A method for forming a semiconductor device is provided. The method includes forming a semiconductor protruding structure over a substrate and surrounding the semiconductor protruding structure with an insulating layer. The method also includes forming a dielectric layer over the insulating layer. The method further includes partially removing the dielectric layer and insulating layer using a planarization process. As a result, topmost surfaces of the semiconductor protruding structure, the insulating layer, and the dielectric layer are substantially level with each other. In addition, the method includes forming a protective layer to cover the topmost surfaces of the dielectric layer. The method includes recessing the insulating layer after the protective layer is formed such that the semiconductor protruding structure and a portion of the dielectric layer protrude from a top surface of a remaining portion of the insulating layer.

In a method of manufacturing a semiconductor device, a first fin structure, a second fin structure, a first wall fin structure and a second wall fin structure are formed over a substrate. The first and second fin structures are disposed between the first and second wall fin structures, and lower portions of the first and second fin structures and the first and second wall fin structures are embedded in the isolation insulating layer and upper portions thereof are exposed from the isolation insulating layer. A sidewall spacer layer is formed on sidewalls of the first and second fin structures. Source/drain regions of the first and second fin structures are recessed. An epitaxial source/drain structure is formed over the recessed first and second fin structures. A width W1 of the first and second fin structures is smaller than a thickness W2 of the sidewall spacer layer.

A semiconductor device and a method of forming the same are provided. The semiconductor device includes a gate stack over an active region and a source/drain region in the active region adjacent the gate stack. The source/drain region includes a first semiconductor layer having a first germanium concentration and a second semiconductor layer over the first semiconductor layer. The second semiconductor layer has a second germanium concentration greater than the first germanium concentration. The source/drain region further includes a third semiconductor layer over the second semiconductor layer and a fourth semiconductor layer over the third semiconductor layer. The third semiconductor layer has a third germanium concentration greater than the second germanium concentration. The fourth semiconductor layer has a fourth germanium concentration less than the third germanium concentration.

A semiconductor device structure is provided. The semiconductor device structure includes a first stacked nanostructure and a second stacked nanostructure formed over a substrate. The semiconductor device structure includes a first gate structure formed over the first stacked nanostructure, and the first gate structure includes a first portion of a gate dielectric layer and a first portion of a filling layer. The semiconductor device structure includes a second gate structure formed over the second stacked nanostructure, and the second gate structure includes a second portion of the gate dielectric layer and a second portion of the filling layer. The semiconductor device structure includes a first isolation layer between the first gate structure and the second gate structure, wherein the first isolation layer has an extending portion which is formed in a recess between the gate dielectric layer and the filling layer.

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.

A method of forming a semiconductor device includes: forming a dummy gate over a fin, where the fin protrudes above a substrate; surrounding the dummy gate with a dielectric material; and replacing the dummy gate with a replacement gate structure, where replacing the dummy gate includes: forming a gate trench in the dielectric material, where forming the gate trench includes removing the dummy gate; forming a metal-gate stack in the gate trench, where forming the metal-gate stack includes forming a gate dielectric layer, a first work function layer, and a gap-filling material sequentially in the gate trench; and enlarging a volume of the gap-filling material in the gate trench.

Isolation schemes for gate-all-around (GAA) transistor devices are provided herein Integrated circuit structures including increased transistor source/drain contact area using a sacrificial source/drain layer are provided herein. In some cases, the isolation schemes include changing the semiconductor nanowires/nanoribbons in a targeted channel region between active or functional transistor devices to electrically isolate those active devices. The targeted channel region is referred to herein as a dummy channel region, as it is not used as an actual channel region for an active or functional transistor device. The semiconductor nanowires/nanoribbons in the dummy channel region can be changed by converting them to an electrical insulator and/or by adding dopant that is opposite in type relative to surrounding source/drain material (to create a p-n junction). The isolation schemes described herein enable neighboring active devices to retain strain in the nanowires/nanoribbons of their channel regions, thereby improving device performance.

A semiconductor device may include a substrate including an active pattern extending in a first direction, a gate electrode running across the active pattern and extending in a second direction intersecting the first direction, a source/drain pattern on the active pattern and adjacent to a side of the gate electrode, an active contact in a contact hole exposing the source/drain pattern, an insulating pattern filling a remaining space of the contact hole in which the active contact is provided, a first via on the active contact, and a second via on the gate electrode. The active contact may include a first segment that fills a lower portion of the contact hole and a second segment that vertically protrudes from the first segment. The first via is connected to the second segment. The insulating pattern is adjacent in the first direction to the second via.

The present disclosure generally relates to semiconductor structures and, more particularly, to single fin structures and methods of manufacture. The structure includes: an active single fin structure; a plurality of dummy fin structures on opposing sides of the active single fin structure; source and drain regions formed on the active single fin structure and the dummy fin structures; recessed shallow trench isolation (STI) regions between the dummy fin structures and the active single fin structure and below a surface of the dummy fin structures; and contacts formed on the source and drain regions of the active single fin structure with a spacing of at least two dummy fin structures on opposing sides of the contacts.

A device includes a semiconductor substrate, a source feature and a drain feature over the semiconductor substrate, a stack of semiconductor layers interposed between the source feature and the drain feature, a gate portion, and an inner spacer of a dielectric material. The gate portion is between two vertically adjacent layers of the stack of semiconductor layers and between the source feature and the drain feature. Moreover, the gate portion has a first sidewall surface and a second sidewall surface opposing the first sidewall surface. The inner spacer is on the first sidewall surface and between the gate portion and the drain feature. The second sidewall surface is in direct contact with the source feature.