A novel dielectric cap structure for VTFET device fabrication is provided. In one aspect, a method of forming a VTFET device includes: patterning fins in a substrate using fin hardmasks, including a first fin(s) and a second fin(s); depositing a liner over the fins and the fin hardmasks; selectively forming first hardmask caps on top of the fin hardmasks/liner over the first fin(s); forming first bottom source and drain at a base of the first fin(s) while the fin hardmasks/liner over the first fin(s) are preserved by the first hardmask caps; selectively forming second hardmask caps on top of the fin hardmasks/liner over the second fin(s); and forming second bottom source and drains at a base of the second fin(s) while the fin hardmasks/liner over the second fin(s) are preserved by the second hardmask caps. A device structure is also provided.

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 Laterally Diffused Metal Oxide Semiconductor (LDMOS) transistor with implant alignment spacers includes a gate stack comprising a first nitride layer. The first nitride layer is formed on a silicon layer. The gate stack is separated from a substrate by a first oxide layer. The gate stack includes a polysilicon layer formed from the silicon layer, and a second oxide layer is formed on a sidewall of the polysilicon layer. A drain region of the LDMOS transistor is implanted with a first implant aligned to a first edge formed by the second oxide layer. A second nitride layer conformingly covers the second oxide layer. A nitride etch-stop layer conformingly covers the second nitride layer.

A method of fabricating a semiconductor device is described. The method includes forming a nanosheet stack on a substrate, the nanosheet stack includes nanosheet channel layers. A gate is formed around the nanosheet channel layers of the nanosheet stack. A strained material is formed along a sidewall surface of the gate. The strained material is configured to create strain in the nanosheet channel layers of the nanosheet stack.

Self-aligned gate endcap (SAGE) architectures having local interconnects, and methods of fabricating SAGE architectures having local interconnects, are described. In an example, an integrated circuit structure includes a first gate structure over a first semiconductor fin, and a second gate structure over a second semiconductor fin. A gate endcap isolation structure is between the first and second semiconductor fins and laterally between and in contact with the first and second gate structures. A gate plug is over the gate endcap isolation structure and laterally between and in contact with the first and second gate structures. A local gate interconnect is between the gate plug and the gate endcap isolation structure, the local gate interconnect in contact with the first and second gate structures.

A semiconductor device structure includes a dielectric layer, a first source/drain feature in contact with the dielectric layer, wherein the first source/drain feature comprises a first sidewall, and a second source/drain feature in contact with the dielectric layer and adjacent to the first source/drain feature, wherein the second source/drain feature comprises a second sidewall. The structure also includes an insulating layer disposed over the dielectric layer and between the first sidewall and the second sidewall, wherein the insulating layer comprises a first surface facing the first sidewall, a second surface facing the second sidewall, a third surface connecting the first surface and the second surface, and a fourth surface opposite the third surface. The structure includes a sealing material disposed between the first sidewall and the first surface, wherein the sealing material, the first sidewall, the first surface, and the dielectric layer are exposed to an air gap.

The present disclosure describes a method includes forming a fin structure including a fin bottom portion and a stacked fin portion on a substrate. The stacked fin portion includes a first semiconductor layer and a second semiconductor layer, in which the first semiconductor layer includes germanium. The method further includes etching the fin structure to form an opening, delivering a primary etchant and a germanium-containing gas to the fin structure through the opening, and etching a portion of the second semiconductor layer in the opening with the primary etchant and the germanium-containing gas.

A method of fabricating a semiconductor device is described. A plurality of fins is formed over a substrate. Dummy gates are formed patterned over the fins, each dummy gate having a spacer on sidewalls of the patterned dummy gates. Recesses are formed in the fins using the patterned dummy gates as a mask. A passivation layer is formed over the fins and in the recesses in the fins. The passivation layer is patterned to leave a remaining passivation layer only in some of the recesses in the fins. Source and drain regions are epitaxially formed only in the recesses in the fins without the remaining passivation layer.

A method of fabricating a device includes providing a fin having a stack of epitaxial layers including a plurality of semiconductor channel layers interposed by a plurality of dummy layers. A source/drain etch process is performed to remove portions of the stack of epitaxial layers in source/drain regions to form trenches that expose lateral surfaces of the stack of epitaxial layers. A dummy layer recess process is performed to laterally etch the plurality of dummy layers to form recesses along sidewalls of the trenches. An inner spacer material is deposited along sidewalls of the trenches and within the recesses. An inner spacer etch-back process is performed to remove the inner spacer material from the sidewalls of the trenches and to remove a portion of the inner spacer material from within the recesses to form inner spacers having a dish-like region along lateral surfaces of the inner spacers.

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.