Abstract: Present disclosure provides a semiconductor structure. The semiconductor structure includes a semiconductor fin and a metal gate. The semiconductor fin has a first portion and a second portion over the first portion. A height of the second portion is greater than a width of the second portion. The metal gate has a bottom portion, an upper portion, and a lateral portion connecting the bottom portion and the upper portion. The bottom portion is between the first portion and the second portion of the semiconductor fin, and the upper portion is over the second portion of the semiconductor fin.

Abstract: A method for forming a semiconductor structure is provided. The method includes forming a semiconductor fin structure including first semiconductor layers and second semiconductor layers alternatingly stacked, laterally recessing the first semiconductor layers of the semiconductor fin structure to form first notches in the first semiconductor layers, forming first passivation layers on first sidewalls of the first semiconductor layers exposed from the first notches, and forming first inner spacer layers in the first notches.

Abstract: Semiconductor structures and methods of fabrication are provided. A method according to the present disclosure includes receiving a workpiece that includes an active region over a substrate and having first semiconductor layers interleaved by second semiconductor layers, and a dummy gate stack over a channel region of the active region, etching source/drain regions of the active region to form source/drain trenches that expose sidewalls of the active region, selectively and partially etching second semiconductor layers to form inner spacer recesses, forming inner spacer features in the inner spacer recesses, forming channel extension features on exposed sidewalls of the first semiconductor layers, forming source/drain features over the source/drain trenches, removing the dummy gate stack, selectively removing the second semiconductor layers to form nanostructures in the channel region, forming a gate structure to wrap around each of the nanostructures. The channel extension features include undoped silicon.

Abstract: Gate spacer that improves performance and methods for fabricating such are disclosed herein. An exemplary device includes a gate stack disposed over a semiconductor layer and a gate spacer disposed on a sidewall of the gate stack. A source/drain feature is disposed in the semiconductor layer and adjacent the gate spacer. A low-k contact etch stop layer is disposed on a top surface and a sidewall of the gate spacer and a portion of the gate spacer is disposed between the low-k contact etch stop layer and the semiconductor layer. A source/drain contact is disposed on the source/drain feature and adjacent the low-k contact etch stop layer.

Abstract: Present disclosure provides a method including: forming a semiconductor stack having at least one SiGe layer; forming a plurality of fins from the semiconductor stack by a first etching operation, each of the plurality of fins comprising a first portion and a second portion over the first portion, the first portion being separated from the second portion by a SiGe portion; forming a poly gate stripe orthogonally over the plurality of fins; forming a recess on each of the plurality of fins abutting the poly gate; recessing the SiGe portion by a second etching operation through the recess; forming a first spacer and a second spacer to surround the SiGe portion; and removing the SiGe portion.

Abstract: A semiconductor device includes semiconductor nanostructures disposed over a substrate, and an electrical isolation region comprising a void disposed over the substrate in a drain/source region. The semiconductor device further includes a source/drain epitaxial layer in contact with the semiconductor nanostructures and disposed over the electrical isolation region in the drain/source region. The source/drain epitaxial layer is disposed over the void. The semiconductor device further includes a gate dielectric layer disposed on and wrapped around each channel region of the semiconductor nanostructures, and a gate electrode layer disposed on the gate dielectric layer and wrapped around each channel region of the semiconductor nanostructures.

Abstract: A first gate-all-around (GAA) transistor is formed on the first fin structure; the first GAA transistor has a channel region within a first plurality of nanostructures. A second GAA transistor is formed on the second fin structure; the second GAA transistor has a second channel region configuration. The second GAA transistor has a channel region within a second plurality of nanostructures. The second plurality of nanostructures is less than the first plurality of nanostructures.

Abstract: A method and structure for doping source and drain (S/D) regions of a PMOS and/or NMOS FinFET device are provided. In some embodiments, a method includes providing a substrate including a fin extending therefrom. In some examples, the fin includes a channel region, source/drain regions disposed adjacent to and on either side of the channel region, a gate structure disposed over the channel region, and a main spacer disposed on sidewalls of the gate structure. In some embodiments, contact openings are formed to provide access to the source/drain regions, where the forming the contact openings may etch a portion of the main spacer. After forming the contact openings, a spacer deposition and etch process may be performed. In some cases, after performing the spacer deposition and etch process, a silicide layer is formed over, and in contact with, the source/drain regions.

Abstract: Gate spacer that improves performance and methods for fabricating such are disclosed herein. An exemplary device includes a gate stack disposed over a semiconductor layer and a gate spacer disposed on a sidewall of the gate stack. A source/drain feature is disposed in the semiconductor layer and adjacent the gate spacer. A low-k contact etch stop layer is disposed on a top surface and a sidewall of the gate spacer and a portion of the gate spacer is disposed between the low-k contact etch stop layer and the semiconductor layer. A source/drain contact is disposed on the source/drain feature and adjacent the low-k contact etch stop layer.

Abstract: A method of fabricating a device includes providing a fin extending from a substrate, where the fin includes an epitaxial layer stack having a plurality of semiconductor channel layers interposed by a plurality of dummy layers. In some embodiments, the method further includes removing a portion of the epitaxial layer stack within a source/drain region of the semiconductor device to form a trench in the source/drain region that exposes lateral surfaces of the plurality of semiconductor channel layers and the plurality of dummy layers. After forming the trench, in some examples, the method further includes performing a dummy layer recess process to laterally etch ends of the plurality of dummy layers to form first recesses along a sidewall of the trench. In some embodiments, the method further includes conformally forming a cap layer along the exposed lateral surfaces of the plurality of semiconductor channel layers and within the first recesses.

Abstract: A method and structure for doping source and drain (S/D) regions of a PMOS and/or NMOS FinFET device are provided. In some embodiments, a method includes providing a substrate including a fin extending therefrom. In some examples, the fin includes a channel region, source/drain regions disposed adjacent to and on either side of the channel region, a gate structure disposed over the channel region, and a main spacer disposed on sidewalls of the gate structure. In some embodiments, contact openings are formed to provide access to the source/drain regions, where the forming the contact openings may etch a portion of the main spacer. After forming the contact openings, a spacer deposition and etch process may be performed. In some cases, after performing the spacer deposition and etch process, a silicide layer is formed over, and in contact with, the source/drain regions.

Abstract: A semiconductor device includes a substrate, an isolation structure, a semiconductor fin, a semiconductor layer, and a gate structure. The isolation structure is disposed over the substrate. The semiconductor fin extends from the substrate and in contact with the isolation structure. The semiconductor layer is disposed on and in contact with the isolation structure. The gate structure covers the semiconductor layer and spaced apart from the semiconductor fin.

Abstract: A method of fabricating a device includes providing a fin extending from a substrate, where the fin includes an epitaxial layer stack having a plurality of semiconductor channel layers interposed by a plurality of dummy layers. In some embodiments, the method further includes removing a portion of the epitaxial layer stack within a source/drain region of the semiconductor device to form a trench in the source/drain region that exposes lateral surfaces of the plurality of semiconductor channel layers and the plurality of dummy layers. After forming the trench, in some examples, the method further includes performing a dummy layer recess process to laterally etch ends of the plurality of dummy layers to form first recesses along a sidewall of the trench. In some embodiments, the method further includes conformally forming a cap layer along the exposed lateral surfaces of the plurality of semiconductor channel layers and within the first recesses.

Abstract: Present disclosure provides a method including: forming a semiconductor stack having at least one SiGe layer; forming a plurality of fins from the semiconductor stack by a first etching operation, each of the plurality of fins comprising a first portion and a second portion over the first portion, the first portion being separated from the second portion by a SiGe portion; forming a poly gate stripe orthogonally over the plurality of fins; forming a recess on each of the plurality of fins abutting the poly gate; recessing the SiGe portion by a second etching operation through the recess; forming a first spacer and a second spacer to surround the SiGe portion; and removing the SiGe portion.

Abstract: Present disclosure provides a semiconductor structure, including a semiconductor fin having a first portion and a second portion over the first portion, a first conductive region abutting a first lateral surface of the first portion and a first lateral surface of the second portion, a metal gate having a bottom portion and an upper portion, the bottom portion being between the first portion and the second portion of the semiconductor fin, and the upper portion being over the second portion of the semiconductor fin, and a first spacer between the bottom portion of the metal gate and the first conductive region. A method for manufacturing the semiconductor structure described herein is also provided.

Abstract: Semiconductor devices and methods are provided. In an embodiment, a method includes providing a workpiece including a first hard mask layer on a top surface of a substrate, performing an ion implantation process to form a doped region in the substrate, after the performing of the ion implantation process, annealing the workpiece at temperature T1. The method also includes selectively removing the first hard mask layer, after the selectively removing of the first hard mask layer, performing a pre-bake process at temperature T2, and, after the performing of the pre-bake process, epitaxially growing a vertical stack of alternating channel layers and sacrificial layers on the substrate, where the temperature T2 is lower than the temperature T1.

Abstract: A semiconductor device includes a P-type Field Effect Transistor (PFET) and an NFET. The PFET includes an N-well disposed in a substrate, a first fin structure disposed over the N-well, a first liner layer disposed over the N-well, and a second liner layer disposed over the first liner layer. The first liner layer and the second liner layer include different materials. The NFET includes a P-well disposed in the substrate, a second fin structure disposed over the P-well, a third liner layer disposed over the P-well. The third liner layer and the second liner layer include the same materials.

Abstract: In a method of manufacturing a semiconductor device a fin structure is formed in which first semiconductor layers and second semiconductor layers are alternately stacked over a substrate. A sacrificial gate structure is formed over the fin structure. A source/drain region of the fin structure that is not covered by the sacrificial gate structure is etched to form a source/drain space. An isolation region is formed at a bottom portion of the source/drain space. A source/drain epitaxial layer is formed over the isolation region in the source/drain space, and a void region in the isolation region is produced between the source/drain epitaxial layer and the substrate to cause electrical isolation between the source/drain region and the substrate.

Abstract: A method for forming a semiconductor structure is provided. The method includes forming a semiconductor fin structure including first semiconductor layers and second semiconductor layers alternatingly stacked, laterally recessing the first semiconductor layers of the semiconductor fin structure to form first notches in the first semiconductor layers, forming first passivation layers on first sidewalls of the first semiconductor layers exposed from the first notches, and forming first inner spacer layers in the first notches.

Abstract: A FinFET device structure and method for forming the same is provided. The FinFET device structure includes an isolation structure formed over a substrate, and a gate structure formed over the isolation structure. The FinFET device structure includes a first dielectric layer formed over the isolation structure and adjacent to the gate structure and a source/drain (S/D) contact structure formed in the first dielectric layer. The FinFET device structure also includes a deep contact structure formed through the first dielectric layer and adjacent to the S/D contact structure. The deep contact structure is through the isolation structure, and a bottom surface of the S/D contact structure is higher than a bottom surface of the deep contact structure.