Source and drain contacts that provide improved contact resistance and contact interface stability for transistors employing silicon and germanium source and drain materials, related transistor structures, integrated circuits, systems, and methods of fabrication are disclosed. Such source and drain contacts include a contact layer of co-deposited titanium and silicon on the silicon and germanium source and drain. The disclosed source and drain contacts improve transistor performance including switching speed and reliability.

Embodiments disclosed herein include semiconductor devices with improved contact resistances. In an embodiment, a semiconductor device comprises a semiconductor channel, a gate stack over the semiconductor channel, a source region on a first end of the semiconductor channel, a drain region on a second end of the semiconductor channel, and contacts over the source region and the drain region. In an embodiment, the contacts comprise a silicon germanium layer, an interface layer over the silicon germanium layer, and a titanium layer over the interface layer.

Embodiments disclosed herein include semiconductor devices with improved contact resistances. In an embodiment, a semiconductor device comprises a semiconductor channel, a gate stack over the semiconductor channel, a source region on a first end of the semiconductor channel, a drain region on a second end of the semiconductor channel, and contacts over the source region and the drain region. In an embodiment, the contacts comprise a silicon germanium layer, an interface layer over the silicon germanium layer, and a titanium layer over the interface layer.

Disclosed are a semiconductor device and a method of fabricating the same, the semiconductor device including an active pattern on a substrate, a source/drain pattern on the active pattern, a channel pattern on the active pattern, connected to the source/drain pattern, and including stacked semiconductor patterns, a gate electrode extending in a first direction and crossing the channel pattern, and a gate insulating layer between the gate electrode and the channel pattern. The source/drain pattern includes first and second semiconductor layers, the first semiconductor layer including a center portion including a second outer side surface in contact with the gate insulating layer and an edge portion adjacent to a side of the center portion and including a first outer side surface in contact with the gate insulating layer. The second outer side surface is further recessed toward the second semiconductor layer, compared with the first outer side surface.

A semiconductor device is provided. A semiconductor device comprising a first active pattern including a first lower pattern and a plurality of first sheet patterns spaced apart from the first lower pattern in a first direction and having a first source/drain recess formed therein, a first source/drain pattern filling the first source/drain recess and in contact with the first sheet patterns on the first lower pattern, and first gate structures disposed on both sides of the first source/drain pattern in a second direction different from the first direction and each including first gate electrodes each surrounding the plurality of first sheet patterns, wherein the first source/drain pattern includes a first region on the first lower pattern, second regions including impurities of a conductivity type different from that of the first region and in contact with the first region and side surfaces of the first sheet patterns, and a third region between the second regions, and a thickness of the first region in the first direction is greater than a thickness of the second region.

Techniques related to forming selective gate spacers for semiconductor devices and transistor structures and devices formed using such techniques are discussed. Such techniques include forming a blocking material on a semiconductor fin, disposing a gate having a different surface chemistry than the blocking material on a portion of the blocking material, forming a selective conformal layer on the gate but not on a portion of the blocking material, and removing exposed portions of the blocking material.

Semiconductor structures including active fin structures, dummy fin structures, epitaxy layers, a Ge containing oxide layer and methods of manufacture thereof are described. By implementing the Ge containing oxide layer on the surface of the epitaxy layers formed on the source/drain regions of some of the FinFET devices, a self-aligned epitaxy process is enabled. By implementing dummy fin structures and a self-aligned etch, both the epitaxy layers and metal gate structures from adjacent FinFET devices are isolated in a self-aligned manner.

Semiconductor structures including active fin structures, dummy fin structures, epitaxy layers, a Ge containing oxide layer and methods of manufacture thereof are described. By implementing the Ge containing oxide layer on the surface of the epitaxy layers formed on the source/drain regions of some of the FinFET devices, a self-aligned epitaxy process is enabled. By implementing dummy fin structures and a self-aligned etch, both the epitaxy layers and metal gate structures from adjacent FinFET devices are isolated in a self-aligned manner.

A semiconductor structure is provided. The semiconductor structure includes a gate structure, a first source/drain structure, and a contact structure. The gate structure has a gate dielectric layer over a first fin structure. The first source/drain structure is positioned in the first fin structure and adjacent to the gate structure. The first source/drain structure includes a first epitaxial layer in contact with the top surface of the first fin structure and a second epitaxial layer over the first epitaxial layer and extending above a bottom surface of the gate dielectric layer. The contact structure extends into the first source/drain structure. The top surface of the first fin structure is between a top surface and a bottom surface of the first source/drain structure.

A method includes forming a semiconductor structure. The structure includes a first material, a blocking material, a second material in an amorphous form, and a third material in an amorphous form. The blocking material is disposed between the first material and the second material. At least the second material and the third material each comprise silicon and/or germanium. The structure is exposed to a temperature above a crystallization temperature of the third material and below a crystallization temperature of the second material. Semiconductor structures, memory devices, and systems are also disclosed.