Gate-all-around integrated circuit structures having underlying dopant-diffusion blocking layers are described. For example, an integrated circuit structure includes a vertical arrangement of horizontal nanowires above a fin. The fin includes a dopant diffusion blocking layer on a first semiconductor layer, and a second semiconductor layer on the dopant diffusion blocking layer. A gate stack is around the vertical arrangement of horizontal nanowires. A first epitaxial source or drain structure is at a first end of the vertical arrangement of horizontal nanowires. A second epitaxial source or drain structure is at a second end of the vertical arrangement of horizontal nanowires.

A semiconductor device includes a first channel region disposed over a substrate, a first source region and a first drain region disposed over the substrate and connected to the first channel region such that the first channel region is disposed between the first source region and the first drain region, a gate dielectric layer disposed on and wrapping the first channel region, a gate electrode layer disposed on the gate dielectric layer and wrapping the first channel region, and a second source region and a second drain region disposed over the substrate and below the first source region and the first drain region, respectively. The second source region and the second drain region are in contact with the gate dielectric layer. A lattice constant of the first source region and the first drain region is different from a lattice constant of the second source region and the second drain region.

The present disclosure provides a method of manufacturing a semiconductor device. The method includes steps of providing a patterned mask having a plurality of openings on a substrate; etching the substrate through the openings to form an etched substrate and a trench in the etched substrate, wherein the etched substrate comprises a protrusion; introducing dopants having a first conductivity type in the etched substrate and on either side of the trench to form a plurality of first impurity regions; forming an isolation film in the trench; and depositing a conductive material on the isolation film.

Gate-all-around integrated circuit structures having vertically discrete source or drain structures, and methods of fabricating gate-all-around integrated circuit structures having vertically discrete source or drain structures, are described. For example, an integrated circuit structure includes a vertical arrangement of horizontal nanowires. A gate stack is around the vertical arrangement of horizontal nanowires. A first epitaxial source or drain structure is at a first end of the vertical arrangement of horizontal nanowires, the first epitaxial source or drain structure including vertically discrete portions aligned with the vertical arrangement of horizontal nanowires. A second epitaxial source or drain structure is at a first end of the vertical arrangement of horizontal nanowires, the second epitaxial source or drain structure including vertically discrete portions aligned with the vertical arrangement of horizontal nanowires.

An integrated circuit (IC) structure includes an active device over a bulk semiconductor substrate, and an isolation structure around the active device in the bulk semiconductor substrate. The isolation structure includes: a polycrystalline isolation layer under the active device, a trench isolation adjacent the active device, and a porous semiconductor layer between the trench isolation and the bulk semiconductor substrate.

Integrated circuit structures having partitioned source or drain contact structures, and methods of fabricating integrated circuit structures having partitioned source or drain contact structures, are described. For example, an integrated circuit structure includes a fin. A gate stack is over the fin. A first epitaxial source or drain structure is at a first end of the fin. A second epitaxial source or drain structure is at a second end of the fin. A conductive contact structure is coupled to one of the first or the second epitaxial source or drain structures. The conductive contact structure has a first portion partitioned from a second portion.

Double gate/gate-all-around and variable threshold voltage MOSFET devices and techniques for fabrication thereof in a single backside process are provided. In one aspect, a MOSFET device includes: a channel in between source/drain regions; at least one first gate disposed on a first side of the channel at a frontside of the MOSFET device; gate spacers offsetting the source/drain regions from the at least one first gate; and at least one second gate disposed on a second side of the channel directly opposite the at least one first gate at a backside of the MOSFET device. At least one gate contact can be present in direct contact with the at least one first gate and the at least one second gate. A method of forming a MOSFET device is also provided.

Semiconductor structures and methods for manufacturing the same are provided. The semiconductor structure includes a substrate and first channel structures and second channel structures formed over the substrate. The semiconductor structure also includes a dielectric fin structure formed between the first channel structures and the second channel structures. In addition, the dielectric fin structure includes a core portion and first connecting portions connected to the core portion. The semiconductor structure also includes a gate structure including a first portion. In addition, the first portion of the gate structure is formed around the first channel structures and covers the first connecting portions of the dielectric fin structure.

Making of a transistor structure comprising in this order: forming semiconductor blocks made of Si.sub.xGe.sub.1-x over the surface semiconductor layer and on either side of insulating spacers, the semiconductor blocks having lateral facets, growth of a silicon-based layer over the semiconductor blocks, so as to fill cavities located between said facets and said insulating spacers, thermal oxidation to perform a germanium enrichment of semiconductor portions of the surface semiconductor layer disposed on either side of the spacers.

A semiconductor structure includes a substrate, an insulating layer disposed on the substrate, an active layer disposed on the insulating layer, a first semiconductor device formed in a first device region of the active layer, a charge trap structure through the active layer and surrounding the first device region, and a charge trap layer between the insulating layer and the substrate and extending laterally to underlie the first device region and the charge trap structure.