A semiconductor device is provided in the disclosure, including a substrate, multiple parallel fins protruding from the substrate and isolated by trenches, and a device insulating layer on the trenches between two fins, wherein the trench is provided with a central first trench and two second trenches at both sides of the first trench, and a depth of the first trench is deeper than a depth of the second trench, and the device insulating layer is provided with a top plane, a first trench and a second trench, and the fins protrude from the top plane, and the bottom surface of the second trench is lower than the bottom surface of the first trench.

Techniques are disclosed for non-planar transistors having varying channel widths (Wsi). In some instances, the resulting structure has a fin (or nanowires, nanoribbons, or nanosheets) comprising a first channel region and a second channel region, with a source or drain region between the first channel region and the second channel region. The widths of the respective channel regions are independent of each other, e.g., a first width of the first channel region is different from a second width of the second channel region. The variation in width of a given fin structure may vary in a symmetric fashion or an asymmetric fashion. In an embodiment, a spacer-based forming approach is utilized that allows for abrupt changes in width along a given fin. Sub-resolution fin dimensions are achievable as well.

A semiconductor device includes a first semiconductor fin, a first epitaxial layer, a first alloy layer and a contact plug. The first semiconductor fin is on a substrate. The first epitaxial layer is on the first semiconductor fin. The first alloy layer is on the first epitaxial layer. The first alloy layer is made of one or more Group IV elements and one or more metal elements, and the first alloy layer comprises a first sidewall and a second sidewall extending downwardly from a bottom of the first sidewall along a direction non-parallel to the first sidewall. The contact plug is in contact with the first and second sidewalls of the first alloy layer.

Methods and apparatus to form silicon-based transistors on group III-nitride materials using aspect ratio trapping are disclosed. An example integrated circuit includes a group III-nitride substrate and a fin of silicon formed on the group III-nitride substrate. The integrated circuit further includes a first transistor formed on the fin of silicon and a second transistor formed on the group III-nitride substrate.

A method includes forming an n-type Fin-Field Effect Transistor (FinFET) and a p-type FinFET. The forming of the n-type FinFFT includes: forming a first auxiliary gate stack over a first semiconductor fin; forming an n-type source/drain region on the first semiconductor fin adjacent to the first auxiliary gate stack; and performing a first etch to form a first recess with a first depth on a first top surface of the n-type source/drain region. The forming of the p-type FinFFT includes: forming a second auxiliary gate stack over a second semiconductor fin; forming a p-type source/drain region on the second semiconductor fin adjacent to the second auxiliary gate stack; and performing a second etch to form a second recess with a second depth on a second top surface of the p-type source/drain region. The first depth is greater than the second depth.

The method for forming a semiconductor device includes forming gate spacers on a substrate; forming a gate structure on the substrate and laterally between the gate spacers; forming a protective cap over the gate structure and laterally between the gate spacers; forming source/drain structures over the substrate and on opposite sides of the gate structure; depositing a dielectric layer over the protective cap, the gate spacers, and the source/drain structures; performing an etching process on the dielectric layer to form an opening exposing one of the source/drain structures, the etching process further etching a first one of the gate spacers to expose the protective cap; selectively depositing a capping material on the exposed protective cap; forming a source/drain contact in the opening.

A semiconductor device includes a semiconductor fin structure extending in a first direction on a substrate and a first dielectric fin structure extending parallel to the fin structure, the first dielectric fin structure being underneath a gate structure extending in a second direction that is perpendicular to the first direction. The device further includes a second dielectric fin structure extending parallel to the fin structure, the second dielectric feature being positioned beneath a gate cut feature. A top surface of the first dielectric fin structure is higher than a top surface of the second dielectric fin structure.

A semiconductor structure according to the present disclosure includes a circuit region disposed over a substrate and a seal ring region disposed over the substrate and completely surrounding the circuit region. The circuit region includes first fins, second fins, n-type epitaxial structures over the first fins, and p-type epitaxial structures over the second fins. The seal ring region includes fin rings extending completely around the circuit region, epitaxial rings disposed over and extending parallel to the fin rings. All of the epitaxial rings over all of the fin rings in the seal ring region are p-type epitaxial rings.

A technique relates to a semiconductor device. A source/drain layer is formed. Fins with gate stacks are formed in a fill material, a dummy fin template including at least one fin of the fins and at least one gate stack of the gate stacks, the fins being formed on the source/drain layer. A trench is formed through the fill material by removing the dummy fin template, such that a portion of the source/drain layer is exposed in the trench. A source/drain metal contact is formed on the portion of the source/drain layer in the trench.

Methods are presented for forming multi-threshold field effect transistors. The methods generally include depositing and patterning an organic planarizing layer to protect underlying structures formed in a selected one of the nFET region and the pFET region of a semiconductor wafer. In the other one of the nFET region and the pFET region, structures are processed to form an undercut in the organic planarizing layer. The organic planarizing layer is subjected to a reflow process to fill the undercut. The methods are effective to protect a boundary between the nFET region and the pFET region.