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.

Semiconductor devices are provided. The semiconductor devices may include a first wire pattern extending in a first direction on a substrate and a second wire pattern on the first wire pattern. The second wire pattern may be spaced apart from the first wire pattern and extends in the first direction. The semiconductor devices may also include a first gate structure at least partially surrounding the first wire pattern and the second wire pattern, a second gate structure spaced apart from the first gate structure in the first direction, a first source/drain region between the first gate structure and the second gate structure, a first spacer between a bottom surface of the first source/drain region and the substrate, a first source/drain contact on the first source/drain region, and a second spacer between the first source/drain contact and the first gate structure.

A semiconductor device (1) according to an embodiment includes: a semiconductor substrate; a first well (15) formed on the semiconductor substrate; a second well (15) formed on the semiconductor substrate; first fins (11) formed in the first well; second fins (21) formed in the second well; and a first electrode (12a) connected to each of the first and second fins. The first well and the first fins (11) have the same conductivity type, and the second well and the second fins (21) have different conductivity types.

A semiconductor structure includes a substrate, first fins extending from the substrate with a first fin pitch, and second fins extending from the substrate with a second fin pitch smaller than the first fin pitch. The semiconductor structure also includes first gate structures engaging the first fins with a first gate pitch and second gate structures engaging the second fins with a second gate pitch smaller than the first gate pitch. The semiconductor structure also includes first epitaxial semiconductor features partially embedded in the first fins and adjacent the first gate structures and second epitaxial semiconductor features partially embedded in the second fins and adjacent the second gate structures. A bottom surface of the first epitaxial semiconductor features is lower than a bottom surface of the second epitaxial semiconductor features.

Semiconductor devices and fabrication methods thereof are provided. An exemplary fabrication method includes forming an interlayer dielectric layer on a base substrate; forming a plurality of first openings and second openings in the interlayer dielectric layer, one first opening connecting to a second opening, the one first opening being between the second opening and the base substrate; forming a high-K gate dielectric layer on side and bottom surfaces of the first openings and on side surfaces of the second openings; forming a cap layer, containing oxygen ions, on the high-K gate dielectric layer; forming an amorphous silicon layer on the cap layer at least on the bottoms of the first openings; performing a thermal annealing process on the amorphous silicon layer, the cap layer and the high-K dielectric; removing the amorphous silicon layer; and forming a metal layer, in the first openings and the second openings.

The present disclosure provides semiconductor structures and fabrication methods thereof. An exemplary fabrication method includes providing a plurality of fins on a semiconductor substrate; forming an anti-diffusion layer, containing anti-diffusion ions, in the fins; forming an anti-punch through layer, containing anti-punch through ions, in the fins, a top surface of the anti-punch through layer being below a top surface of the anti-diffusion layer, and the anti-diffusion layer preventing the anti-punch through ions from diffusing toward tops of the fins; and performing a thermal annealing process.

A method for fabricating a semiconductor structure includes providing a base structure including a substrate, a dielectric layer formed on the substrate, a plurality of first openings formed in the dielectric layer in a first transistor region, and a plurality of second openings formed in the dielectric layer in a second transistor region. The method also includes forming a first work function layer an the dielectric layer covering bottom and sidewall surfaces of the first and the second openings, forming a first sacrificial layer in each first opening and each second opening with a top surface lower than the top surface of the dielectric layer, removing a portion of the first work function layer exposed by the first sacrificial layer, removing the first work function layer formed in each first opening, and forming a second work function layer and a gate electrode in each first opening and each second opening.

A semiconductor device includes a substrate having a first region and a second region, first and second nanowires disposed sequentially on the substrate in the first region, and extending respectively in a first direction, third and fourth nanowires disposed sequentially on the substrate in the second region, and extending respectively in the first direction, a first inner spacer between the first nanowire and the second nanowire, and including hydrogen of a first hydrogen mole fraction, and a second inner spacer between the third nanowire and the fourth nanowire, and including hydrogen of a second hydrogen mole fraction that is greater than the first hydrogen mole fraction.

A semiconductor structure includes an isolation structure, a source or drain region over the isolation structure, a channel layer connecting to the source or drain region, a gate structure over the isolation structure and engaging the channel layer, an isolating layer below the channel layer and the gate structure, a dielectric cap below the isolating layer, and a contact structure having a first portion and a second portion. The first portion of the contact structure extends through the isolation structure, and the second portion of the contact structure extends from the first portion of the contact structure, through the dielectric cap and the isolating layer, and to the source or drain region. The first portion of the contact structure is below the second portion and wider than the second portion.

6T-SRAM cell designs for larger SRAM arrays and methods of manufacture generally include a single fin device for both nFET (pass-gate (PG) and pull-down (PD)) and pFET (pull-up (PU). The pFET can be configured with a smaller effective channel width (Weff) than the nFET or with a smaller active fin height. An SRAM big cell consumes the (111) 6t-SRAM design area while provide different Weff ratios other than 1:1 for PU/PD or PU/PG as can be desired for different SRAM designs.