A method includes forming a fin structure including a first channel layer, a sacrificial layer, and a second channel layer over a substrate; forming a dummy gate structure across the fin structure; recessing the fin structure; epitaxially growing first source/drain epitaxial structures on opposite sides of the first channel layer; forming first dielectric layers to cover the first source/drain epitaxial structures, respectively; epitaxially growing second source/drain epitaxial structures on opposite sides of the second channel layer; removing the dummy gate structure and the sacrificial layer to form a gate trench between the first source/drain epitaxial structures and between the second source/drain epitaxial structures; and forming a metal gate structure in the gate trench. The second source/drain epitaxial structures are over the first dielectric layers, respectively.

A method includes forming a first transistor in a first wafer, wherein the first transistor includes a first source/drain region, forming a first bond pad electrically coupling to the first source/drain region, forming an second transistor in a second wafer, wherein the second transistor includes a second source/drain region, forming a second bond pad electrically coupling to the second source/drain region, and bonding the second wafer to the first wafer, with the second bond pad being bonded to the first bond pad.

A semiconductor device includes: a substrate; a fin protruding above the substrate; a gate structure over the fin; source/drain regions over the fin and on opposing sides of the gate structure; channel layers over the fin and between the source/drain regions, where the gate structure wraps around the channel layers; and isolation structures under the source/drain regions, where the isolation structures separate the source/drain regions from the fin, where each of the isolation structures includes a liner layer and a dielectric layer over the liner layer, where the dielectric layer has a plurality of sublayers.

Semiconductor structures and methods are provided. A semiconductor structure according to the present disclosure includes a semiconductor substrate, a high-Kappa dielectric layer disposed on the semiconductor substrate, a first plurality of nanostructures disposed over the high-Kappa dielectric layer, a middle dielectric layer disposed over the first plurality of nanostructures, a second plurality of nanostructures over the middle dielectric layer, a first gate structure wrapping around the first plurality of nanostructures, a second gate structure wrapping around the second plurality of nanostructures. The high-Kappa dielectric layer includes metal nitride, metal oxide, silicon carbide, graphene, or diamond.

Semiconductor structures and methods of forming the same are provided. An exemplary method includes depositing a contact etch stop layer (CESL) and an interlayer dielectric (ILD) layer over a bottom epitaxial source/drain feature formed in a bottom portion of a source/drain trench, etching back the CESL and the ILD layer to expose a top portion of the source/drain trench, performing a plasma-enhanced atomic layer deposition process (PEALD) to form an insulating layer over the source/drain trench, where the insulating layer comprises a non-uniform deposition thickness and comprises a first portion in direct contact with the ILD layer and a second portion extending along a sidewall surface of the top portion of the source/drain trench. Method also includes removing the second portion of the insulating layer and forming a top bottom epitaxial source/drain feature on the second portion of the insulating layer and in the source/drain trench.

A method for manufacturing a semiconductor structure includes: forming a channel portion on a fin portion; forming two source/drain portions on the fin portion and at two opposite sides of the channel portion, in which each of the two source/drain portions includes a first semiconductor material that is doped with dopant impurities; and forming two bottom portions each of which is disposed between the fin portion and a corresponding one of the two source/drain portions, in which each of the two bottom portions includes a second semiconductor material that is different from the first semiconductor material and that is capable of trapping the dopant impurities when the dopant impurities in the first semiconductor material diffuse toward the fin portion.

Aspects of the present invention provide a semiconductor structure. The semiconductor structure may include a PFET source/drain (S/D). The PFET S/D may include a silicon germanium (SiGe)-based epi protruding through a BILD plane between a backside interlayer dielectric (BILD) and a first gate, and an NFET S/D. The NFET S/D may include a silicon (Si)-based epi protruding into the BILD plane and a SiGe epi between the BILD and the Si-based.

Disclosed examples include microelectronic devices, e.g. Integrated circuits. One example includes a microelectronic device including a nanosheet lateral drain extended metal oxide semiconductor (LDMOS) transistor with source and drain regions having a first conductivity type extending into a semiconductor substrate having an opposite second conductivity type. A superlattice of alternating layers of nanosheets of a channel region and layers of gate conductor are separated by a gate dielectric, the superlattice extending between the source region and the drain region. A drain drift region of the first conductivity type extends under the drain region and a body region of the second type extends around the source region.

A microelectronic device, e.g. an integrated circuit, includes first and second doped semiconductor regions over a semiconductor substrate. A semiconductor nanosheet layer is connected between the first and second semiconductor regions and has a bandgap greater than 1.5 eV. In some examples such a device is implemented as an LDMOS transistor. A method of forming the device includes forming a trench in a semiconductor substrate having a first conductivity type. A semiconductor nanosheet stack is formed within the trench, the stack including a semiconductor nanosheet layer and a sacrificial layer. Source and drain regions having an opposite second conductivity type are formed extending into the semiconductor nanosheet stack. The sacrificial layer between the source region and the drain region is removed, and the semiconductor nanosheet layer is annealed. A gate dielectric layer is formed on the semiconductor nanosheet layer, and a gate conductor is formed on the gate dielectric layer.

A semiconductor device includes a substrate. An active pattern is on the substrate and extends in a first horizontal direction. First to third nanosheets are sequentially stacked on the active pattern and are spaced apart from each other in a vertical direction. A gate electrode is on the active pattern and extends in a second horizontal direction. The gate electrode surrounds each of the first to third nanosheets. A source/drain region is on the active pattern on at least one side of the gate electrode. An interlayer insulating layer covers the source/drain region. A source/drain contact penetrates the interlayer insulating layer in the vertical direction and is connected to the source/drain region. At least a portion of the interlayer insulating layer is disposed between sidewalls of the source/drain contact and the source/drain region in the first horizontal direction and overlaps sidewalls of the third nanosheet along the first horizontal direction.