Abstract: A semiconductor structure includes a fin disposed on a substrate, the fin including a channel region comprising a plurality of channels vertically stacked over one another, the channels comprising germanium distributed therein. The semiconductor structure further includes a gate stack engaging the channel region of the fin and gate spacers disposed between the gate stack and the source and drain regions of the fin, wherein each channel of the channels includes a middle section wrapped around by the gate stack and two end sections engaged by the gate spacers, wherein a concentration of germanium in the middle section of the channel is higher than a concentration of germanium in the two end sections of the channel, and wherein the middle section of the channel further includes a core portion and an outer portion surrounding the core portion with a germanium concentration profile from the core portion to the outer portion.

Abstract: Semiconductor structures and methods for forming the same are provided. The semiconductor device includes a fin protruding from a substrate and an isolation structure surrounding the fin. The semiconductor device also includes a first channel layer and a second channel layer formed over the fin and at least partially overlapping the isolation structure. The semiconductor device further includes a gate structure formed in a space between the first channel layer and the second channel layer and wrapping around the first channel layer and the second channel layer.

Abstract: A device includes a first semiconductor strip protruding from a substrate, a second semiconductor strip protruding from the substrate, an isolation material surrounding the first semiconductor strip and the second semiconductor strip, a nanosheet structure over the first semiconductor strip, wherein the nanosheet structure is separated from the first semiconductor strip by a first gate structure including a gate electrode material, wherein the first gate structure partially surrounds the nanosheet structure, and a first semiconductor channel region and a semiconductor second channel region over the second semiconductor strip, wherein the first semiconductor channel region is separated from the second semiconductor channel region by a second gate structure including the gate electrode material, wherein the second gate structure extends on a top surface of the second semiconductor strip.

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: Methods for manufacturing a semiconductor structure is provided. The method for manufacturing the semiconductor structure includes forming nanowire structures over a substrate and forming a gate structure across nanowire structures. The method for manufacturing the semiconductor structure also includes forming a source/drain structure adjacent to the gate structure and forming a Si layer over the source/drain structure. The method for manufacturing the semiconductor structure also includes forming a SiGe layer over the Si layer and oxidizing the SiGe layer to form an oxide layer. The method for manufacturing the semiconductor structure also includes forming a contact through the Si layer over the source/drain structure.

Abstract: The present disclosure provides a semiconductor device. The semiconductor device includes a semiconductor fin over a substrate, an epitaxial source/drain (S/D) feature disposed over the semiconductor fin, first and second dielectric layers over the substrate, and an S/D contact disposed on the epitaxial S/D feature. The first and second dielectric layers have different material compositions. A first sidewall of the epitaxial S/D feature is facing the first dielectric layer, a second sidewall of the epitaxial S/D feature is facing the second dielectric layer, and the S/D contact partially covers a top surface of the epitaxial S/D feature and extends continuously to cover the first sidewall of the epitaxial S/D feature.

Abstract: Provided is a semiconductor device including a semiconductor substrate, a plurality of semiconductor nanosheets, a plurality of source/drain (S/D) features and a gate stack. The semiconductor substrate includes a first fin and a second fin. The first fin has a first width less than a second width of the second fin, and a top surface of the first fin is lower than a top surface of the second fin. The plurality of semiconductor nanosheets are disposed on the first fin and the second fin. The plurality of source/drain (S/D) features are located on the first fin and the second fin and abutting the plurality of semiconductor nanosheets. The gate stack wraps each of the plurality of semiconductor nanosheets.

Abstract: Semiconductor structures and methods for forming the same are provided. The method includes forming a fin protruding from a substrate and forming an isolation structure surrounding the fin. The method also includes epitaxially growing channel fins on sidewalls of the fin over the isolation structure and etching the fin to form a space between the channel fins. The method further includes forming a gate structure to fill the space between the channel fins.

Abstract: A device includes a first semiconductor strip protruding from a substrate, a second semiconductor strip protruding from the substrate, an isolation material surrounding the first semiconductor strip and the second semiconductor strip, a nanosheet structure over the first semiconductor strip, wherein the nanosheet structure is separated from the first semiconductor strip by a first gate structure including a gate electrode material, wherein the first gate structure partially surrounds the nanosheet structure, and a first semiconductor channel region and a semiconductor second channel region over the second semiconductor strip, wherein the first semiconductor channel region is separated from the second semiconductor channel region by a second gate structure including the gate electrode material, wherein the second gate structure extends on a top surface of the second semiconductor strip.

Abstract: Provided is a method of manufacturing a semiconductor device including providing a semiconductor substrate, and forming an epitaxial stack on the semiconductor substrate. The epitaxial stack comprises a plurality of first epitaxial layers interposed by a plurality of second epitaxial layers. The method further includes patterning the epitaxial stack and the semiconductor substrate to form a semiconductor fin, recessing a portion of the semiconductor fin to form source/drain spaces; and laterally removing portions of the plurality of first epitaxial layers exposed by the source/drain spaces to form a plurality of cavities. The method further includes forming inner spacers in the plurality of cavities, performing a treatment process to remove an inner spacer residue in the source/drain spaces, forming S/D features in the source/drain spaces, and forming a gate structure engaging the semiconductor fin.

Abstract: The present disclosure provides a method of semiconductor fabrication. The method includes forming a fin protruding from a substrate, the fin having a first sidewall and a second sidewall opposing the first sidewall; forming a sacrificial dielectric layer on the first and second sidewalls and a top surface of the fin; etching the sacrificial dielectric layer to remove the sacrificial dielectric layer from the second sidewall of the fin; forming a recess in the fin; growing an epitaxial source/drain (S/D) feature from the recess, the epitaxial S/D feature having a first sidewall and a second sidewall opposing the first sidewall, wherein the sacrificial dielectric layer covers the first sidewall of the epitaxial S/D feature; recessing the sacrificial dielectric layer, thereby exposing the first sidewall of the epitaxial S/D feature; and forming an S/D contact on the first sidewall of the epitaxial S/D feature.

Abstract: A semiconductor structure includes a fin disposed on a substrate, the fin including a channel region comprising a plurality of channels vertically stacked over one another, the channels comprising germanium distributed therein. The semiconductor structure further includes a gate stack engaging the channel region of the fin and gate spacers disposed between the gate stack and the source and drain regions of the fin, wherein each channel of the channels includes a middle section wrapped around by the gate stack and two end sections engaged by the gate spacers, wherein a concentration of germanium in the middle section of the channel is higher than a concentration of germanium in the two end sections of the channel, and wherein the middle section of the channel further includes a core portion and an outer portion surrounding the core portion with a germanium concentration profile from the core portion to the outer portion.

Abstract: A method for forming a semiconductor device structure is provided. The method includes forming a gate stack over a substrate. The substrate has a base and a multilayer structure over the base, and the gate stack wraps around the multilayer structure. The method includes partially removing the multilayer structure, which is not covered by the gate stack. The multilayer structure remaining under the gate stack forms a multilayer stack, and the multilayer stack includes a sacrificial layer and a channel layer over the sacrificial layer. The method includes partially removing the sacrificial layer to form a recess in the multilayer stack. The method includes forming an inner spacer layer in the recess and a bottom spacer over a sidewall of the channel layer. The method includes forming a source/drain structure over the bottom spacer. The bottom spacer separates the source/drain structure from the channel layer.

Abstract: A semiconductor device includes a semiconductor substrate having a fin structure, a gate stack across the fin structure, a spacer structure on a sidewall of the gate stack, an epitaxial structure on the semiconductor substrate, and a dielectric structure in the spacer structure. The dielectric structure extends along a lower portion of the spacer structure and across the fin structure.

Abstract: A semiconductor device according to the present disclosure includes first gate-all-around (GAA) devices in a first device area and second GAA devices in a second device area. Each of the first GAA devices includes a first vertical stack of channel members, a first gate structure over and around the first vertical stack of channel members, and a plurality of inner spacer features. Each of the second GAA devices includes a second vertical stack of channel members and a second gate structure over and around the second vertical stack of channel members. Two adjacent channel members of the first vertical stack of channel members are separated by a portion of the first gate structure and at least one of the plurality of inner spacer features. Two adjacent channel members of the second vertical stack of channel members are separated only by a portion of the second gate structure.

Abstract: The present disclosure provides a method of semiconductor fabrication that includes forming a semiconductor fin protruding from a substrate, the semiconductor fin including a plurality of first semiconductor layers of a first semiconductor material and second semiconductor layers of a second semiconductor material alternatively stacked, the second semiconductor material being different from the first semiconductor material in composition; forming a first gate stack on the semiconductor fin; forming a recess in the semiconductor fin within a source/drain (S/D) region adjacent to the first gate stack, a sidewall of the first and second semiconductor material layers being exposed within the recess; performing an etching process to the semiconductor fin, resulting in an undercut below the first gate stack; epitaxially growing on the sidewall of the semiconductor fin to fill in the undercut with a semiconductor extended feature of the first semiconductor material; and growing an epitaxial S/D feature from the rece

Abstract: A method includes forming an epitaxy semiconductor layer over a semiconductor substrate, and etching the epitaxy semiconductor layer and the semiconductor substrate to form a semiconductor strip, which includes an upper portion acting as a mandrel, and a lower portion under the mandrel. The upper portion is a remaining portion of the epitaxy semiconductor layer, and the lower portion is a remaining portion of the semiconductor substrate. The method further includes growing a first semiconductor fin starting from a first sidewall of the mandrel, growing a second semiconductor fin starting from a second sidewall of the mandrel. The first sidewall and the second sidewall are opposite sidewalls of the mandrel. A first transistor is formed based on the first semiconductor fin. A second transistor is formed based on the second semiconductor fin.

Abstract: The present disclosure provides a method of semiconductor fabrication. The method includes forming a fin protruding from a substrate, the fin having a first sidewall and a second sidewall opposing the first sidewall; forming a sacrificial dielectric layer on the first and second sidewalls and a top surface of the fin; etching the sacrificial dielectric layer to remove the sacrificial dielectric layer from the second sidewall of the fin; forming a recess in the fin; growing an epitaxial source/drain (S/D) feature from the recess, the epitaxial S/D feature having a first sidewall and a second sidewall opposing the first sidewall, wherein the sacrificial dielectric layer covers the first sidewall of the epitaxial S/D feature; recessing the sacrificial dielectric layer, thereby exposing the first sidewall of the epitaxial S/D feature; and forming an S/D contact on the first sidewall of the epitaxial S/D feature.

Abstract: A semiconductor structure is provided. The semiconductor structure includes nanostructures over a substrate, a gate stack around the nanostructures, a gate spacer layer alongside the gate stack, an inner spacer layer between the gate spacer layer and the nanostructures, a source/drain feature adjoining the nanostructures, a contact plug over the source/drain feature, and a silicon germanium layer along the surface of the source/drain feature and between the contact plug and the inner spacer layer.

Abstract: A method for forming a semiconductor device structure is provided. The method includes forming a first gate stack and a second gate stack over a substrate. The substrate has a base, a first fin structure, and a second fin structure over the base, the second fin structure is wider than the first fin structure. The method includes partially removing the first fin structure, which is not covered by the first gate stack, and the second fin structure, which is not covered by the second gate stack. The method includes forming an inner spacer layer over the first fin structure, which is not covered by the first gate stack. The method includes forming a first stressor and a second stressor respectively over the inner spacer layer and the second fin structure, which is not covered by the second gate stack.