A doped or undoped silicon carbide film can be deposited using a remote plasma chemical vapor deposition (CVD) technique. One or more silicon-containing precursors are provided to a reaction chamber. Radical species, such as hydrogen radical species, are provided in a substantially low energy state or ground state and interact with the one or more silicon-containing precursors to deposit the silicon carbide film. A co-reactant may be flowed with the one or more silicon-containing precursors, where the co-reactant is a carbon-containing precursor and each silicon-containing precursor is a silane-based precursor with at least a silicon atom having two or more hydrogen atoms bonded to the silicon atom.

A device and method of forming a device are provided. The method includes forming a stack of nanostructure channels over a substrate by forming a source/drain opening. The method also includes forming a sacrificial source/drain in the source/drain opening. The method further includes increasing tensile strain of the stack of nanostructure channels by replacing the sacrificial source/drain with a replacement source/drain having germanium concentration that exceeds that of the sacrificial source/drain.

The present disclosure is directed to method for the fabrication of spacer structures between source/drain epitaxial structures and metal gate structures in nanostructure transistors. The method includes forming a fin structure with alternating first and second nanostructure elements on a substrate. The method also includes etching edge portions of the first nanostructure elements in the fin structure to form spacer cavities, and depositing a spacer layer on the fin structure to fill the spacer cavities. Further, treating the spacer layer with a microwave-generated plasma to form an oxygen concentration gradient within the spacer layer outside the spacer cavities and removing, with an etching process, the treated portion of the spacer layer. During the etching process, a removal rate of the etching process for the treated portion of the spacer layer is based on an oxygen concentration within the oxygen concentration gradient.

A semiconductor device may include a substrate including an active pattern, a channel pattern on the active pattern, the channel pattern including a plurality of semiconductor patterns, which are vertically stacked to be spaced apart from each other, a source/drain pattern connected to the semiconductor patterns, a gate electrode on the semiconductor patterns, a backbone structure on a side surface of the gate electrode, and a first air gap pattern interposed between the backbone structure and each of the semiconductor patterns. The gate electrode may be extended to face a top surface, a side surface, and a bottom surface of each of the semiconductor patterns, and the first air gap pattern may be provided on an opposite side surface of each of the semiconductor patterns.

An integrated circuit device includes a fin-type active area extending in a first horizontal direction on a substrate, a channel area on the fin-type active area, a gate line surrounding the channel area on the fin-type active area and extending in a second horizontal direction crossing the first horizontal direction, an insulating spacer structure covering gate sidewalls of the gate line and channel sidewalls of the channel area, wherein the insulating spacer structure includes an air spacer having a first portion facing the gate sidewalls in the first horizontal direction and a second portion facing the channel sidewalls in the second horizontal direction.

A dummy gate is formed over a substrate. A sacrificial layer is formed over the dummy gate. An interlayer dielectric (ILD) is formed over the dummy gate and over the sacrificial layer. The dummy gate is replaced with a metal-containing gate. The sacrificial layer is removed. A removal of the sacrificial layer leaves air gaps around the metal-containing gate. The air gaps are then sealed.

A semiconductor device and a method of forming the same are provided. In an embodiment, an exemplary semiconductor device includes a vertical stack of channel members disposed over a substrate, a gate structure wrapping around each channel member of the vertical stack of channel members, and a source/drain feature disposed over the substrate and coupled to the vertical stack of channel members. The source/drain feature is spaced apart from a sidewall of the gate structure by an air gap and a dielectric layer, and the air gap extends into the source/drain feature.

A memory device includes a stack structure over a substrate, a channel structure extending in the stack structure, and a dielectric layer over the channel structure. The dielectric layer includes a first material. The memory device may also include a drain-select gate (DSG) cut structure extending through the dielectric layer. The DSG cut structure includes a second material different from the first material.

The present disclosure describes a method to form a semiconductor device with air inner spacers. The method includes forming a semiconductor structure on a first side of a substrate. The semiconductor structure includes a fin structure having multiple semiconductor layers on the substrate, an epitaxial structure on the substrate and in contact with the multiple semiconductor layers, a gate structure wrapped around the multiple semiconductor layers, and an inner spacer structure between the gate structure and the epitaxial structure. The method further includes removing a portion of the substrate from a second side of the substrate to expose the epitaxial structure and the inner spacer structure, forming an oxide layer on the epitaxial structure on the second side of the substrate, and removing a portion of the inner spacer structure to form an opening. The second side is opposite to the first side of the substrate.

A semiconductor device includes a base portion on a semiconductor substrate, a channel layer vertically above the base portion and extending parallel to a top surface of the semiconductor substrate, a gate portion between the channel layer and the base portion, a source/drain feature connected to the channel layer, an inner spacer between the source/drain feature and the gate portion, and an air gap between the source/drain feature and the semiconductor substrate. Moreover, a bottom surface of the source/drain feature is exposed in the air gap.