direction, and a gate trench is formed between every two adjacent support structures; forming a gate structure in the gate trench; and removing a part of each of the support structures, such that each of retained support structures forms two isolation sidewalls spaced apart, the two isolation sidewalls are arranged on opposite sidewalls of the adjacent gate structures respectively, and a filling region is formed by the two isolation sidewalls.

An integrated circuit includes a substrate, an interconnection part, and an isolating region located between the substrate and the interconnection part. A decoy structure is located within the isolating region and includes a silicided sector which is electrically isolated from the substrate.

Embodiments of the disclosure are in the field of advanced integrated circuit structure fabrication and, in particular, 10 nanometer node and smaller integrated circuit structure fabrication and the resulting structures. In an example, an integrated circuit structure includes a first plurality of conductive interconnect lines in and spaced apart by a first ILD layer, wherein individual ones of the first plurality of conductive interconnect lines comprise a first conductive barrier material along sidewalls and a bottom of a first conductive fill material. A second plurality of conductive interconnect lines is in and spaced apart by a second ILD layer above the first ILD layer, wherein individual ones of the second plurality of conductive interconnect lines comprise a second conductive barrier material along sidewalls and a bottom of a second conductive fill material, wherein the second conductive fill material is different in composition from the first conductive fill material.

A semiconductor device includes a gate isolation structure on a shallow trench isolation (STI), a first epitaxial layer on one side of the gate isolation structure, a second epitaxial layer on another side of the gate isolation structure, first fin-shaped structures directly under the first epitaxial layer, and second fin-shaped structures directly under the second epitaxial layer, in which the STI surrounds the first fin-shaped structures and the second fin-shaped structures.

A structure includes a substrate, an isolation structure over the substrate, a fin extending from the substrate and adjacent to the isolation structure, two source/drain (S/D) features over the fin, channel layers suspended over the substrate and connecting the S/D features, a first gate structure wrapping around each of the channel layers in the stack, two outer spacers disposed on two opposing sidewalls of the first gate structure that are on outer surfaces of the stack, inner spacers disposed between the S/D features and the channel layers, and a gate-end dielectric feature over the isolation structure and directly contacting an end of the gate structure. The gate-end dielectric feature includes a first material of a dielectric constant that is higher than dielectric constants of materials included in the outer spacers and the inner spacers.

An IC structure includes a semiconductor fin, first and second gate structures, and an isolation structure. The semiconductor fin extends from a substrate. The first gate structure extends above a top surface of the semiconductor fin by a first gate height. The second gate structure is over the semiconductor fin. The isolation structure is between the first and second gate structures, and has a lower dielectric portion embedded in the semiconductor fin and an upper dielectric portion extending above the top surface of the semiconductor fin by a height that is the same as the first gate height. When viewed in a cross section taken along a longitudinal direction of the semiconductor fin, the upper dielectric portion of the isolation structure has a rectangular profile with a width greater than a bottom width of the lower dielectric portion of the isolation structure.