Semiconductor structures and methods are provided. A method according to the present disclosure includes forming a first channel member, a second channel member directly over the first channel member, and a third channel member directly over the second channel member, depositing a first metal layer around each of the first channel member, the second channel member, and the third channel member, removing the first metal layer from around the second channel member and the third channel member while the first channel member remains wrapped around by the first metal layer, after the removing of the first metal layer, depositing a second metal layer around the second channel member and the third channel member, removing the second metal layer from around the third channel member, and after the removing of the second metal layer, depositing a third metal layer around the third channel member.

A method for manufacturing a SRAM cell includes forming a first p-well in a semiconductor substrate; forming a first semiconductor fin extending within the first p-well; forming a first mask layer over the first semiconductor fin; patterning the first mask layer to expose a first channel region of the first semiconductor fin, while leaving a second channel region of the first semiconductor fin covered by the first mask layer; with the patterned first mask layer in place, doping the first channel region of the first semiconductor fin with a first dopant; after doping the first channel region of the first semiconductor fin, removing the first mask layer from the second channel region; and forming a first gate structure extending across the first channel region of the first semiconductor fin and a second gate structure extending across the second channel region of the first semiconductor fin.

A semiconductor memory device according to an embodiment, includes a semiconductor pillar extending in a first direction, a first electrode extending in a second direction crossing the first direction, a second electrode provided between the semiconductor pillar and the first electrode, a first insulating film provided between the semiconductor pillar and the second electrode, a second insulating film provided between the first electrode and the second electrode and on two first-direction sides of the first electrode, and a conductive film provided between the second electrode and the second insulating film, the conductive film not contacting the first insulating film.

A method of forming a semiconductor device includes forming a plurality of fins on a substrate, forming a polysilicon gate structure, and replacing the polysilicon gate structure with a metal gate structure. Replacing the polysilicon gate structure includes depositing a work function metal layer over the plurality of fins, forming a metal oxide layer over the work function metal layer, and depositing a first metal layer over the metal oxide layer. A first portion of the metal oxide layer is formed within an area between adjacent fins from among the plurality of fins. An example benefit includes reduced diffusion of unwanted and/or detrimental elements from the first metal layer into its underlying layers and consequently, the reduction of the negative impact of these unwanted and/or detrimental elements on the semiconductor device performance.

A semiconductor device has a semiconductor substrate with a dielectric layer disposed thereon. A trench is defined in the dielectric layer. A metal gate structure is disposed in the trench. The metal gate structure includes a first layer and a second layer disposed on the first layer. The first layer extends to a first height in the trench and the second layer extends to a second height in the trench; the second height is less than the first height.

A method of forming a semiconductor device including forming a fin structure having a stack of alternating first semiconductor layers and second semiconductor layers over a substrate, the first semiconductor layers and the second semiconductor layers having different compositions, forming a dummy gate structure across the fin structure, forming gate spacers on opposite sidewalls of the dummy gate structure, respectively, removing the dummy gate structure to form a gate trench between the gate spacers, etching the first semiconductor layers in the gate trench, such that the second semiconductor layers are suspended in the gate trench to serve as nanosheets, forming a work function metal layer surrounding each of the nanosheets, and depositing a fill metal layer over the work function metal layer without using a fluorine-containing precursor.

A method of fabricating a semiconductor device includes forming a dummy gate structure over a semiconductor fin. The dummy gate structure includes a dummy gate stack and gate spacers along sidewalls of the dummy gate stack. The method further includes forming an inter-layer dielectric (ILD) layer surrounding the dummy gate structure, removing the dummy gate stack to provide an opening exposing a channel region of the semiconductor fin, depositing a gate dielectric layer over bottom and sidewalls of the opening and over the ILD layer, forming a doped work function material layer over the gate dielectric layer using an in-situ doping process, and depositing a gate electrode layer over the doped work function material layer.

In a transistor including an oxide semiconductor layer, an oxide insulating layer is formed so as to be in contact with the oxide semiconductor layer. Then, oxygen is introduced (added) to the oxide semiconductor layer through the oxide insulating layer, and heat treatment is performed. Through these steps of oxygen introduction and heat treatment, impurities such as hydrogen, moisture, a hydroxyl group, or hydride are intentionally removed from the oxide semiconductor layer, so that the oxide semiconductor layer is highly purified.

Apparatus and circuits with dual threshold voltage transistors and methods of fabricating the same are disclosed. In one example, a semiconductor structure is disclosed. The semiconductor structure includes: a substrate; a first layer comprising a first III-V semiconductor material formed over the substrate; a first transistor formed over the first layer, and a second transistor formed over the first layer. The first transistor comprises a first gate structure comprising a first material, a first source region and a first drain region. The second transistor comprises a second gate structure comprising a second material, a second source region and a second drain region. The first material is different from the second material.

A memory stack structure including a memory film and a vertical semiconductor channel can be formed within each memory opening that extends through a stack including an alternating plurality of insulating layers and sacrificial material layers. After formation of backside recesses through removal of the sacrificial material layers selective to the insulating layers, a backside blocking dielectric layer may be formed in the backside recesses and sidewalls of the memory stack structures. A metallic barrier material portion can be formed in each backside recess. A metallic material portion is formed on the metallic barrier material portion. Subsequently, a metal portion comprising a material selected from cobalt and ruthenium is formed directly on a sidewall of the metallic barrier material portion and a sidewall of the metallic material portion and an overlying insulating surface and an underlying insulating surface.