In an embodiment, a device includes: a first fin extending from a substrate; a second fin extending from the substrate; a gate spacer over the first fin and the second fin; a gate dielectric having a first portion, a second portion, and a third portion, the first portion extending along a first sidewall of the first fin, the second portion extending along a second sidewall of the second fin, the third portion extending along a third sidewall of the gate spacer, the third portion and the first portion forming a first acute angle, the third portion and the second portion forming a second acute angle; and a gate electrode on the gate dielectric.

Embodiments of the present disclosure provide methods for forming merged source/drain features from two or more fin structures. The merged source/drain features according to the present disclosure have a merged portion with an increased height percentage over the overall height of the source/drain feature. The increase height percentage provides an increased landing range for source/drain contact features, therefore, reducing the connection resistance between the source/drain feature and the source/drain contact features. In some embodiments, the emerged source/drain features include one or more voids formed within the merged portion.

A method includes removing a first dummy gate stack and a second dummy gate stack to form a first trench and a second trench. The first dummy gate stack and the second dummy gate stack are in a first device region and a second device region, respectively. The method further includes depositing a first gate dielectric layer and a second gate dielectric layer extending into the first trench and the second trench, respectively, forming a fluorine-containing layer comprising a first portion over the first gate dielectric layer, and a second portion over the second gate dielectric layer, removing the second portion, performing an annealing process to diffuse fluorine in the first portion into the first gate dielectric layer, and at a time after the annealing process, forming a first work-function layer and a second work-function layer over the first gate dielectric layer and the second gate dielectric layer, respectively.

A method includes providing a substrate, an isolation structure, and a fin extending from the substrate and through the isolation structure. The fin includes a stack of layers having first and second layers that are alternately stacked and have first and second semiconductor materials respectively. A topmost layer of the stack is one of the second layers. The structure further has a sacrificial gate stack engaging a channel region of the fin. The method further includes forming gate spacers and forming sidewall spacers on sidewalls of the fin in a source/drain region of the fin, wherein the sidewall spacers extend above a bottom surface of a topmost one of the first layers. The method further includes etching the fin in the source/drain region, resulting in a source/drain trench; partially recessing the second layers exposed in the source/drain trench, resulting in gaps; and forming dielectric inner spacers inside the gaps.

In an embodiment, a device includes: a first nanostructure; a source/drain region adjoining a first channel region of the first nanostructure, the source/drain region including: a main layer; and a first liner layer between the main layer and the first nanostructure, a carbon concentration of the first liner layer being greater than a carbon concentration of the main layer; an inter-layer dielectric on the source/drain region; and a contact extending through the inter-layer dielectric, the contact connected to the main layer, the contact spaced apart from the first liner layer.

To provide a semiconductor device with less variations, a first insulator is deposited; a stack of first and second oxides and a first conductor is formed over the first insulator; a second insulator is formed over the first insulator and the stack; an opening is formed in the second insulator; a top surface of the second oxide is exposed by removing a region of the first conductor, second and third conductors are formed over the second oxide, and then cleaning is performed; a first oxide film is deposited in contact with a side surface of the first oxide and top and side surfaces of the second oxide; heat treatment is performed on an interface between the second oxide and the first oxide film through the first oxide film; and the second insulator is exposed and a fourth conductor, a third insulator, and a third oxide are formed in the opening.

A method includes forming first nanostructures over a first region of a substrate; forming second nanostructures over a second region of the substrate; forming a first gate structure around the first nanostructures; replacing the second nanostructures with isolation regions; and forming a through via extending through isolation regions and into the substrate.

An integrated circuit includes a first chip bonded to a second chip. The first chip includes gate all around transistors on a substrate. The first chip includes backside conductive vias extending through the substrate to the gate all around transistors. The second chip includes electronic circuitry electrically connected to the transistors by the backside conductive vias.

Embodiments of the disclosure are in the field of advanced integrated circuit structure fabrication and, in particular, buried channel structures integrated with non-planar structures. In an example, an integrated circuit structure includes a first fin structure and a second fin structure above a substrate. A gate structure is on a portion of the substrate directly between the first fin structure and the second fin structure. A source region is in the first fin structure. A drain region is in the second fin structure.

A semiconductor device fabrication method is provided and includes forming first and second stacks each including a dual layer top dielectric cap (TDC), sequentially surrounding each layer and a portion of the dual layer TDC of the first stack with high-k dielectric, a first work function metal (WFM) and a second WFM, sequentially surrounding each layer and a portion of the dual layer TDC of the second stack with the high-k dielectric and the second WFM, forming gate metal around the first and second stacks and recessing the gate metal and the second WFM to a depth defined above a height of an uppermost first WFM horizontal portion.