A method includes removing a first dummy gate stack and a second dummy gate stack to form a first trench and a second trench. The first dummy gate stack and the second dummy gate stack are in a first device region and a second device region, respectively. The method further includes depositing a first gate dielectric layer and a second gate dielectric layer extending into the first trench and the second trench, respectively, forming a fluorine-containing layer comprising a first portion over the first gate dielectric layer, and a second portion over the second gate dielectric layer, removing the second portion, performing an annealing process to diffuse fluorine in the first portion into the first gate dielectric layer, and at a time after the annealing process, forming a first work-function layer and a second work-function layer over the first gate dielectric layer and the second gate dielectric layer, respectively.

A device comprises a substrate, a semiconductor channel over the substrate, and a gate structure over and laterally surrounding the semiconductor channel. The gate structure comprises a first dielectric layer comprising a first dielectric material including dopants. A second dielectric layer is on the first dielectric layer, and comprises a second dielectric material substantially free of the dopants. A metal fill layer is over the second dielectric layer.

The present disclosure provides a method for fabricating a semiconductor structure, including forming a dielectric layer over a first region and a second region of a substrate, wherein the second region is adjacent to the first region, increasing a thickness of the dielectric layer in the first region, including forming an oxygen capturing layer over the dielectric layer in the first region, including forming the oxygen capturing layer over the first region and the second region, and removing the oxygen capturing layer over the second region with a mask layer, performing an oxidizing operation from a top surface of the oxygen capturing layer to increase oxygen concentration of the oxygen capturing layer, removing the oxygen capturing layer over the first region, and forming a gate structure over the dielectric layer.

A semiconductor device includes a first semiconductor layer below a second semiconductor layer; first and second gate dielectric layers surrounding the first and the second semiconductor layers, respectively; and a gate electrode surrounding both the first and the second gate dielectric layers. The first gate dielectric layer has a first top section above the first semiconductor layer and a first bottom section below the first semiconductor layer. The second gate dielectric layer has a second top section above the second semiconductor layer and a second bottom section below the second semiconductor layer. The first top section has a first thickness. The second top section has a second thickness. The second thickness is greater than the first thickness.

A transistor structure is disclosed. The transistor structure includes a dielectric layer that has a thinner portion over a first doped well and a second doped well, and a thicker portion adjacent the thinner portion and over the second doped well. The thicker portion has a height greater than the thinner portion above the doped wells. The transistor includes a first gate structure on the thinner portion and a second gate structure on the thicker portion of the dielectric layer. The transistor may include a third gate structure on the thicker portion.

Two or more types of fin-based transistors having different gate structures and formed on a single integrated circuit are described. The gate structures for each type of transistor are distinguished at least by the thickness or composition of the gate dielectric layer(s) or the composition of the work function metal layer(s) in the gate electrode. Methods are also provided for fabricating an integrated circuit having at least two different types of fin-based transistors, where the transistor types are distinguished by the thickness and composition of the gate dielectric layer(s) and/or the thickness and composition of the work function metal in the gate electrode.

A three-dimensional semiconductor device includes a first substrate; a plurality of first transistors on the first substrate; a second substrate on the plurality of first transistors; a plurality of second transistors on the second substrate; and an interconnection portion electrically connecting the plurality of first transistors and the plurality of second transistors. Each of the plurality of first transistors includes a first gate insulating film on the first substrate and having a first hydrogen content. Each of the plurality of second transistors includes a second gate insulating film on the second substrate and having a second hydrogen content. The second hydrogen content is greater than the first hydrogen content.

A method used in forming an array of vertical transistors comprises forming laterally-spaced vertical projections that project upwardly from a substrate in a vertical cross-section. The vertical projections individually comprise an upper source/drain region, a lower source/drain region, and a channel region vertically there-between. First gate insulator material is formed along opposing sidewalls of the channel region in the vertical cross-section. One of (a) or (b) is formed over opposing sidewalls of the first gate insulator material in the vertical cross-section, where (a): conductive gate lines that are horizontally elongated through the vertical cross-section; and (b): sacrificial placeholder gate lines that are horizontally elongated through the vertical cross-section. The one of the (a) or the (b) laterally overlaps the upper source/drain region and the lower source/drain region. The first gate insulator material has a top that is below a top of the channel region and has a bottom that is above a bottom of the channel region. An upper void space is laterally between the one of the (a) or the (b) and both of the upper source/drain region and the channel region. A lower void space is laterally between the one of the (a) or the (b) and both of the lower source/drain region and the channel region. Second gate insulator material is formed in the upper and lower void spaces. Other embodiments, including structure independent of method, are disclosed.

A method for fabricating a semiconductor device includes the steps of forming a metal gate on a substrate, a spacer around the metal gate, and a first interlayer dielectric (ILD) layer around the spacer, performing a plasma treatment process to transform the spacer into a first bottom portion and a first top portion, performing a cleaning process to remove the first top portion, and forming a second ILD layer on the metal gate and the first ILD layer.

The present disclosure describes a method for forming (i) input/output (I/O) fin field effect transistors (FET) with polysilicon gate electrodes and silicon oxide gate dielectrics integrated and (ii) non-I/O FETs with metal gate electrodes and high-k gate dielectrics. The method includes depositing a silicon oxide layer on a first region of a semiconductor substrate and a high-k dielectric layer on a second region of the semiconductor substrate; depositing a polysilicon layer on the silicon oxide and high-k dielectric layers; patterning the polysilicon layer to form a first polysilicon gate electrode structure on the silicon oxide layer and a second polysilicon gate electrode structure on the high-k dielectric layer, where the first polysilicon gate electrode structure is wider than the second polysilicon gate electrode structure and narrower than the silicon oxide layer. The method further includes replacing the second polysilicon gate electrode structure with a metal gate electrode structure.