A semiconductor structure includes a stack of semiconductor layers disposed over a substrate, a metal gate structure disposed over and interleaved with the stack of semiconductor layers, the metal gate structure including a gate electrode disposed over a gate dielectric layer, a first isolation structure disposed adjacent to a first sidewall of the stack of semiconductor layers, where the gate dielectric layer fills space between the first isolation structure and the first sidewall of the stack of semiconductor layers, and a second isolation structure disposed adjacent to a second sidewall of the stack of semiconductor layers, where the gate electrode fills the space between the second isolation structure and the second sidewall of the stack of semiconductor layers.

A semiconductor device includes a substrate including a fin-type active region, the fin-type active region extending in a first direction; a plurality of channel layers on the fin-type active region, the plurality of channel layers including an uppermost channel layer, a lowermost channel layer, and an intermediate channel layer isolated from direct contact with each other in a direction perpendicular to an upper surface of the substrate; a gate electrode surrounding the plurality of channel layers and extending in a second direction intersecting the first direction; a gate insulating film between the plurality of channel layers and the gate electrode; and source/drain regions electrically connected to the plurality of channel layers. In a cross section taken in the second direction, the uppermost channel layer has a width greater than a width of the intermediate channel layer.

A semiconductor device is provided. The semiconductor device includes a substrate including a first dummy region and a second dummy region spaced apart from the first dummy region; a device isolation layer filling a trench between the first dummy region and the second dummy region; a first dummy electrode provided on the first dummy region; a second dummy electrode provided on the second dummy region; a power line extending from the first dummy region to the second dummy region, the power line including an expanded portion provided on the device isolation layer, a width of the expanded portion being larger than a line width of a remaining portion of the power line; a power delivery network provided on a bottom surface of the substrate; and a through via extending through the substrate and the device isolation layer, and electrically connecting the power delivery network to the expanded portion. The through via and the expanded portion vertically overlap.

A method of manufacturing a semiconductor device includes forming a fin structure in which first semiconductor layers and second semiconductor layers are alternatively stacked, the first and second semiconductor layers having different material compositions; forming a sacrificial gate structure over the fin structure; forming a gate spacer on sidewalls of the sacrificial gate structure; etching a source/drain (S/D) region of the fin structure, which is not covered by the sacrificial gate structure and the gate spacer, thereby forming an S/D trench; laterally etching the first semiconductor layers through the S/D trench, thereby forming recesses; selectively depositing an insulating layer on surfaces of the first and second semiconductor layers exposed in the recesses and the S/D trench, but not on sidewalls of the gate spacer; and growing an S/D epitaxial feature in the S/D trench, thereby trapping air gaps in the recesses.

A semiconductor device is provided. The semiconductor device includes a plurality of first semiconductor nanostructures formed over a substrate, and a first S/D structure formed on sidewall surfaces of the first semiconductor nanostructures. The semiconductor device includes a plurality of second semiconductor nanostructures formed over the substrate, and a second S/D structure formed on sidewall surfaces of the second semiconductor nanostructures. The semiconductor device includes an isolation structure formed between the first S/D structure and the second S/D structure, and the isolation structure has a first sidewall surface in direct contact with the first S/D structure and a second sidewall surface in direct contact with the second S/D structure.

Methods for fabricating a transistor arrangement of an IC structure by using a placeholder for backside contact formation, as well as related semiconductor devices, are disclosed. An example method includes forming, in a support structure (e.g., a substrate, a chip, or a wafer), a dielectric placeholder for a backside contact as the first step in the method. A nanosheet superlattice is then grown laterally over the dielectric placeholder, and a stack of nanoribbons is formed based on the superlattice. The nanoribbons are processed to form S/D regions and gate stacks for future transistors. The dielectric placeholder remains in place until the support structure is transferred to a carrier wafer, at which point the dielectric placeholder is replaced with the backside contact. Use of a placeholder for backside contact formation allows alignment of contact from the backside to appropriate device ports of a transistor arrangement.

A semiconductor device includes a first and second active regions extending in a first direction and having respective first and second widths in a second direction, the second width greater than the first width, a connection region connected to the first and second active regions and having a third width, between the first and second widths in the second direction, first and second gate structures respectively intersecting the first and second active regions and extending in the second direction, and a dummy structure intersecting at least a portion of the connection region, extending in the second direction, and between the first and second gate structures in the first direction. The dummy structure includes first and second pattern portions spaced apart from a side surface of the first gate structure by respective first and second distances in the first direction, the second distance greater than the first distance.

A method and structures are used to fabricate a nanosheet semiconductor device. Nanosheet fins including nanosheet stacks including alternating silicon (Si) layers and silicon germanium (SiGe) layers are formed on a substrate and etched to define a first end and a second end along a first axis between which each nanosheet fin extends parallel to every other nanosheet fin. The SiGe layers are undercut in the nanosheet stacks at the first end and the second end to form divots, and a dielectric is deposited in the divots. The SiGe layers between the Si layers are removed before forming source and drain regions of the nanosheet semiconductor device such that there are gaps between the Si layers of each nanosheet stack, and the dielectric anchors the Si layers. The gaps are filled with an oxide that is removed after removing the dummy gate and prior to forming the replacement gate.

A semiconductor structure is provided. The semiconductor structure includes a shallow trench isolation (STI) region on a well region of a substrate, a plurality of transistors, and a power rail. Each of the transistors includes at least one fin, a gate electrode formed on the fin, and a doping region formed on the fin. The fin is formed on the well region, and is extending in a first direction. The gate electrode is extending in a second direction that is perpendicular to the first direction. The power rail is formed in the STI region and below the doping regions of the transistors, and extending in the first direction. Each of the doping regions is electrically connected to the power rail, so as to form a source region of the respective transistor. The power rail is electrically connected to the well region of the substrate.

A method of fabricating a semiconductor device includes providing a dummy structure having a plurality of channel layers, an inner spacer disposed between adjacent channels of the plurality of channel layers and at a lateral end of the channel layers, and a gate structure including a gate dielectric layer and a metal layer interposing the plurality of channel layers. The dummy structure is disposed at an active edge adjacent to an active region. A metal gate etching process is performed to remove the metal layer from the gate structure while the gate dielectric layer remains disposed at a channel layer-inner spacer interface. After performing the metal gate etching process, a dry etching process is performed to form a cut region along the active edge. The gate dielectric layer disposed at the channel layer-inner spacer interface prevents the dry etching process from damaging a source/drain feature within the adjacent active region.