A method for fabricating a semiconductor structure includes forming a plurality of first fin structures in a core region of a substrate and a plurality of second fin structures in a peripheral region of the substrate, forming a first dummy gate structure including a first dummy gate oxide layer and a first dummy gate electrode layer on each first fin structure and a second dummy gate structure including a second gate oxide layer and a second dummy gate electrode layer on each second fin structure. The method further includes removing each first dummy gate electrode layer, performing an ion implantation process to tune the threshold voltages of the first fin structures, and removing each first dummy gate oxide layer. The method also includes removing each second dummy gate electrode layer, and forming a gate dielectric layer and a metal layer on each first fin structure and each second fin structure.

A method of performing an early PTS implant and forming a buffer layer under a bulk or fin channel to control doping in the channel and the resulting bulk or fin device are provided. Embodiments include forming a recess in a substrate; forming a PTS layer below a bottom surface of the recess; forming a buffer layer on the bottom surface and on side surfaces of the recess; forming a channel layer on and adjacent to the buffer layer; and annealing the channel, buffer, and PTS layers.

A semiconductor structure includes a varactor and a field effect transistor. The varactor includes a body region that includes a semiconductor material and a first gate structure over the body region. The body region is doped to have a first conductivity type. The first gate structure includes a first gate insulation layer and a first work function adjustment metal layer. The field effect transistor includes a source region, a channel region, a drain region and a second gate structure over the channel region. The source region and the drain region are doped to have a second conductivity type that is opposite to the first conductivity type. The second gate structure includes a second gate insulation layer and a second work function adjustment metal layer. The first work function adjustment metal layer and the second work function adjustment metal layer include substantially the same metal.

A method is provided for fabricating a FinFET. The method includes providing a semiconductor substrate; forming a hard mask layer on the semiconductor substrate, wherein a position of the hard mask layer may corresponds to a position of subsequently formed fin; forming a doping region in the semiconductor substrate by using the hard mask layer as a mask to perform an anti-punch-through ion implantation process; forming an anti-punch-through region by performing an annealing process onto the doping region, such that impurity ions in the doping region diffuse into the semiconductor substrate under the hard mask layer; and forming a trench by using the hard mask layer as a mask to etch the semiconductor substrate and the doping region, wherein the semiconductor substrates between the adjacent trenches constitutes a fin.

A fin-type field effect transistor comprising a substrate, a plurality of insulators, at least one gate stack and strained material portions is described. The substrate has a plurality of fins thereon and the fin comprises a stop layer embedded therein. The plurality of insulators is disposed on the substrate and between the plurality of fins. The at least one gate stack is disposed over the plurality of fins and on the plurality of insulators. The strained material portions are disposed on two opposite sides of the at least one gate stack.

A semiconductor device is provided that includes a pedestal of an insulating material present over at least one layer of a semiconductor material, and at least one fin structure in contact with the pedestal of the insulating material. Source and drain region structures are present on opposing sides of the at least one fin structure. At least one of the source and drain region structures includes at least two epitaxial material layers. A first epitaxial material layer is in contact with the at least one layer of semiconductor material. A second epitaxial material layer is in contact with the at least one fin structure. The first epitaxial material layer is separated from the at least one fin structure by the second epitaxial material layer. A gate structure present on the at least one fin structure.

A semiconductor device includes a first active region including at least one first recess; a second active region including at least one second recess; an isolation region including a diffusion barrier that laterally surrounds at least any one active region of the first active region and the second active region; a first recess gate filled in the first recess; and a second recess gate filled in the second recess, wherein the diffusion barrier contacts ends of at least any one of the first recess gate and the second recess gate.

A method for manufacturing a semiconductor device may include the following steps: preparing a semiconductor structure that comprises a substrate and a first fin member, wherein the first fin member is connected to the substrate and comprises a first semiconductor portion; providing a first-type dopant member that directly contacts the first semiconductor portion, comprises first-type dopants, and is at least one of liquid and amorphous; and performing heat treatment on at least one of the first-type dopant member and the first semiconductor portion to enable a first portion of the first-type dopants to diffuse through a first side of the first-type dopant member into the first semiconductor portion.

The present disclosure provides, in accordance with some illustrative embodiments, a method of forming a semiconductor device, the method including providing an SOI substrate with an active semiconductor layer disposed on a buried insulating material layer, which is in turn formed on a base substrate material, forming a gate structure on the active semiconductor layer in an active region of the SOI substrate, partially exposing the base substrate for forming at least one bulk exposed region after the gate structure is formed, and forming a contact structure for contacting the at least one bulk exposed region.

A method of forming a FinFET fin with low-doped and a highly-doped active portions and/or a FinFET fin having tapered sidewalls for Vt tuning and multi-Vt schemes and the resulting device are provided. Embodiments include forming an Si fin, the Si fin having a top active portion and a bottom active portion; forming a hard mask on a top surface of the Si fin; forming an oxide layer on opposite sides of the Si fin; implanting a dopant into the Si fin; recessing the oxide layer to reveal the active top portion of the Si fin; etching the top active portion of the Si fin to form vertical sidewalls; forming a nitride spacer covering each vertical sidewall; recessing the recessed oxide layer to reveal the active bottom portion of the Si fin; and tapering the active bottom portion of the Si fin.