The present disclosure provides a semiconductor structure. The semiconductor structure includes a substrate including a well region and an adjustment region over the well region. An isolation structure is disposed over the substrate and at least partially surrounds the well region and the adjustment region. An epitaxial layer is disposed over the adjustment region and surrounded by the isolation structure. A gate structure is disposed on the epitaxial layer. The present disclosure also provides a method for forming a semiconductor structure.

A method of production of a field-effect transistor from a stack of layers forming a semiconductor-on-insulator type substrate, the stack including a superficial layer of an initial thickness, made of a crystalline semiconductor material and covered with a protective layer, the method including: defining, by photolithography, a gate pattern in the protective layer; etching the gate pattern into the superficial layer to leave a thickness of the layer of semiconductor material in place, the thickness defining a height of a conduction channel of the field-effect transistor; forming a gate in the gate pattern; forming, in the superficial layer and on either side of the gate, source and drain zones, while preserving, in the zones, the initial thickness of the superficial layer.

Integrated circuits and methods for fabricating integrated circuits are provided. An exemplary method for fabricating an integrated circuit includes providing a substrate including a semiconductor layer over an insulator layer. The method includes selectively replacing portions of the semiconductor layer with insulator material to define an isolated semiconductor layer region. Further, the method includes selectively forming a relaxed layer on the isolated semiconductor layer region. Also, the method includes selectively forming a strained layer on the relaxed layer. The method forms a device over the strained layer.

An integrated circuit structure may include a transistor on a front-side semiconductor layer supported by an isolation layer. The transistor is a first source/drain/body region. The integrated circuit structure may also include a raised source/drain/body region coupled to a backside of the first source/drain/body region of the transistor. The transistor is a raised source/drain/body region extending from the backside of the first source/drain/body region toward a backside dielectric layer supporting the isolation layer. The integrated circuit structure may further include a backside metallization coupled to the raised source/drain/body region.

A chip includes a semiconductor substrate, a well region in the semiconductor substrate, and a Dynamic Threshold Metal-Oxide Semiconductor (DTMOS) transistor formed at a front side of the semiconductor substrate. The DTMOS transistor includes a gate electrode, and a source/drain region adjacent to the gate electrode. The source/drain region is disposed in the well region. A well pickup region is in the well region, and the well pickup region is at a back side of the semiconductor substrate. The well pickup region is electrically connected to the gate electrode.

A semiconductor device includes a semiconductor substrate having a first region and a second region. The first region includes a first set of fin structures, the first set of fin structures comprising a first set of epitaxial anti-punch-through features of a first conductivity type. The first region further includes a first set of transistors formed over the first set of fin structures. The second region includes a second set of fin structures, the second set of fin structures comprising a second set of epitaxial anti-punch-through features of a second conductivity type opposite to the first conductivity type. The second region further includes a second set of transistors formed over the second set of fin structures. The first set of epitaxial anti-punch-through features and the second set of epitaxial anti-punch-through features are substantially co-planar.

Transistors having partially recessed gates are constructed on silicon-on-insulator (SOI) semiconductor wafers provided with a buried oxide layer (BOX), for example, FD-SOI and UTBB devices. An epitaxially grown channel region relaxes constraints on the design of doped source and drain profiles. Formation of a partially recessed gate and raised epitaxial source and drain regions allow further improvements in transistor performance and reduction of short channel effects such as drain induced barrier lowering (DIBL) and control of a characteristic subthreshold slope. Gate recess can be varied to place the channel at different depths relative to the dopant profile, assisted by advanced process control. The partially recessed gate has an associated high-k gate dielectric that is initially formed in contact with three sides of the gate. Subsequent removal of the high-k sidewalls and substitution of a lower-k silicon nitride encapsulant lowers capacitance between the gate and the source and drain regions.

A transistor includes a bulk semiconductor substrate, and a first source/drain region in the bulk semiconductor substrate separated from a second source/drain region in the bulk semiconductor substrate by a channel region. A first air gap is defined in the bulk semiconductor substrate under the first source/drain region, and a second air gap is defined in the bulk semiconductor substrate under the second source/drain region. A gate is over the channel region. A spacing between the first air gap and the second air gap is greater than or equal to a length of the channel region such that the first and second air gaps are not under the channel region. The air gaps may have a rectangular cross-sectional shape. The air gaps reduce off capacitance of the bulk semiconductor structure to near semiconductor-on-insulator levels without the disadvantages of an air gap under the channel region.

A semiconductor device includes at least one active pattern on a substrate, at least one gate electrode intersecting the at least one active pattern, source/drain regions on the at least one active pattern, the source/drain regions being on opposite sides of the at least one gate electrode, and a barrier layer between at least one of the source/drain regions and the at least one active pattern, the barrier layer being at least on bottoms of the source/drain regions and including oxygen.

A semiconductor device includes at least one active pattern on a substrate, at least one gate electrode intersecting the at least one active pattern, source/drain regions on the at least one active pattern, the source/drain regions being on opposite sides of the at least one gate electrode, and a barrier layer between at least one of the source/drain regions and the at least one active pattern, the barrier layer being at least on bottoms of the source/drain regions and including oxygen.