Abstract: A semiconductor device includes channel layers disposed over a substrate, a source/drain region disposed over the substrate, a gate dielectric layer disposed on and wrapping each of the channel layers, and a gate electrode layer disposed on the gate dielectric layer and wrapping each of the channel layers. Each of the channel layers includes a semiconductor wire made of a core region, and one or more shell regions. The core region has an approximately square-shape cross section and a first shell of the one or more shells forms a first shell region of an approximately rhombus-shape cross section around the core region and is connected to an adjacent first shell region corresponding to a neighboring semiconductor wire.

Abstract: A semiconductor device includes channel layers disposed over a substrate, a source/drain region disposed over the substrate, a gate dielectric layer disposed on and wrapping each of the channel layers, and a gate electrode layer disposed on the gate dielectric layer and wrapping each of the channel layers. Each of the channel layers includes a semiconductor wire made of a first semiconductor material. The semiconductor wire extends into the source/drain region. The semiconductor wire in the source/drain regions is wrapped around by a second semiconductor material.

Abstract: In a method, a fin structure, in which first semiconductor layers and second semiconductor layers are alternately stacked, is formed. A sacrificial gate structure is formed over the fin structure. The first semiconductor layers are etched at a source/drain region of the fin structure, which is not covered by the sacrificial gate structure, thereby forming a first source/drain space in which the second semiconductor layers are exposed. A dielectric layer is formed at the first source/drain space, thereby covering the exposed second semiconductor layers. The dielectric layer and part of the second semiconductor layers are etched, thereby forming a second source/drain space. A source/drain epitaxial layer is formed in the second source/drain space. At least one of the second semiconductor layers is in contact with the source/drain epitaxial layer, and at least one of the second semiconductor layers is separated from the source/drain epitaxial layer.

Abstract: A semiconductor device includes a first plurality of stacked nanowire structures extending in a first direction disposed over a first region of a semiconductor substrate. Each nanowire structure of the first plurality of stacked nanowire structures includes a plurality of nanowires arranged in a second direction substantially perpendicular to the first direction. A nanowire stack insulating layer is between the substrate and a nanowire closest to the substrate of each nanowire structure of the first plurality of stacked nanowire structures. At least one second stacked nanowire structure is disposed over a second region of the semiconductor substrate, and a shallow trench isolation layer is between the first region and the second region of the semiconductor substrate.

Abstract: A semiconductor device includes a fin field effect transistor (FinFET). The FinFET includes a channel disposed on a fin, a gate disposed over the channel and a source and drain. The channel includes at least two pairs of a first semiconductor layer and a second semiconductor layer formed on the first semiconductor layer. The first semiconductor layer has a different lattice constant than the second semiconductor layer. A thickness of the first semiconductor layer is three to ten times a thickness of the second semiconductor layer at least in one pair.

Abstract: Semiconductor device structures are provided. The semiconductor device structure includes a number of first semiconductor wires over a semiconductor substrate, and the first semiconductor wires are vertically spaced apart from each other. The semiconductor device structure includes a first gate stack partially wrapping the first semiconductor wires, and a spacer element adjacent to the first gate stack. Each of the first semiconductor wires has a first portion directly below the spacer element and a second portion directly below the first gate stack, the first portion has a first width, the second portion has a second width, and the first width is greater than the second width.

Abstract: A method includes providing a substrate; forming a first structure over the substrate, the first structure including a first gate trench and a first channel exposed in the first gate trench; forming a second structure over the substrate, the second structure including a second gate trench and a second channel exposed in the second gate trench; depositing a gate dielectric layer covering surfaces of the first and second channels exposed in the respective first and second gate trenches; recessing the gate dielectric layer in the second gate trench to be lower than the gate dielectric layer in the first gate trench; and forming a gate electrode layer over the gate dielectric layer in the first and second gate trenches.

Abstract: In a method of manufacturing a semiconductor device, a fin structure, in which first semiconductor layers and second semiconductor layers are alternately stacked, is formed over a bottom fin structure. A sacrificial gate structure having sidewall spacers is formed over the fin structure. A source/drain region of the fin structure, which is not covered by the sacrificial gate structure, is removed. The second semiconductor layers are laterally recessed. Dielectric inner spacers are formed on lateral ends of the recessed second semiconductor layers. The first semiconductor layers are laterally recessed. A source/drain epitaxial layer is formed to contact lateral ends of the recessed first semiconductor layer. The second semiconductor layers are removed thereby releasing the first semiconductor layers in a channel region. A gate structure is formed around the first semiconductor layers.

Abstract: A semiconductor device includes a fin extending from a substrate. The fin has a source/drain region and a channel region. The channel region includes a first semiconductor layer and a second semiconductor layer disposed over the first semiconductor layer and vertically separated from the first semiconductor layer by a spacing area. A high-k dielectric layer at least partially wraps around the first semiconductor layer and the second semiconductor layer. A metal layer is formed along opposing sidewalls of the high-k dielectric layer. The metal layer includes a first material. The spacing area is free of the first material.

Abstract: A semiconductor device includes a field effect transistor (FET). The FET includes a first channel, a first source and a first drain; a second channel, a second source and a second drain; and a gate structure disposed over the first and second channels. The gate structure includes a gate dielectric layer and a gate electrode layer. The first source includes a first crystal semiconductor layer and the second source includes a second crystal semiconductor layer. The first source and the second source are connected by an alloy layer made of one or more Group IV element and one or more transition metal elements. The first crystal semiconductor layer is not in direct contact with the second crystal semiconductor layer.

Abstract: A device includes a substrate, a first doping portion, a second doping portion, a channel, a semiconductor film, a high-k layer, and a gate. The first doping portion and the second doping portion are over the substrate. The channel is over the substrate and between the first doping portion and the second doping portion. The semiconductor film is around the channel. The high-k layer is around the semiconductor film. The gate is over the high-k layer.

Abstract: In a method of manufacturing a semiconductor device, a fin structure, in which first semiconductor layers and second semiconductor layers are alternately stacked, is formed. A sacrificial gate structure is formed over the fin structure. The first semiconductor layers, the second semiconductor layer and an upper portion of the fin structure at a source/drain region of the fin structure, which is not covered by the sacrificial gate structure, are etched. A dielectric layer is formed over the etched upper portion of the fin structure. A source/drain epitaxial layer is formed. The source/drain epitaxial layer is connected to ends of the second semiconductor wires, and a bottom of the source/drain epitaxial layer is separated from the fin structure by the dielectric layer.

Abstract: Structures and formation methods of a semiconductor device structure are provided. The semiconductor device structure includes a substrate including a first fin portion, a first nanostructure over the first fin portion. The first nanostructure has a dumbbell shape. The first nanostructure includes a semiconductor material layer over the first fin portion, and a cladding layer surrounding the semiconductor material layer. The semiconductor material layer has a rectangular shape, and the cladding layer has a hexagonal or quadrilateral shape. The semiconductor device structure includes a first gate structure surrounding the first nanostructure.

Abstract: A semiconductor device includes channel layers disposed over a substrate, a source/drain region disposed over the substrate, a gate dielectric layer disposed on and wrapping each of the channel layers, and a gate electrode layer disposed on the gate dielectric layer and wrapping each of the channel layers. Each of the channel layers includes a semiconductor wire made of a core region, and one or more shell regions. The core region has an approximately square-shape cross section and a first shell of the one or more shells forms a first shell region of an approximately rhombus-shape cross section around the core region and is connected to an adjacent first shell region corresponding to a neighboring semiconductor wire.

Abstract: A semiconductor device includes a first source/drain feature adjoining first nanostructures, and a first multilayer work function structure surrounding the first nanostructures. The first multilayer work function structure includes a first middle dielectric layer around the first nanostructures and a first metal layer around and in contact with the first middle dielectric layer. The semiconductor device also includes a second source/drain feature adjoining second nanostructures, and a second multilayer work function structure surrounding the second nanostructures. The second multilayer work function structure includes a second middle dielectric layer around the second nanostructures and a second metal layer around and in contact with the second middle dielectric layer. The first middle dielectric layer and the second middle dielectric layer are made of dielectric materials. The second metal layer and the first metal layer are made of the same metal material.

Abstract: A semiconductor device includes a fin extending from a substrate. The fin has a source/drain region and a channel region. The channel region includes a first semiconductor layer and a second semiconductor layer disposed over the first semiconductor layer and vertically separated from the first semiconductor layer by a spacing area. A high-k dielectric layer at least partially wraps around the first semiconductor layer and the second semiconductor layer. A metal layer is formed along opposing sidewalls of the high-k dielectric layer. The metal layer includes a first material. The spacing area is free of the first material.

Abstract: A semiconductor device includes a field effect transistor (FET). The FET includes a first channel, a first source and a first drain; a second channel, a second source and a second drain; and a gate structure disposed over the first and second channels. The gate structure includes a gate dielectric layer and a gate electrode layer. The first source includes a first crystal semiconductor layer and the second source includes a second crystal semiconductor layer. The first source and the second source are connected by an alloy layer made of one or more Group IV element and one or more transition metal elements. The first crystal semiconductor layer is not in direct contact with the second crystal semiconductor layer.

Abstract: In a method of manufacturing a semiconductor device, a fin structure, in which first semiconductor layers and second semiconductor layers are alternately stacked, is formed over a bottom fin structure. A sacrificial gate structure having sidewall spacers is formed over the fin structure. A source/drain region of the fin structure, which is not covered by the sacrificial gate structure, is removed. The second semiconductor layers are laterally recessed. Dielectric inner spacers are formed on lateral ends of the recessed second semiconductor layers. The first semiconductor layers are laterally recessed. A source/drain epitaxial layer is formed to contact lateral ends of the recessed first semiconductor layer. The second semiconductor layers are removed thereby releasing the first semiconductor layers in a channel region. A gate structure is formed around the first semiconductor layers.

Abstract: In a method of manufacturing a semiconductor device, a fin structure, in which first semiconductor layers and second semiconductor layers are alternately stacked, is formed over a bottom fin structure. A sacrificial gate structure having sidewall spacers is formed over the fin structure. A source/drain region of the fin structure, which is not covered by the sacrificial gate structure, is removed. The second semiconductor layers are laterally recessed. Dielectric inner spacers are formed on lateral ends of the recessed second semiconductor layers. The first semiconductor layers are laterally recessed. A source/drain epitaxial layer is formed to contact lateral ends of the recessed first semiconductor layer. The second semiconductor layers are removed thereby releasing the first semiconductor layers in a channel region. A gate structure is formed around the first semiconductor layers.

Abstract: A method of forming a semiconductor device includes providing a semiconductor structure that includes a first semiconductor material extending from a first region to a second region. The method further includes removing a portion of the first semiconductor material in the second region to form a recess, where the recess exposes a sidewall of the first semiconductor material disposed in the first region; forming a dielectric material covering the sidewall; while the dielectric material covers the sidewall, epitaxially growing a second semiconductor material in the second region adjacent the dielectric material; and forming a first fin including the first semiconductor material and a second fin including the second semiconductor material.