Abstract: 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.

Abstract: A semiconductor structure is provided. The semiconductor structure includes a first gate stack wrapping around first nanostructures, a second gate stack wrapping around second nanostructures, a gate isolation structure interposing between the first gate stack and the second gate stack, a first source/drain feature adjoining the first nanostructures, a second source/drain feature adjoining the second nanostructures, and a source/drain spacer structure interposing between the first source/drain feature and the second source/drain feature. The gate isolation structure covers a sidewall of the source/drain spacer structure.

Abstract: A method for forming a semiconductor structure is provided. The method includes forming a fin structure over a substrate. The fin structure includes a protection layer and alternating first and second semiconductor layers over the protection layer. The method also includes etching the fin structure to form a source/drain recess, forming a sacrificial contact in the source/drain recess, forming a source/drain feature over the sacrificial contact in the source/drain recess, removing the first semiconductor layers of the fin structure, thereby forming a plurality of nanostructures, forming a gate stack wrapping around the nanostructures, removing the substrate thereby exposing the protection layer and the sacrificial contact and replacing the sacrificial contact with a contact plug.

Abstract: A method for forming a gate all around transistor includes forming a plurality of semiconductor nanosheets. The method includes forming a cladding inner spacer between a source region of the transistor and a gate region of the transistor. The method includes forming sheet inner spacers between the semiconductor nanosheets in a separate deposition process from the cladding inner spacer.

Abstract: A semiconductor device with different configurations of contact structures and a method of fabricating the same are disclosed. The method includes forming first and second fin structures on a substrate, forming n- and p-type source/drain (S/D) regions on the first and second fin structures, respectively, forming first and second contact openings on the n- and p-type S/D regions, respectively, forming a carbon-based layer in the first and second contact openings, performing a remote plasma treatment with radicals on the carbon-based layer to form a remote plasma treated layer, selectively removing a portion of the remote plasma treated layer, forming a p-type work function metal (pWFM) silicide layer on the p-type S/D region, and forming an n-type work function metal (nWFM) silicide layer on the pWFM silicide layer and on the n-type S/D region.

Abstract: A device includes a substrate, a gate structure, a source/drain region, a first silicide layer, a second silicide layer and a contact. The gate structure wraps around at least one vertical stack of nanostructure channels. The source/drain region abuts the gate structure. The first silicide layer includes a first metal component on the source/drain region. The second silicide layer includes a second metal component different than the first metal component, and is on the first silicide layer. The contact is on the second silicide layer.

Abstract: A semiconductor device according to the present disclosure includes a bottom dielectric feature on a substrate, a plurality of channel members directly over the bottom dielectric feature, a gate structure wrapping around each of the plurality of channel members, two first epitaxial features sandwiching the bottom dielectric feature along a first direction, and two second epitaxial features sandwiching the plurality of channel members along the first direction.

Abstract: A semiconductor device structure, along with methods of forming such, are described. The structure includes a stack of semiconductor layers spaced apart from and aligned with each other, a first source/drain epitaxial feature in contact with a first one or more semiconductor layers of the stack of semiconductor layers, and a second source/drain epitaxial feature disposed over the first source/drain epitaxial feature. The second source/drain epitaxial feature is in contact with a second one or more semiconductor layers of the stack of semiconductor layers. The structure further includes a first dielectric material disposed between the first source/drain epitaxial feature and the second source/drain epitaxial feature and a first liner disposed between the first source/drain epitaxial feature and the second source/drain epitaxial feature. The first liner is in contact with the first source/drain epitaxial feature and the first dielectric material.

Abstract: Semiconductor devices using a dielectric structure and methods of manufacturing are described herein. The semiconductor devices are directed towards gate-all-around (GAA) devices that are formed over a substrate and are isolated from one another by the dielectric structure. The dielectric structure is formed over the fin between two GAA devices and cuts a gate electrode that is formed over the fin into two separate gate electrodes. The two GAA devices are also formed with bottom spacers underlying source/drain regions of the GAA devices. The bottom spacers isolate the source/drain regions from the substrate. The dielectric structure is formed with a shallow bottom that is located above the bottoms of the bottom spacers.

Abstract: A semiconductor device and a method of forming the same are provided. A semiconductor device according to the present disclosure includes a first source/drain feature, a second source/drain feature, a first semiconductor channel member and a second semiconductor channel member extending between the first and second source/drain features, and a first dielectric feature and a second dielectric feature each including a first dielectric layer and a second dielectric layer different from the first dielectric layer. The first and second dielectric features are sandwiched between the first and second semiconductor channel members.

Abstract: During a front side process of a wafer, a hard mask layer is formed under a metal portion of a semiconductor device, and an epitaxial layer is deposited to form epitaxial portions of the semiconductor device. In a back side process of the wafer to cut the epitaxial layer, the metal portion is covered and protected by the hard mask layer from damages during etching of the epitaxial layer.

Abstract: A semiconductor device according to the present disclosure includes a bottom dielectric feature on a substrate, a plurality of channel members directly over the bottom dielectric feature, a gate structure wrapping around each of the plurality of channel members, two first epitaxial features sandwiching the bottom dielectric feature along a first direction, and two second epitaxial features sandwiching the plurality of channel members along the first direction.

Abstract: Corner portions of a semiconductor fin are kept on the device while removing a semiconductor fin prior to forming a backside contact. The corner portions of the semiconductor fin protect source/drain regions from etchant during backside processing. The corner portions allow the source/drain features to be formed with a convex profile on the backside. The convex profile increases volume of the source/drain features, thus, improving device performance. The convex profile also increases processing window of backside contact recess formation.

Abstract: Semiconductor device and the manufacturing method thereof are disclosed. An exemplary method comprises alternately forming first semiconductor layers and second semiconductor layers over a substrate, wherein the first semiconductor layers and the second semiconductor layers include different materials and are stacked up along a direction substantially perpendicular to a top surface of the substrate; forming a dummy gate structure over the first and second semiconductor layers; forming a source/drain (S/D) trench along a sidewall of the dummy gate structure; forming inner spacers between edge portions of the first semiconductor layers, wherein the inner spacers are bended towards the second semiconductor layers; and epitaxially growing a S/D feature in the S/D trench, wherein the S/D feature contacts the first semiconductor layers and includes facets forming a recession away from the inner spacers.

Abstract: Corner portions of a semiconductor fin are kept on the device while removing a semiconductor fin prior to forming a backside contact. The corner portions of the semiconductor fin protect source/drain regions from etchant during backside processing. The corner portions allow the source/drain features to be formed with a convex profile on the backside. The convex profile increases volume of the source/drain features, thus, improving device performance. The convex profile also increases processing window of backside contact recess formation.

Abstract: Embodiments of the present disclosure relate to an un-doped or low-doped epitaxial layer formed below the source/drain features. The un-doped or low-doped epitaxial layer protects the source/drain features from damage during replacement gate processes, and also prevent leakage currents in the mesa device. A semiconductor device is disclosed. The semiconductor device includes an epitaxial feature having a dopant of a first concentration, and a source/drain feature in contact with the epitaxial feature. The source/drain feature comprises the dopant of a second concentration, and the second concentration is higher than the first concentration.

Abstract: The present disclosure describes a semiconductor structure with a dielectric liner. The semiconductor structure includes a substrate and a fin structure on the substrate. The fin structure includes a stacked fin structure, a fin bottom portion below the stacked fin structure, and an isolation layer between the stacked fin structure and the bottom fin portion. The semiconductor structure further includes a dielectric liner in contact with an end of the stacked fin structure and a spacer structure in contact with the dielectric liner.

Abstract: Embodiments of the present disclosure relate to an un-doped or low-doped epitaxial layer formed below the source/drain features. The un-doped or low-doped epitaxial layer protects the source/drain features from damage during replacement gate processes, and also prevent leakage currents in the mesa device. A semiconductor device is disclosed. The semiconductor device includes an epitaxial feature having a dopant of a first concentration, and a source/drain feature in contact with the epitaxial feature. The source/drain feature comprises the dopant of a second concentration, and the second concentration is higher than the first concentration.

Abstract: A method of forming a semiconductor device includes forming a fin of alternating layers of semiconductor nanostructures and sacrificial layers, laterally etching sidewall portions of the sacrificial layers, and depositing additional semiconductor material over the sidewalls of the semiconductor nanostructures and sacrificial layers. Following deposition of a dielectric material over the additional semiconductor material and additional etching, the remaining portions of the semiconductor structures and additional semiconductor material collectively form a hammer shape at each opposing side of the fin. Epitaxial source/drain regions formed on the opposing sides of the fin will contact the heads of the hammer shapes.

Abstract: Semiconductor devices using a dielectric structure and methods of manufacturing are described herein. The semiconductor devices are directed towards gate-all-around (GAA) devices that are formed over a substrate and are isolated from one another by the dielectric structure. The dielectric structure is formed over the fin between two GAA devices and cuts a gate electrode that is formed over the fin into two separate gate electrodes. The two GAA devices are also formed with bottom spacers underlying source/drain regions of the GAA devices. The bottom spacers isolate the source/drain regions from the substrate. The dielectric structure is formed with a shallow bottom that is located above the bottoms of the bottom spacers.