Abstract: Devices and structures that include a gate spacer having a gap or void are described along with methods of forming such devices and structures. In accordance with some embodiments, a structure includes a substrate, a gate stack over the substrate, a contact over the substrate, and a spacer disposed laterally between the gate stack and the contact. The spacer includes a first dielectric sidewall portion and a second dielectric sidewall portion. A void is disposed between the first dielectric sidewall portion and the second dielectric sidewall portion.

Abstract: The present disclosure provides a semiconductor structure. The semiconductor structure includes a fin structure on a substrate; a first gate stack and a second gate stack formed on the fin structure; a dielectric material layer disposed on the first and second gate stacks, wherein the dielectric layer includes a first portion disposed on a sidewall of the first gate stack with a first thickness and a second portion disposed on a sidewall of the second gate stack with a second thickness greater than the first thickness; a first gate spacer disposed on the first portion of the dielectric material layer; and a second gate spacer disposed on the second portion of the dielectric material layer.

Abstract: A semiconductor device includes a source/drain feature disposed over a substrate. The source/drain feature includes a first nanowire, a second nanowire disposed over the first nanowire, a cladding layer disposed over the first nanowire and the second nanowire and a spacer layer extending from the first nanowire to the second nanowire. The device also includes a conductive feature disposed directly on the source/drain feature such that the conductive feature physically contacts the cladding layer and the spacer layer.

Abstract: A semiconductor includes a first transistor and a second transistor. The first transistor includes a first and a second epitaxial layer, formed of a first semiconductor material. The second epitaxial layer is disposed over the first epitaxial layer. The first transistor also includes a first gate dielectric layer surrounds the first and second epitaxial layers and extends from a top surface of the first epitaxial layer to a bottom surface of the second epitaxial layer and a first metal gate layer surrounding the first gate dielectric layer. The second transistor includes a third epitaxial layer formed of the first semiconductor material and a fourth epitaxial layer disposed directly on the third epitaxial layer and formed of a second semiconductor. The second transistor also includes a second gate dielectric layer disposed over the third and fourth epitaxial layers and a second metal gate layer disposed over the second gate dielectric layer.

Abstract: A method includes forming a gate stack on a middle portion of s semiconductor fin, and forming a first gate spacer on a sidewall of the gate stack. After the first gate spacer is formed, a template dielectric region is formed to cover the semiconductor fin. The method further includes recessing the template dielectric region. After the recessing, a second gate spacer is formed on the sidewall of the gate stack. The end portion of the semiconductor fin is etched to form a recess in the template dielectric region. A source/drain region is epitaxially grown in the recess.

Abstract: A semiconductor structure includes a substrate, a fin, a bottom capping structure and a top capping structure. The fin disposed on the substrate, the fin has a lower portion and an upper portion extending upwards from the lower portion. The bottom capping structure covers a sidewall of the lower portion of the fin. The top capping structure covers a sidewall of the upper portion of the fin.

Abstract: A device includes a first semiconductor strip, a first gate dielectric encircling the first semiconductor strip, a second semiconductor strip overlapping the first semiconductor strip, and a second gate dielectric encircling the second semiconductor strip. The first gate dielectric contacts the first gate dielectric. A gate electrode has a portion over the second semiconductor strip, and additional portions on opposite sides of the first and the second semiconductor strips and the first and the second gate dielectrics.

Abstract: A method includes forming a first hard mask over a semiconductor substrate, etching the semiconductor substrate to form recesses, with a semiconductor strip located between two neighboring ones of the recesses, forming a second hard mask on sidewalls of the semiconductor strip, performing a first anisotropic etch on the second hard mask to remove horizontal portions of the second hard mask, and performing a second anisotropic etch on the semiconductor substrate using the first hard mask and vertical portions of the second hard mask as an etching mask to extend the recesses down. The method further includes removing the vertical portions of the second hard mask, and forming isolation regions in the recesses. The isolation regions are recessed, and a portion of the semiconductor strip between the isolation regions protrudes higher than the isolation regions to form a semiconductor fin.

Abstract: A semiconductor structure includes a substrate, a fin, a bottom capping structure and a top capping structure. The fin disposed on the substrate, the fin has a lower portion and an upper portion extending upwards from the lower portion. The bottom capping structure covers a sidewall of the lower portion of the fin. The top capping structure covers a sidewall of the upper portion of the fin.

Abstract: A method includes forming a gate stack on a middle portion of s semiconductor fin, and forming a first gate spacer on a sidewall of the gate stack. After the first gate spacer is formed, a template dielectric region is formed to cover the semiconductor fin. The method further includes recessing the template dielectric region. After the recessing, a second gate spacer is formed on the sidewall of the gate stack. The end portion of the semiconductor fin is etched to form a recess in the template dielectric region. A source/drain region is epitaxially grown in the recess.

Abstract: A multi-gate semiconductor device is formed that provides a first fin element extending from a substrate. A gate structure extends over a channel region of the first fin element. The channel region of the first fin element includes a plurality of channel semiconductor layers each surrounded by a portion of the gate structure. A source/drain region of the first fin element is adjacent the gate structure. The source/drain region includes a first semiconductor layer, a dielectric layer over the first semiconductor layer, and a second semiconductor layer over the dielectric layer.

Abstract: The present disclosure provides a semiconductor structure. The semiconductor structure includes a fin structure on a substrate; a first gate stack and a second gate stack formed on the fin structure; a dielectric material layer disposed on the first and second gate stacks, wherein the dielectric layer includes a first portion disposed on a sidewall of the first gate stack with a first thickness and a second portion disposed on a sidewall of the second gate stack with a second thickness greater than the first thickness; a first gate spacer disposed on the first portion of the dielectric material layer; and a second gate spacer disposed on the second portion of the dielectric material layer.

Abstract: A method for fabricating a semiconductor device having a substantially undoped channel region includes forming a plurality of fins extending from a substrate. In various embodiments, each of the plurality of fins includes a portion of a substrate, a portion of a first epitaxial layer on the portion of the substrate, and a portion of a second epitaxial layer on the portion of the first epitaxial layer. The portion of the first epitaxial layer of each of the plurality of fins is oxidized, and a liner layer is formed over each of the plurality of fins. Recessed isolation regions are then formed adjacent to the liner layer. The liner layer may then be etched to expose a residual material portion (e.g., Ge residue) adjacent to a bottom surface of the portion of the second epitaxial layer of each of the plurality of fins, and the residual material portion is removed.

Abstract: The present disclosure provides a method, which includes forming a first fin structure and a second fin structure over a substrate, which has a first trench positioned between the first and second fin structures. The method also includes forming a first dielectric layer within the first trench, recessing the first dielectric layer to expose a portion of the first fin structure, forming a first capping layer over the exposed portion of the first fin structure and the recessed first dielectric layer in the first trench, forming a second dielectric layer over the first capping layer in the first trench while the first capping layer covers the exposed portion of the first fin feature and removing the first capping layer from the first fin structure.

Abstract: Devices and structures that include a gate spacer having a gap or void are described along with methods of forming such devices and structures. In accordance with some embodiments, a structure includes a substrate, a gate stack over the substrate, a contact over the substrate, and a spacer disposed laterally between the gate stack and the contact. The spacer includes a first dielectric sidewall portion and a second dielectric sidewall portion. A void is disposed between the first dielectric sidewall portion and the second dielectric sidewall portion.

Abstract: A multi-gate semiconductor device having a fin element, a gate structure over the fin element, an epitaxial source/drain feature adjacent the fin element; a dielectric spacer interposing the gate structure and the epitaxial source/drain feature.

Abstract: A semiconductor device and methods of forming the same are disclosed. The semiconductor device includes a substrate, first and second source/drain (S/D) regions, a channel between the first and second S/D regions, a gate engaging the channel, and a contact feature connecting to the first S/D region. The contact feature includes first and second contact layers. The first contact layer has a conformal cross-sectional profile and is in contact with the first S/D region on at least two sides thereof. In embodiments, the first contact layer is in direct contact with three or four sides of the first S/D region so as to increase the contact area. The first contact layer includes one of a semiconductor-metal alloy, an III-V semiconductor, and germanium.

Abstract: A device includes a first semiconductor strip, a first gate dielectric encircling the first semiconductor strip, a second semiconductor strip overlapping the first semiconductor strip, and a second gate dielectric encircling the second semiconductor strip. The first gate dielectric contacts the first gate dielectric. A gate electrode has a portion over the second semiconductor strip, and additional portions on opposite sides of the first and the second semiconductor strips and the first and the second gate dielectrics.

Abstract: The present disclosure provides a method, which includes forming a first fin structure and a second fin structure over a substrate, which has a first trench positioned between the first and second fin structures. The method also includes forming a first dielectric layer within the first trench, recessing the first dielectric layer to expose a portion of the first fin structure, forming a first capping layer over the exposed portion of the first fin structure and the recessed first dielectric layer in the first trench, forming a second dielectric layer over the first capping layer in the first trench while the first capping layer covers the exposed portion of the first fin feature and removing the first capping layer from the first fin structure.

Abstract: A method for fabricating a semiconductor device having a substantially undoped channel region includes forming a plurality of fins extending from a substrate. In various embodiments, each of the plurality of fins includes a portion of a substrate, a portion of a first epitaxial layer on the portion of the substrate, and a portion of a second epitaxial layer on the portion of the first epitaxial layer. The portion of the first epitaxial layer of each of the plurality of fins is oxidized, and a liner layer is formed over each of the plurality of fins. Recessed isolation regions are then formed adjacent to the liner layer. The liner layer may then be etched to expose a residual material portion (e.g., Ge residue) adjacent to a bottom surface of the portion of the second epitaxial layer of each of the plurality of fins, and the residual material portion is removed.