Abstract: The present disclosure describes a method to form a backside power rail (BPR) semiconductor device with an air gap. The method includes forming a fin structure on a first side of a substrate, forming a source/drain (S/D) region adjacent to the fin structure, forming a first S/D contact structure on the first side of the substrate and in contact with the S/D region, and forming a capping structure on the first S/D contact structure. The method further includes removing a portion of the first S/D contact structure through the capping structure to form an air gap and forming a second S/D contact structure on a second side of the substrate and in contact with the S/D region. The second side is opposite to the first side.

Abstract: A method includes providing a structure having a gate stack; first gate spacers; a second gate spacer over one of the first gate spacers and having an upper portion over a lower portion; a dummy spacer; an etch stop layer; and a dummy cap. The method further includes removing the dummy cap, resulting in a first void above the gate stack and between the first gate spacers; removing the dummy spacer, resulting in a second void above the lower portion and between the etch stop layer and the upper portion; depositing a layer of a decomposable material into the first and the second voids; depositing a seal layer over the etch stop layer, the first and the second gate spacers, and the layer of the decomposable material; and removing the layer of the decomposable material, thereby reclaiming at least portions of the first and the second voids.

Abstract: An integrated circuit (IC) structure includes a transistor, a front-side interconnection structure, a backside via, and a backside interconnection structure. The transistor includes a source/drain epitaxial structure. The front-side interconnection structure is on a front-side of the transistor. The backside via is connected to the source/drain epitaxial structure of the transistor. The backside interconnection structure is connected to the backside via and includes a conductive feature, a dielectric layer, and a spacer structure. The conductive feature is connected to the backside via. The dielectric layer laterally surrounds the conductive feature. The spacer structure is between the conductive feature and the dielectric layer and has an air gap.

Abstract: A semiconductor structure and a method of forming the same are provided. In an embodiment, a semiconductor structure includes an epitaxial source feature and an epitaxial drain feature, a vertical stack of channel members disposed over a backside dielectric layer, the vertical stack of channel members extending between the epitaxial source feature and the epitaxial drain feature along a direction, a gate structure wrapping around each of the vertical stack of channel members, and a backside source contact disposed in the backside dielectric layer. The backside source contact includes a top portion adjacent the epitaxial source feature and a bottom portion away from the epitaxial source feature. The top portion and the bottom portion includes a step width change along the direction.

Abstract: A semiconductor structure includes one or more channel layers; a gate structure engaging the one or more channel layers; a first source/drain feature connected to a first side of the one or more channel layers and adjacent to the gate structure; a first dielectric cap disposed over the first source/drain feature, wherein a bottom surface of the first dielectric cap is below a top surface of the gate structure; a via disposed under and electrically connected to the first source/drain feature; and a power rail disposed under and electrically connected to the via.

Abstract: Semiconductor devices and methods of forming the same are provided. In one embodiment, a semiconductor device includes an active region including a channel region and a source/drain region and extending along a first direction, and a source/drain contact structure over the source/drain region. The source/drain contact structure includes a base portion extending lengthwise along a second direction perpendicular to the first direction, and a via portion over the base portion. The via portion tapers away from the base portion.

Abstract: Semiconductor devices and methods of forming the same are provided. In one embodiment, a semiconductor device includes a gate structure sandwiched between and in contact with a first spacer feature and a second spacer feature, a top surface of the first spacer feature and a top surface of the second spacer feature extending above a top surface of the gate structure, a gate self-aligned contact (SAC) dielectric feature over the first spacer feature and the second spacer feature, a contact etch stop layer (CESL) over the gate SAC dielectric feature, a dielectric layer over the CESL, a gate contact feature extending through the dielectric layer, the CESL, the gate SAC dielectric feature, and between the first spacer feature and the second spacer feature to be in contact with the gate structure, and a liner disposed between the first spacer feature and the gate contact feature.

Abstract: A semiconductor nanostructure and an epitaxial semiconductor material portion are formed on a front surface of a substrate, and a planarization dielectric layer is formed thereabove. A first recess cavity is formed over a gate electrode, and a second recess cavity is formed over the epitaxial semiconductor material portion. The second recess cavity is vertically recessed to form a connector via cavity. A metallic cap structure is formed on the gate electrode in the first recess cavity, and a connector via structure is formed in the connector via cavity. Front-side metal interconnect structures are formed on the connector via structure and the metallic cap structure, and a backside via structure is formed through the substrate on the connector via structure.

Abstract: A device includes a substrate, a gate structure over the substrate, a gate spacer on a sidewall of the gate structure, a source/drain (S/D) region adjacent to the gate spacer, a silicide on the S/D region, a dielectric liner over a sidewall of the gate spacer, wherein a bottom surface of the dielectric liner is spaced away from the silicide by a gap, and an S/D contact over the silicide and at least partially filling the gap.

Abstract: A fin field effect transistor device structure includes a fin structure formed over a substrate. The structure also includes a gate structure formed across the fin structure. The structure also includes a cap layer formed over the gate structure. The structure also includes a contact structure formed over the gate structure penetrating through the cap layer. The structure also includes an isolation film formed over sidewalls of the contact structure. The isolation film is separated from the gate structure, and a bottom surface of the isolation film is below a top surface of the cap layer.

Abstract: A semiconductor device structure, along with methods of forming such, are described. The semiconductor device structure includes a device, a conductive structure disposed over the device, and the conductive structure includes a sidewall having a first portion and a second portion. The semiconductor device structure further includes a first spacer layer including a third portion and a fourth portion, the third portion surrounds the first portion of the sidewall, and the fourth portion is disposed on the conductive structure. The semiconductor device structure further includes a first dielectric material surrounding the third portion, and an air gap is formed between the first dielectric material and the third portion of the first spacer layer. The first dielectric material includes a first material different than a second material of the first spacer layer, and the first dielectric material is substantially coplanar with the fourth portion of the first spacer layer.

Abstract: A semiconductor device structure, along with methods of forming such, are described. The semiconductor device structure includes a device, a first conductive structure disposed over the device, and the first conductive structure includes a first sidewall having a first portion and a second portion. The semiconductor device structure further includes a first spacer layer disposed on the first portion, a second conductive structure disposed adjacent the first conductive structure, and the second conductive structure includes a second sidewall having a third portion and a fourth portion. The semiconductor device structure further includes a second spacer layer disposed on the third portion, and an air gap is formed between the first conductive structure and the second conductive structure. The second portion, the first spacer layer, the fourth portion, and the second spacer layer are exposed to the air gap.

Abstract: A semiconductor structure includes a semiconductor substrate, a metallization feature over the semiconductor substrate, a first dielectric feature, a second dielectric feature, and a via contact. The metallization feature includes a first bottom corner and a second bottom corner opposite to the first bottom corner. The first dielectric feature is adjacent to the first bottom corner, and the second dielectric feature is adjacent to the second bottom corner. The metallization feature is interposed between the first dielectric feature and the second dielectric feature. In some embodiments, an included angle of the first bottom corner defined by a sidewall of first dielectric feature and a bottom surface of the metallization feature is less than 90°. The via contact is configured to connect the metallization feature to the semiconductor substrate.

Abstract: Semiconductor devices including air spacers formed in a backside interconnect structure and methods of forming the same are disclosed. In an embodiment, a device includes a first transistor structure; a front-side interconnect structure on a front-side of the first transistor structure; and a backside interconnect structure on a backside of the first transistor structure, the backside interconnect structure including a first dielectric layer on the backside of the first transistor structure; a first via extending through the first dielectric layer, the first via being electrically coupled to a source/drain region of the first transistor structure; a first conductive line electrically coupled to the first via; and an air spacer adjacent the first conductive line in a direction parallel to a backside surface of the first dielectric layer.

Abstract: Semiconductor devices including air spacers formed in a backside interconnect structure and methods of forming the same are disclosed. In an embodiment, a device includes a first transistor structure; a front-side interconnect structure on a front-side of the first transistor structure; and a backside interconnect structure on a backside of the first transistor structure, the backside interconnect structure including a first dielectric layer on the backside of the first transistor structure; a first via extending through the first dielectric layer, the first via being electrically coupled to a first source/drain region of the first transistor structure; a first conductive line electrically coupled to the first via; and an air spacer adjacent the first conductive line, the first conductive line defining a first side boundary of the air spacer.

Abstract: Structures and methods that include a device such as a gate-all-around transistor formed on a frontside and a contact to one terminal of the device from the frontside of the structure and one terminal of the device from the backside of the structure. The backside contact may include selectively etching from the backside a first trench extending to expose a first source/drain structure and a second trench extending to a second source/drain structure. A conductive layer is deposited in the trenches and patterned to form a conductive via to the first source/drain structure.

Abstract: A method and structure directed to providing a source/drain isolation structure includes providing a device having a first source/drain region adjacent to a second source/drain region. A masking layer is deposited between the first and second source/drain regions and over an exposed first part of the second source/drain region. After depositing the masking layer, a first portion of an ILD layer disposed on either side of the masking layer is etched, without substantial etching of the masking layer, to expose a second part of the second source/drain region and to expose the first source/drain region. After etching the first portion of the ILD layer, the masking layer is etched to form an L-shaped masking layer. After forming the L-shaped masking layer, a first metal layer is formed over the exposed first source/drain region and a second metal layer is formed over the exposed second part of the second source/drain region.

Abstract: Semiconductor devices and methods of forming the same are provided. A semiconductor device according to one embodiment includes an active region including a channel region and a source/drain region adjacent the channel region, a gate structure over the channel region of the active region, a source/drain contact over the source/drain region, a dielectric feature over the gate structure and including a lower portion adjacent the gate structure and an upper portion away from the gate structure, and an air gap disposed between the gate structure and the source/drain contact. A first width of the upper portion of the dielectric feature along a first direction is greater than a second width of the lower portion of the dielectric feature along the first direction. The air gap is disposed below the upper portion of the dielectric feature.

Abstract: A semiconductor device structure, along with methods of forming such, are described. The semiconductor device structure includes a device, a first dielectric material disposed over the device, and an opening is formed in the first dielectric material. The semiconductor device structure further includes a conductive structure disposed in the opening, and the conductive structure includes a first sidewall. The semiconductor device structure further includes a surrounding structure disposed in the opening, and the surrounding structure surrounds the first sidewall of the conductive structure. The surrounding structure includes a first spacer layer and a second spacer layer adjacent the first spacer layer. The first spacer layer is separated from the second spacer layer by an air gap.

Abstract: The present disclosure provides a semiconductor structure. The structure includes a semiconductor substrate, a gate stack over a first portion of a top surface of the semiconductor substrate; and a laminated dielectric layer over at least a portion of a top surface of the gate stack. The laminated dielectric layer includes at least a first sublayer and a second sublayer. The first sublayer is formed of a material having a dielectric constant lower than a dielectric constant of a material used to form the second sublayer and the material used to form the second sublayer has an etch selectivity higher than an etch selectivity of the material used to form the first sublayer.