A method for forming a fin on a substrate comprises patterning and etching a layer of a first semiconductor material to define a strained fin, depositing a layer of a second semiconductor material over the fin, the second semiconductor material operative to maintain the a strain in the strained fin, etching to remove a portion of the second semiconductor material to define a cavity that exposes a portion of the fin, etching to remove the exposed portion of the fin such that the fin is divided into a first segment and a second segment, and depositing an insulator material in the cavity, the insulator material contacting the first segment of the fin and the second segment of the fin.

A semiconductor device is provided. A fin is disposed on a substrate. The fin, including a first material and a second material, includes a first fin area and a second fin area. A gate structure is disposed on the first fin area. A source region is in contact with the second fin area. The first fin area includes the first material at a first concentration, the second fin area includes the first material at a second concentration which is greater than the first concentration.

One aspect of the disclosure relates to and integrated circuit structure and methods of forming the same. The integrated circuit structure may include: a thin gate dielectric device on a substrate, the thin gate dielectric device including: a first interfacial layer over a set of fins within the substrate, wherein the interfacial layer has a thickness of approximately 1.0 nanometers (nm) to approximately 1.2 nm; and a thick gate dielectric device on the substrate adjacent to the thin gate dielectric device, the thick gate dielectric device including: a second interfacial layer over the set of fins within the substrate; and a nitrided oxide layer over the second interfacial layer, wherein the nitrided oxide layer includes a thickness of approximately 3.5 nm to approximately 5.0 nm.

A semiconductor structure having multiple semiconductor-device layers is provided. The semiconductor structure includes a first buried oxide and a first semiconductor device layer fabricated above the first buried oxide. The first semiconductor device layer comprises a patterned top surface. A blanket layer of uniform material composition includes insulator material is fabricated over the patterned top surface. The semiconductor structure further includes a second buried oxide bonded to the blanket layer and a second semiconductor device layer fabricated above the second buried oxide.

A method for forming a semiconductor device includes depositing a dielectric layer over fins formed in a semiconductor substrate. The dielectric layer includes a screen layer over tops of the fins. An etch stop feature is formed on the screen layer. The etch stop feature is patterned down to the screen layer in regions across the device. A dummy gate material formed over the fins is planarized down to the etch stop feature, a dielectric fill between gate structures patterned from the dummy gate material is planarized down to the etch stop feature and a gate conductor is planarized to the etch stop feature.

Techniques for dielectric isolation in bulk nanosheet devices are provided. In one aspect, a method of forming a nanosheet device structure with dielectric isolation includes the steps of: optionally implanting at least one dopant into a top portion of a bulk semiconductor wafer, wherein the at least one dopant is configured to increase an oxidation rate of the top portion of the bulk semiconductor wafer; forming a plurality of nanosheets as a stack on the bulk semiconductor wafer; patterning the nanosheets to form one or more nanowire stacks and one or more trenches between the nanowire stacks; forming spacers covering sidewalls of the nanowire stacks; and oxidizing the top portion of the bulk semiconductor wafer through the trenches, wherein the oxidizing step forms a dielectric isolation region in the top portion of the bulk semiconductor wafer. A nanowire FET and method for formation thereof are also provided.

A transistor includes a substrate having an upper surface, a fin structure protruding from the upper surface of the substrate, an isolation structure over the upper surface of the substrate and surrounding a lower portion of the fin structure, and a first doped region at least partially embedded in an upper portion of the fin structure. The fin structure extends along a first direction. The first doped region has a first type doping different from that of the fin structure.

FinFET devices including III-V fin structures and silicon-based source/drain regions are formed on a semiconductor substrate. Silicon is diffused into the III-V fin structures to form n-type junctions. Leakage through the substrate is addressed by forming p-n junctions adjoining the source/drain regions and isolating the III-V fin structures under the channel regions.

The present disclosure provides an embodiment of a fin-like field-effect transistor (FinFET) device. The device includes a substrate having a first gate region, a first fin structure over the substrate in the first gate region. The first fin structure includes an upper semiconductor material member, a lower semiconductor material member, surrounded by an oxide feature and a liner wrapping around the oxide feature of the lower semiconductor material member, and extending upwards to wrap around a lower portion of the upper semiconductor material member. The device also includes a dielectric layer laterally proximate to an upper portion of the upper semiconductor material member. Therefore the upper semiconductor material member includes a middle portion that is neither laterally proximate to the dielectric layer nor wrapped by the liner.

Embodiments of the present invention provide a structure and method of minimizing stress relaxation during fin formation. Embodiments may involve forming a looped spacer on an upper surface of a substrate and adjacent to at least a sidewall of a mandrel. The mandrel may be removed, leaving the looped spacer on the substrate. An exposed portion of the substrate may be removed to form a looped fin below the looped spacer. The spacer may be removed, leaving a looped fin. A looped fin formation may reduce stress relaxation compared to conventional fin formation methods. Embodiments may include forming a gate over a looped portion of a looped fin. Securing a looped portion in position with a gate may decrease stress relaxation in the fin. Thus, a looped fin with a looped portion of the looped fin under a gate may have substantially reduced stress relaxation compared to a conventional fin.