A semiconductor structure includes a field effect transistor (FET) including a first source-drain region, a second source-drain region, a gate between the first and second source-drain regions, and a channel region under the gate and between the first and second source-drain regions. Also included are a front side wiring network, having a plurality of front side wires, on a front side of the field effect transistor; a front side conductive path electrically interconnecting one of the front side wires with the first source-drain region; a back side power rail, on a back side of the FET; and a back side contact electrically interconnecting the back side power rail with the second source-drain region. A dielectric liner and back side dielectric fill are on a back side of the gate adjacent the back side contact, and they electrically confine the back side contact in a cross-gate direction.

A 3D semiconductor device including: a first level including a plurality of first metal layers; a second level, where the second level overlays the first level, where the second level includes at least one single crystal silicon layer, where the second level includes a plurality of transistors, where each transistor of the plurality of transistors includes a single crystal channel, where the second level includes a plurality of second metal layers, where the plurality of second metal layers include interconnections between the transistors of the plurality of transistors, and where the second level is overlaid by a first isolation layer; and a connective path between the plurality of transistors and the plurality of first metal layers, where the connective path includes a via disposed through at least the single crystal silicon layer, and where the via includes contact with at least one of the plurality of transistors.

A 3D semiconductor device including: a first level including a single crystal silicon layer and a plurality of first transistors, the plurality of first transistors each including a single crystal channel; a first metal layer overlaying the plurality of first transistors; a second metal layer overlaying the first metal layer; a third metal layer overlaying the second metal layer; a second level is disposed above the third metal layer, where the second level includes a plurality of second transistors; a fourth metal layer disposed above the second level; and a connective path between the fourth metal layer and either the third metal layer or the second metal layer, where the connective path includes a via disposed through the second level, where the via has a diameter of less than 800 nm and greater than 5 nm, and where at least one of the plurality of second transistors includes a metal gate.

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 described herein may be related to apparatuses, processes, and techniques related to well biasing using a buried power rail (BPR) within a circuit structure. Embodiments include using a silicide material between the BPR and a well, where the silicide material provides ohmic contact between the BPR and the well. Other embodiments may be described and/or claimed.

Embodiments described herein may be related to apparatuses, processes, and techniques related to a transistor structure that includes a buried power rail (BPR) located within the transistor structure at a level below a height of one or more of the fins of the transistor structure. The BPR may be located proximate to a bottom substrate of the transistor structure. In embodiments, the transistor structure includes a protective layer, which can include one or more dielectric layers, above the BPR to protect the BPR during stages of transistor structure manufacture. In embodiments, portions of the protective layer may also be used to constrain epitaxial growth during stages of manufacturing of the transistor structure. Other embodiments may be described and/or claimed.

A semiconductor isolation structure includes a silicon-on-insulator wafer, a first deep trench isolation structure and a second deep trench isolation structure. The silicon-on-insulator wafer includes a semiconductor substrate, a buried insulation layer disposed on the semiconductor substrate, and a semiconductor layer disposed on the buried insulation layer. The semiconductor layer has a functional region. The first deep trench isolation structure penetrates the semiconductor layer and the buried insulation layer, and surrounds the functional region. The second deep trench isolation structure penetrates semiconductor layer and the buried insulation layer, and surrounds the first deep trench isolation structure.

A method of fabricating an integrated circuit includes etching trenches in a first surface of a semiconductor layer. A trench dielectric layer is formed over the first surface and over bottoms and sidewalls of the trenches and a doped polysilicon layer is formed over the trench dielectric layer and within the trenches. The doped polysilicon layer is patterned to form a polysilicon bridge that connects to the polysilicon within the filled trenches and a blanket implant of a first dopant is directed to the polysilicon bridge and to the first surface. The blanket implant forms a contact region extending from the first surface into the semiconductor layer.

In an embodiment, a device includes: a power rail contact; an isolation region on the power rail contact; a first dielectric fin on the isolation region; a second dielectric fin adjacent the isolation region and the power rail contact; a first source/drain region on the second dielectric fin; and a source/drain contact between the first source/drain region and the first dielectric fin, the source/drain contact contacting a top surface of the first source/drain region, a side surface of the first source/drain region, and a top surface of the power rail contact.

The present disclosure provides one embodiment of a semiconductor structure. The semiconductor structure includes a substrate having a front side and a back side; a gate stack formed on the front side of the substrate and disposed on an active region of the substrate; a first source/drain feature formed on the active region and disposed at an edge of the gate stack; a backside power rail formed on the back side of the substrate; and a backside contact feature interposed between the backside power rail and the first source/drain feature, and electrically connecting the backside power rail to the first source/drain feature. The backside contact feature further includes a first silicide layer on the back side of the substrate.