A semiconductor structure according to the present disclosure includes a substrate, a first base fin and a second base fin arising from the substrate, an isolation structure disposed between the first base fin and the second base fin, first channel members disposed over the first base fin, second channel members disposed over the second base fin, a region isolation feature extending into the substrate, a first gate structure wrapping around each of the first channel members, second gate structure wrapping around each of the second channel members, a first gate cut feature extending through the first gate structure and into the isolation feature, and a second gate cut feature extending though the second gate structure and into the isolation feature. Each of the first gate cut feature and the second gate cut feature are spaced apart from the region isolation feature.

Field effect transistor (FET) devices having a heterogeneous/segmented channel region and methods for fabricating the same are provided. In one example, a fin-like field effect transistor (FinFET) device includes a substrate, a fin structure disposed on the substrate, a segmented channel region formed in the fin structure, two source/drain (S/D) regions separated by the segmented channel region, and a gate structure wrapping around the segmented channel region. The segmented channel region further includes multiple channel segments sequentially arranged in the segmented channel region, and the multiple channel segments include a first channel segment and a second channel segment. The first channel segment includes a first channel barrier material dispersed therein and has a first energy barrier, and the first energy barrier is at least 0.1 electron volts (eV) in a carrier flow path between the two S/D regions when the FinFET device is not activated for operation.

A semiconductor device structure is provided. The semiconductor device structure includes a source/drain (S/D) feature disposed over a substrate and between two adjacent semiconductor layers, an inner spacer disposed between and in contact with one semiconductor layer and the substrate, and a dielectric layer structure disposed between the S/D feature and the substrate. The dielectric layer structure includes a first dielectric layer in contact with the inner spacer and the substrate, and a second dielectric layer nested within the first dielectric layer, wherein a bottom surface and sidewall surfaces of the second dielectric layer are in contact with the first dielectric layer.

A continuous metal on diffusion edge (CMODE) may be used to form a CMODE structure in a semiconductor device after a replacement gate process that is performed to replace the polysilicon dummy gate structures of the semiconductor device with metal gate structures. The CMODE process described herein includes removing a portion of a metal gate structure (as opposed to removing a portion of a polysilicon dummy gate structure) to enable formation of the CMODE structure in a recess left behind by removal of the portion of the metal gate structure.

An integrated circuit and a formation method thereof are provided. The integrated circuit includes: an active structure, formed on a semiconductor substrate, and extending along a first lateral direction; first and second gate lines, extending along a second lateral direction on the semiconductor substrate, and crossing the active structure; an isolation wall, extending along the second lateral direction between the first and second gate lines, and cutting through the active structure; a first source/drain contact, extending along the second lateral direction between the first gate line and the isolation wall, and crossing the active structure; and a first source/drain via, disposed on the first source/drain contact, and laterally extending along the first direction to overlap the isolation wall.

Semiconductor devices and methods for forming the semiconductor devices using diffusion cap layers are provided. The semiconductor devices include a plurality of semiconductor layers vertically separated from one another, a gate structure that comprises a lower portion and an upper portion, wherein the lower portion wraps around each of the plurality of semiconductor layers, and a plurality of diffusion cap layers disposed between and separating the plurality of semiconductor layers and the gate structure. In some embodiments, the plurality of diffusion cap layers function as diffusion barriers for the plurality of semiconductor layers.

Embodiments with present disclosure provides a gate-all-around FET device including a patterned or lowered bottom dielectric layer. The bottom dielectric layer prevents the subsequently formed epitaxial source/drain region from volume loss and induces compressive strain in the channel region to prevent strain loss and channel resistance degradation.

A method includes forming a first dielectric layer over a substrate; forming a first transistor over a first side of the first dielectric layer; removing the substrate to expose a second side of the first dielectric layer opposite to the first side of the second dielectric layer; and forming a second transistor over the second side of the first dielectric layer. Forming the first transistor includes forming a semiconductor layer over the first side of the first dielectric layer; forming a first gate structure over the semiconductor layer; and forming source/drain epitaxy structures on opposite sides of the first gate structure. Forming the second transistor includes forming a semiconductive oxide layer over the second side of the first dielectric layer; forming a second gate structure over the semiconductive oxide layer; and forming source/drain contacts over the semiconductive oxide layer and on opposite sides of the second gate structure.

The disclosed technology generally relates to a complementary field effect transistor (CFET) structure. In one aspect, the CFET structure includes at least one CFET element having a first transistor structure, and a second transistor structure which is arranged above the first transistor structure and which includes a source and/or drain structure. The CFET structure further includes a power rail arranged below the first transistor structure of the at least one CFET element, and a power routing line arranged above the second transistor structure of the at least one CFET element. The power routing line is electrically connected to the source and/or drain structure of the second transistor structure from the top. The at least one CFET element further has a tap connection structure which is arranged to electrically connect the power rail with the source and/or drain structure of the second transistor structure. The tap connection structure is arranged to bypass the first transistor structure on one side.

Embodiments of the present disclosure relate to a method of forming a contact structure on a substrate. The method includes forming a high aspect ratio (HAR) feature within a substrate having a device formed thereon. The device includes a plurality of channels disposed through a polysilicon layer and extending in a first direction, and an isolation layer disposed on the substrate, the polysilicon layer separated from the isolation layer by a dielectric layer. The forming of the HAR feature is formed a first distance in a second direction from the plurality of channels and includes removing a portion of the isolation layer and the polysilicon layer. The method further includes etching the polysilicon layer to expose a top surface of the isolation layer that is opposite to a surface that is disposed on the surface of the substrate, and exposing a metal layer within the HAR feature.