Abstract: The disclosure is directed towards semiconductor devices and methods of manufacturing the semiconductor devices. The methods include forming fins in a device region and forming other fins in a multilayer stack of semiconductor materials in a multi-channel device region. A topmost nanostructure may be exposed in the multi-channel device region by removing a sacrificial layer from the top of the multilayer stack. Once removed, a stack of nanostructures are formed from the multilayer stack. A native oxide layer is formed to a first thickness over the topmost nanostructure and to a second thickness over the remaining nanostructures of the stack, the first thickness being greater than the second thickness. A gate dielectric is formed over the fins in the device region. A gate electrode is formed over the gate dielectric in the device region and surrounding the native oxide layer in the multi-channel device region.

Abstract: A method includes following steps. A substrate is etched using a hard mask as an etch mask to form a fin. A bottom anti-reflective coating (BARC) layer is over the fin. A recess is formed in the BARC layer to expose a first portion of the hard mask. A protective coating layer is formed at least on a sidewall of the recess in the BARC layer. A first etching step is performed to remove the first portion of the hard mask to expose a first portion of the fin, while leaving a second portion of the fin covered under the protective coating layer and the BARC layer. A second etching step is performed to lower a top surface of the first portion of the fin to below a top surface of the second portion of the fin.

Abstract: An embodiment method includes forming first dummy gate stack and a second dummy gate stack over a semiconductor fin. A portion of the semiconductor fin is exposed by an opening between the first dummy gate stack and the second dummy gate stack. The method further includes etching the portion of the semiconductor fin to extend the opening into the semiconductor fin. A material of the semiconductor fin encircles the opening in a top-down view of the semiconductor fin. The method further includes epitaxially growing a source/drain region in the opening on the portion of the semiconductor fin.

Abstract: A device includes a fin protruding from a semiconductor substrate; a gate stack over and along a sidewall of the fin; a gate spacer along a sidewall of the gate stack and along the sidewall of the fin; an epitaxial source/drain region in the fin and adjacent the gate spacer; and a corner spacer between the gate stack and the gate spacer, wherein the corner spacer extends along the sidewall of the fin, wherein a first region between the gate stack and the sidewall of the fin is free of the corner spacer, wherein a second region between the gate stack and the gate spacer is free of the corner spacer.

Abstract: A semiconductor device may be formed by forming a first fin and a second fin in a first area and a second area of a substrate, respectively; which may be followed by forming of a first dummy gate structure and a second dummy gate structure straddling the first fin and second fin, respectively and forming a sacrificial layer extending along a bottom portion of the second dummy gate structure. The first dummy gate structure may be replaced with a first metal gate structure, while the second dummy gate structure and the sacrificial layer may be replaced with a second metal gate structure.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: A method includes forming a dummy gate stack, etching the dummy gate stack to form an opening, depositing a first dielectric layer extending into the opening, and depositing a second dielectric layer on the first dielectric layer and extending into the opening. A planarization process is then performed to form a gate isolation region including the first dielectric layer and the second dielectric layer. The dummy gate stack is then removed to form trenches on opposing sides of the gate isolation region. The method further includes performing a first etching process to remove sidewall portions of the first dielectric layer, performing a second etching process to thin the second dielectric layer, and forming replacement gates in the trenches.

Abstract: A semiconductor device and method for fabricating a semiconductor device includes etch selectivity tuning to enlarge epitaxy process windows. Through modification of etching processes and careful selection of materials, improvements in semiconductor device yield and performance can be delivered. Etch selectivity is controlled by using dilute gas, using assistive etch chemicals, controlling a magnitude of bias power used in the etching process, and controlling an amount of passivation gas used in the etching process, among other approaches. A recess is formed in a dummy fin in a region of the semiconductor where epitaxial growth occurs to further enlarge the epitaxy process window.

Abstract: A device includes a semiconductive substrate, a stop layer, a semiconductive fin, a fin isolation structure, and a source/drain epitaxial layer. The stop layer is over the semiconductive substrate and includes SiGeOx, SiGe, SiP or SiPOx, where x is greater than 0. The semiconductive fin is over the stop layer. The fin isolation structure is connected to a sidewall of the semiconductive fin. The source/drain epitaxial layer is adjacent to the semiconductive fin. The semiconductive fin is between the source/drain epitaxial layer and the fin isolation structure.

Abstract: A semiconductor structure includes a semiconductor substrate; fin active regions protruded above the semiconductor substrate; and a gate stack disposed on the fin active regions; wherein the gate stack includes a high-k dielectric material layer, and various metal layers disposed on the high-k dielectric material layer. The gate stack has an uneven profile in a sectional view with a first dimension D1 at a top surface, a second dimension D2 at a bottom surface, and a third dimension D3 at a location between the top surface and the bottom surface, and wherein each of D1 and D2 is greater than D3.

Abstract: A semiconductor device includes a substrate. The semiconductor device includes a dielectric fin that is formed over the substrate and extends along a first direction. The semiconductor device includes a gate isolation structure vertically disposed above the dielectric fin. The semiconductor device includes a gate structure extending along a second direction perpendicular to the first direction. The gate structure includes a first portion and a second portion separated by the gate isolation structure and the dielectric fin. The first portion of the gate structure presents a first beak profile and the second portion of the gate structure presents a second beak profile. The first and second beak profiles point toward each other.

Abstract: A semiconductor device is disclosed. The semiconductor device includes a substrate including a semiconductor material. The semiconductor device includes a conduction channel of a transistor disposed above the substrate. The conduction channel and the substrate include a similar semiconductor material. The semiconductor device includes a source/drain region extending from an end of the conduction channel. The semiconductor device includes a dielectric structure. The source/drain region is electrically coupled to the conduction channel and electrically isolated from the substrate by the dielectric structure.

Abstract: A semiconductor device includes a fin projecting upwardly from a substrate; a gate stack engaging the fin; a gate spacer on a sidewall of the gate stack and in contact with the gate stack; and a dielectric layer on the sidewall of the gate stack and in contact with the gate stack, the dielectric layer being vertically between the fin and the gate spacer, wherein the dielectric layer has a thickness small than the gate spacer.

Abstract: A method of fabricating a semiconductor device is disclosed. The method includes providing a fin layer. Dummy gates are formed over the fin layer, where the dummy gates are formed to taper from a smaller width at a top region of the dummy gates to a larger width at a bottom region of the dummy gates. Sidewall spacers are formed on sidewalls of the dummy gates. An interlayer dielectric is formed in regions between the dummy gates and contacts the sidewall spacers. The dummy gates are removed to form openings in the interlayer dielectric and to expose the sidewall spacers on sides of the openings in the interlayer dielectric. The sidewall spacers are etched at a greater rate at a top region of the sidewall spacers than at a bottom region of the sidewall spacers.

Abstract: The disclosure is directed towards semiconductor devices and methods of manufacturing the semiconductor devices. The methods include forming fins in a device region and forming other fins in a multilayer stack of semiconductor materials in a multi-channel device region. A topmost nanostructure may be exposed in the multi-channel device region by removing a sacrificial layer from the top of the multilayer stack. Once removed, a stack of nanostructures are formed from the multilayer stack. A native oxide layer is formed to a first thickness over the topmost nanostructure and to a second thickness over the remaining nanostructures of the stack, the first thickness being greater than the second thickness. A gate dielectric is formed over the fins in the device region. A gate electrode is formed over the gate dielectric in the device region and surrounding the native oxide layer in the multi-channel device region.

Abstract: A method includes forming a first fin and a second fin over a substrate. The method includes forming a first dummy gate structure that straddles the first fin and the second fin. The first dummy gate structure includes a first dummy gate dielectric and a first dummy gate disposed over the first dummy gate dielectric. The method includes replacing a portion of the first dummy gate with a gate isolation structure. The portion of the first dummy gate is disposed over the second fin. The method includes removing the first dummy gate. The method includes removing a first portion of the first dummy gate dielectric around the first fin, while leaving a second portion of the first dummy gate dielectric around the second fin intact. The method includes forming a gate feature straddling the first fin and the second fin, wherein the gate isolation structure intersects the gate feature.

Abstract: A substrate is patterned to form trenches and a semiconductor fin between the trenches. Insulators are formed in the trenches and a first dielectric layer is formed to cover the semiconductor fin and the insulators. A dummy gate strip is formed on the first dielectric layer. Spacers are formed on sidewalls of the dummy gate strip. The dummy gate strip and the first dielectric layer underneath are removed until sidewalls of the spacers, a portion of the semiconductor fin and portions of the insulators are exposed. A second dielectric layer is selectively formed to cover the exposed portion of the semiconductor fin, wherein a thickness of the first dielectric layer is smaller than a thickness of the second dielectric layer. A gate is formed between the spacers to cover the second dielectric layer, the sidewalls of the spacers and the exposed portions of the insulators.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: A semiconductor device may be formed by forming a first fin and a second fin in a first area and a second area of a substrate, respectively; which may be followed by forming of a first dummy gate structure and a second dummy gate structure straddling the first fin and second fin, respectively and forming a sacrificial layer extending along a bottom portion of the second dummy gate structure. The first dummy gate structure may be replaced with a first metal gate structure, while the second dummy gate structure and the sacrificial layer may be replaced with a second metal gate structure.

Abstract: A representative method for manufacturing fin field-effect transistors (FinFETs) includes steps of forming a plurality of fin structures over a substrate, and forming a plurality of isolation structures interposed between adjacent pairs of fin structures. Upper portions of the fin and isolation structures are etched. Epitaxial structures are formed over respective fin structures, with each of the epitaxial structures adjoining adjacent epitaxial structures. A dielectric layer is deposited over the plurality of epitaxial structures with void regions formed in the dielectric layer. The void regions are interposed between adjacent pairs of fin structures.