A method of manufacturing a semiconductor device includes forming a semiconductor structure extending from a substrate in a first direction and having first and second regions; forming a sacrificial gate pattern intersecting the first region of the semiconductor structure and extending in a second direction perpendicular to the first direction; reducing a width in the second direction of the second region of the semiconductor structure exposed to at least one side of the sacrificial gate pattern; forming at least one recess portion by removing a portion of the second region of the semiconductor structure; forming one or more source/drain regions in the recess portion of the semiconductor structure on at least one side of the sacrificial gate pattern; forming at least one gap region by removing the sacrificial gate pattern; and forming a gate structure by depositing a gate dielectric layer and a gate electrode in the gap region.

Embodiments disclosed herein include transistor devices and methods of forming such transistor devices. In an embodiment a transistor comprises a substrate, and a fin that extends up from the substrate. In an embodiment, the fin comprises a source region, a drain region, and a channel region between the source region and the drain region. In an embodiment, the transistor further comprises and a cavity in the fin, where the cavity is below the channel region. In an embodiment, the transistor further comprises a gate stack over the fin.

An integrated circuit device includes a device isolation trench defining an active area, a gate trench extending in a first direction across the active area and the device isolation film, a gate dielectric film covering an inner wall of the gate trench, and a conductive line filling a part of the gate trench above the gate dielectric film. The active area includes a fin body portion located under the conductive line, and a thinner fin portion protruding from the fin body portion toward the conductive line and having a width less than a width of the fin body portion in the first direction.

A method for forming a semiconductor structure includes forming a fin on a semiconductor substrate. The fin includes channel layers and sacrificial layers stacked one on top of the other in an alternating fashion. The method also includes removing a portion of the fin to form a first opening and expose vertical sidewalls of the channel layers and the sacrificial layers, epitaxially growing a source/drain feature in the first opening from the exposed vertical sidewalls of the channel layers and the sacrificial layers, removing another portion of the fin to form a second opening to expose a vertical sidewall of the source/drain feature, depositing a dielectric layer in the second opening to cover the exposed vertical sidewall of the source/drain feature, and replacing the sacrificial layers with a metal gate structure in the second opening. The dielectric layer separates the source/drain feature from contacting the metal gate structure.

In an embodiment, a method includes: forming a fin extending from a substrate, the fin having a first width and a first height after the forming; forming a dummy gate stack over a channel region of the fin; growing an epitaxial source/drain in the fin adjacent the channel region; and after growing the epitaxial source/drain, replacing the dummy gate stack with a metal gate stack, the channel region of the fin having the first width and the first height before the replacing, the channel region of the fin having a second width and a second height after the replacing, the second width being less than the first width, the second height being less than the first height.

Semiconductor device and the manufacturing method thereof are disclosed. An exemplary method of manufacture comprises receiving a substrate including a semiconductor material stack formed thereon, wherein the semiconductor material stack includes a first semiconductor layer of a first semiconductor material and second semiconductor layer of a second semiconductor material that is different than the first semiconductor material. Patterning the semiconductor material stack to form a trench. The patterning includes performing a first etch process with a first etchant for a first duration and then performing a second etch process with a second etchant for a second duration, where the second etchant is different from the first etchant and the second duration is greater than the first duration. The first etch process and the second etch process are repeated a number of times. Then epitaxially growing a third semiconductor layer of the first semiconductor material on a sidewall of the trench.

In an embodiment, a method includes forming a first fin and a second fin within an insulation material over a substrate, the first fin and the second fin includes different materials, the insulation material being interposed between the first fin and the second fin, the first fin having a first width and the second fin having a second width; forming a first capping layer over the first fin; and forming a second capping layer over the second fin, the first capping layer having a first thickness, the second capping layer having a second thickness different from the first thickness.

A semiconductor device includes a substrate including a fin-type active region, the fin-type active region extending in a first direction; a plurality of channel layers on the fin-type active region, the plurality of channel layers including an uppermost channel layer, a lowermost channel layer, and an intermediate channel layer isolated from direct contact with each other in a direction perpendicular to an upper surface of the substrate; a gate electrode surrounding the plurality of channel layers and extending in a second direction intersecting the first direction; a gate insulating film between the plurality of channel layers and the gate electrode; and source/drain regions electrically connected to the plurality of channel layers. In a cross section taken in the second direction, the uppermost channel layer has a width greater than a width of the intermediate channel layer.

A semiconductor structure and a method for forming a semiconductor structure are provided. In some embodiments, a method is provided. The method includes following operations. A sacrificial gate structure is formed over a fin structure. The sacrificial gate structure includes a sacrificial gate layer and a sacrificial dielectric layer. The sacrificial gate layer is removed to form a gate trench exposing the sacrificial dielectric layer. A doped region is formed in the fi structure covered by the sacrificial dielectric layer. The sacrificial dielectric layer, a portion of the doped region and a portion of the fin structure are removed from the gate trench. An interfacial layer is formed over the fin structure in the gate trench.

In an embodiment, a device includes: an isolation region on a substrate; a first semiconductor fin protruding above the isolation region; a first gate dielectric on a first channel region of the first semiconductor fin, the first gate dielectric including a first interfacial layer and a first high-k dielectric layer; a second semiconductor fin protruding above the isolation region; and a second gate dielectric on a second channel region of the second semiconductor fin, the second gate dielectric including a second interfacial layer and a second high-k dielectric layer, a first portion of the first interfacial layer on the first channel region having a greater thickness than a second portion of the second interfacial layer on the second channel region, the second channel region having a greater height than the first channel region.