A semiconductor device includes a gate isolation structure on a shallow trench isolation (STI), a first epitaxial layer on one side of the gate isolation structure, a second epitaxial layer on another side of the gate isolation structure, first fin-shaped structures directly under the first epitaxial layer, and second fin-shaped structures directly under the second epitaxial layer, in which the STI surrounds the first fin-shaped structures and the second fin-shaped structures.

Provided are semiconductor and a method for manufacturing semiconductor. The semiconductor structure includes: a substrate and a gate located on the substrate, a source is formed in the substrate on one side of the gate, and a drain is formed in the substrate on another side of the gate; a dielectric layer covering a surface of the gate; a contact structure passing through the dielectric layer and electrically connected to the source or the drain, the contact structure including a stack of a first contact layer and a second contact layer, and in a direction from the source to the drain, a width of the second contact layer being greater than a width of the first contact layer; and an electrical connection layer located at a top surface of the dielectric layer and in contact with part of a top surface of the second contact layer.

Semiconductor devices including air spacers formed in a backside interconnect structure and methods of forming the same are disclosed. In an embodiment, a device includes a first transistor structure; a front-side interconnect structure on a front-side of the first transistor structure; and a backside interconnect structure on a backside of the first transistor structure, the backside interconnect structure including a first dielectric layer on the backside of the first transistor structure; a first via extending through the first dielectric layer, the first via being electrically coupled to a source/drain region of the first transistor structure; a first conductive line electrically coupled to the first via; and an air spacer adjacent the first conductive line in a direction parallel to a backside surface of the first dielectric layer.

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.

Semiconductor device fabrication method is provided. The method includes providing a substrate; forming a first semiconductor layer on the substrate; forming a stack of semiconductor layer structures on the first semiconductor layer, each of the semiconductor layer structures comprising a second semiconductor layer and a third semiconductor layer on the second semiconductor layer, the second and third semiconductor layers having at least a common compound element, and the third semiconductor layer and the first semiconductor layer having a same semiconductor compound; performing an etching process to form a fin structure; performing a selective etching process on the second semiconductor layer to form a first air gap between the first semiconductor layer and the third semiconductor layer and a second air gap between each of adjacent third semiconductor layers in the stack of one or more semiconductor layer structures; and filling the first and second air gaps with an insulator layer.

A device includes a plurality of semiconductor fins extending from a substrate. A plurality of first source/drain regions are epitaxially grown from first regions of the semiconductor fins. Adjacent two of the plurality of first source/drain regions grown from adjacent two of the plurality of semiconductor fins are spaced apart by an isolation dielectric. A gate structure laterally surrounds second regions of the plurality of semiconductor fins above the first regions of the plurality of semiconductor fins. A plurality of second source/drain regions are over third regions of the plurality of semiconductor fins above the second regions of the plurality of semiconductor fins.

A transistor, integrated semiconductor device and methods of making are provided. The transistor includes a dielectric layer having a plurality of dielectric protrusions, a channel layer conformally covering the protrusions of the dielectric layer to form a plurality of trenches between two adjacent dielectric protrusion, a gate layer disposed on the channel layer. The gate layer 106 has a plurality of gate protrusions fitted into the trenches. The transistor also includes active regions aside the gate layer. The active regions are electrically connected to the channel layer.

A semiconductor device includes a first PMOS transistor, a first NMOS transistor, and a second NMOS transistor connected to an output node of the first PMOS and NMOS transistors. The first PMOS transistor includes first nanowires, first source and drain regions on opposite sides of each first nanowire, and a first gate completely surrounding each first nanowire. The first NMOS transistor includes second nanowires, second source and drain regions on opposite sides of each second nanowire, and a second gate extending from the first gate and completely surrounding each second nanowire. The second NMOS transistor includes third nanowires, third source and drain regions on opposite sides of each third nanowire, and a third gate, separated from the first and second gates, and completely surrounding each third nanowire. A number of third nanowires is greater than that of first nanowires. The first and second gates share respective first and second nanowires.

Nanowire structures having non-discrete source and drain regions are described. For example, a semiconductor device includes a plurality of vertically stacked nanowires disposed above a substrate. Each of the nanowires includes a discrete channel region disposed in the nanowire. A gate electrode stack surrounds the plurality of vertically stacked nanowires. A pair of non-discrete source and drain regions is disposed on either side of, and adjoining, the discrete channel regions of the plurality of vertically stacked nanowires.

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.