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.

Abstract: A semiconductor device according to the present disclosure includes a first isolation feature and a second isolation feature, a fin structure extending lengthwise along a first direction and sandwiched between the first isolation feature and the second isolation feature along a second direction perpendicular to the first direction, a first channel member disposed over the first isolation feature, a second channel member disposed over the second isolation feature, and a gate structure disposed over and wrapping around the first channel member and the second channel member.

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 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 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 semiconductor structure includes a first fin, which includes a first plurality of suspended nanostructures vertically stacked over one another, each of the first plurality of suspended nanostructure having a center portion that has a first cross section, and a second fin, which includes a second plurality of suspended nanostructures vertically stacked over one another, the first plurality of suspended nanostructures and the second plurality of suspended nanostructures having different material compositions, each of the second plurality of suspended nanostructure having a center portion that has a second cross section, wherein a shape or an area of the first cross section is different from that of the second cross section.

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 semiconductor device that includes a semiconductor fin disposed over a substrate, an isolation structure at least partially surrounding the fin, an epitaxial source/drain (S/D) feature disposed over the semiconductor fin, where an extended portion of the epitaxial S/D feature extends over the isolation structure, and a silicide layer disposed on the epitaxial S/D feature, where the silicide layer covers top, bottom, sidewall, front, and back surfaces of the extended portion of the S/D feature.

Abstract: Semiconductor device and the manufacturing method thereof are disclosed herein. An exemplary method comprises forming a fin over a substrate, wherein the fin comprises a first semiconductor layer and a second semiconductor layer including different semiconductor materials, and the fin comprises a channel region and a source/drain region; forming a dummy gate structure over the channel region of the fin and over the substrate; etching a portion of the fin in the source/drain region to form a trench therein, wherein a bottom surface of the trench is below a bottom surface of the second semiconductor layer; selectively removing an edge portion of the second semiconductor layer in the channel region such that the second semiconductor layer is recessed; forming a sacrificial structure around the recessed second semiconductor layer and over the bottom surface of the trench; and epitaxially growing a source/drain feature in the source/drain region of the fin.

Abstract: Provided are FinFET devices and methods of forming the same. A FinFET device includes a substrate, a first gate strip and a second gate strip. The substrate has at least one first fin in a first region, at least one second fin in a second region and an isolation layer covering lower portions of the first and second fins. The first fin includes a first material layer and a second material layer over the first material layer, and the interface between the first material layer and the second material layer is uneven. The first gate strip is disposed across the first fin. The second gate strip is disposed across the second fin.

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: A semiconductor device according to the present disclosure includes first gate-all-around (GAA) devices in a first device area and a 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: 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.

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 that includes a semiconductor fin disposed over a substrate; an isolation structure at least partially surrounding the fin; an epitaxial source/drain (S/D) feature disposed over the semiconductor fin, wherein an extended portion of the epitaxial S/D feature extends over the isolation structure; and a silicide layer disposed on the epitaxial S/D feature, the silicide layer continuously surrounding the extended portion of the epitaxial S/D feature over the isolation structure.

Abstract: A semiconductor device is provided. The semiconductor device includes a plurality of channel layers stacked over a semiconductor substrate and spaced apart from one another, a source/drain structure adjoining the plurality of channel layers, a gate structure wrapping around the plurality of channel layers, and a first inner spacer between the gate structure and the source/drain structure and between the plurality of channel layers. The first inner spacer is made of an oxide of a semiconductor material.