Abstract: A semiconductor structure includes a substrate, a first epitaxial layer, a second epitaxial layer, and a transistor. The substrate includes a first pyramid protrusion, a second pyramid protrusion, a third pyramid protrusion, and a fourth pyramid protrusion. The first and second pyramid protrusions are arranged along a first direction, the second and fourth pyramid protrusions are arranged along the first direction, and the first and third pyramid protrusions are arranged along a second direction crossing the first direction. The first epitaxial layer is over the substrate and in contact with the first, second, third, and fourth pyramid protrusions. The second epitaxial layer is over the first epitaxial layer. The transistor is over the second epitaxial layer.

Abstract: In a method of manufacturing a semiconductor device, an opening is formed in an interlayer dielectric layer such that a source/drain region is exposed in the opening. A first semiconductor layer is formed to fully cover the exposed source/drain region within the opening. A heating process is performed to make an upper surface of the first semiconductor layer substantially flat. A conductive contact layer is formed over the first semiconductor layer.

Abstract: In a method of manufacturing a semiconductor device, an opening is formed in an interlayer dielectric layer such that a source/drain region is exposed in the opening. A first semiconductor layer is formed to fully cover the exposed source/drain region within the opening. A heating process is performed to make an upper surface of the first semiconductor layer substantially flat. A conductive contact layer is formed over the first semiconductor layer.

Abstract: A fin including a bottom portion, a first sacrificial layer disposed over the bottom portion, a first semiconductor layer disposed over the first sacrificial layer, a second sacrificial layer disposed over the first semiconductor layer and a second semiconductor layer disposed over the second sacrificial layer, is formed. The second semiconductor layer protrudes from a first insulating layer. A dummy gate is formed over the second semiconductor layer. A sidewall spacer layer is formed on side faces of the dummy gate. A first dielectric layer is formed over the dummy gate and the sidewall spacer layer. The dummy gate is removed, thereby forming a gate space. The first insulating layer is etched in the gate space, thereby exposing the first semiconductor layer and the first and second sacrificial layers. The first and second sacrificial layers are removed. A gate dielectric layer and a gate electrode layer are formed.

Abstract: Methods for forming semiconductor structures are provided. The method includes forming a fin structure over a substrate and forming a dummy gate structure across the fin structure. The method further includes forming a spacer layer on a sidewall of the fin structure at a source/drain region. The method further includes removing at least a portion of the spacer layer to enlarge the source/drain region and forming a source/drain structure in the source/drain region.

Abstract: A fin including a bottom portion, a first sacrificial layer disposed over the bottom portion, a first semiconductor layer disposed over the first sacrificial layer, a second sacrificial layer disposed over the first semiconductor layer and a second semiconductor layer disposed over the second sacrificial layer, is formed. The second semiconductor layer protrudes from a first insulating layer. A dummy gate is formed over the second semiconductor layer. A sidewall spacer layer is formed on side faces of the dummy gate. A first dielectric layer is formed over the dummy gate and the sidewall spacer layer. The dummy gate is removed, thereby forming a gate space. The first insulating layer is etched in the gate space, thereby exposing the first semiconductor layer and the first and second sacrificial layers. The first and second sacrificial layers are removed. A gate dielectric layer and a gate electrode layer are formed.

Abstract: In a method of manufacturing a semiconductor device, a fin structure protruding from a first isolation insulating layer is formed. A second isolation insulating layer made of different material than the first isolation insulating layer is formed so that a first upper portion of the fin structure is exposed. A dummy gate structure is formed over the exposed first upper portion of the first fin structure. The second isolation insulating layer is etched by using the dummy gate structure as an etching mask. The dummy gate structure is removed so that a gate space is formed. The second isolation insulating layer is etched in the gate space so that a second upper portion of the fin structure is exposed from the first isolation insulating layer. A gate dielectric layer and a gate electrode layer are formed over the exposed second portion of the fin structure.

Abstract: In a method of manufacturing a semiconductor device, a fin structure having a bottom portion, an intermediate portion disposed over the bottom portion and an upper portion disposed over the intermediate portion is formed. The intermediate portion is removed at a source/drain region of the fin structure, thereby forming a space between the bottom portion and the upper portion. An insulating layer is formed in the space. A source/drain contact layer is formed over the upper portion. The source/drain contact layer is separated by the insulating layer from the bottom portion of the fin structure.

Abstract: Various strained channel transistors are disclosed herein. An exemplary semiconductor device includes a substrate and a fin structure disposed over the substrate. The fin structure includes a first epitaxial layer disposed on the substrate, a second epitaxial layer disposed on the first epitaxial layer, and a third epitaxial layer disposed on the second epitaxial layer. The second epitaxial layer includes a relaxed transversal stress component and a longitudinal compressive stress component, and the third epitaxial layer has uni-axial strain. A gate structure is disposed on a channel region of the fin structure, such that the gate structure interposes a source region and a drain region of the fin structure.

Abstract: In a method of manufacturing a semiconductor device, a fin structure protruding from a first isolation insulating layer is formed. A second isolation insulating layer made of different material than the first isolation insulating layer is formed so that a first upper portion of the fin structure is exposed. A dummy gate structure is formed over the exposed first upper portion of the first fin structure. The second isolation insulating layer is etched by using the dummy gate structure as an etching mask. The dummy gate structure is removed so that a gate space is formed. The second isolation insulating layer is etched in the gate space so that a second upper portion of the fin structure is exposed from the first isolation insulating layer. A gate dielectric layer and a gate electrode layer are formed over the exposed second portion of the fin structure.

Abstract: In a method of forming a gate-all-around field effect transistor (GAA FET), a bottom support layer is formed over a substrate and a first group of carbon nanotubes (CNTs) are disposed over the bottom support layer. A first support layer is formed over the first group of CNTs and the bottom support layer such that the first group of CNTs are embedded in the first support layer. A second group of carbon nanotubes (CNTs) are disposed over the first support layer. A second support layer is formed over the second group of CNTs and the first support layer such that the second group of CNTs are embedded in the second support layer. A fin structure is formed by patterning at least the first support layer and the second support layer.

Abstract: Various strained channel transistors are disclosed herein. An exemplary semiconductor device includes a substrate and a fin structure disposed over the substrate. The fin structure includes a first epitaxial layer disposed on the substrate, a second epitaxial layer disposed on the first epitaxial layer, and a third epitaxial layer disposed on the second epitaxial layer. The second epitaxial layer includes a relaxed transversal stress component and a longitudinal compressive stress component, and the third epitaxial layer has uni-axial strain. A gate structure is disposed on a channel region of the fin structure, such that the gate structure interposes a source region and a drain region of the fin structure.

Abstract: In a method of forming a gate-all-around field effect transistor (GAA FET), a bottom support layer is formed over a substrate and a first group of carbon nanotubes (CNTs) are disposed over the bottom support layer. A first support layer is formed over the first group of CNTs and the bottom support layer such that the first group of CNTs are embedded in the first support layer. A second group of carbon nanotubes (CNTs) are disposed over the first support layer. A second support layer is formed over the second group of CNTs and the first support layer such that the second group of CNTs are embedded in the second support layer. A fin structure is formed by patterning at least the first support layer and the second support layer.

Abstract: In a method of manufacturing a semiconductor device, an opening is formed in an interlayer dielectric layer such that a source/drain region is exposed in the opening. A first semiconductor layer is formed to fully cover the exposed source/drain region within the opening. A heating process is performed to make an upper surface of the first semiconductor layer substantially flat. A conductive contact layer is formed over the first semiconductor layer.

Abstract: In a method of manufacturing a semiconductor device, an opening is formed in an interlayer dielectric layer such that a source/drain region is exposed in the opening. A first semiconductor layer is formed to fully cover the exposed source/drain region within the opening. A heating process is performed to make an upper surface of the first semiconductor layer substantially flat. A conductive contact layer is formed over the first semiconductor layer.

Abstract: Semiconductor structures and methods for forming the same are provided. The method includes forming a fin structure over a substrate, and the fin structure includes alternately stacked semiconductor material layers and sacrificial layers. The method further includes forming a dummy gate structure, recessing the fin structure to form an opening, forming first source/drain spacers on sidewalls of the sacrificial layers by performing a first atomic layer deposition (ALD) process, and forming source/drain structure in the opening. The method further includes removing the dummy gate structure and the sacrificial layers to expose the semiconductor material layers and forming a gate structure wrapping around the semiconductor material layers.

Abstract: A method includes forming a semiconductor fin over a substrate. A nanowire foundation layer is formed on the semiconductor fin. A nanowire template is formed over the nanowire foundation layer, in which the nanowire template has a through hole exposing a portion of the nanowire foundation layer. A first nanowire is grown from the exposed portion of the nanowire foundation layer, such that the nanowire protrudes out of the through hole. A gate structure is formed over the nanowire foundation layer and wrapping around the first nanowire.

Abstract: Methods for forming semiconductor structures are provided. The method includes forming a fin structure over a substrate and forming a dummy gate structure across the fin structure. The method further includes forming a spacer layer on a sidewall of the fin structure at a source/drain region. The method further includes removing at least a portion of the spacer layer to enlarge the source/drain region and forming a source/drain structure in the source/drain region.

Abstract: A fin including a bottom portion, a first sacrificial layer disposed over the bottom portion, a first semiconductor layer disposed over the first sacrificial layer, a second sacrificial layer disposed over the first semiconductor layer and a second semiconductor layer disposed over the second sacrificial layer, is formed. The second semiconductor layer protrudes from a first insulating layer. A dummy gate is formed over the second semiconductor layer. A sidewall spacer layer is formed on side faces of the dummy gate. A first dielectric layer is formed over the dummy gate and the sidewall spacer layer. The dummy gate is removed, thereby forming a gate space. The first insulating layer is etched in the gate space, thereby exposing the first semiconductor layer and the first and second sacrificial layers. The first and second sacrificial layers are removed. A gate dielectric layer and a gate electrode layer are formed.

Abstract: A semiconductor device and methods of formation are provided. The semiconductor device includes a gate over a channel portion of a fin. The fin includes a first active area of the fin having a first active area top surface coplanar with a first shallow trench isolation (STI) top surface of a first STI portion of STI, and a second active area of the fin having a second active area top surface coplanar with a second STI top surface of a second STI portion of the STI. The method herein negates a need to recess at least one of the fin, the first STI portion or the second STI portion during device formation. Negating a need to recess at least one of the fin, the first STI portion or the second STI portion enhances the semiconductor device formation and is more efficient than a semiconductor device formation that requires the recessing of at least one of a fin, a first STI portion or a second STI portion.