A method for forming semiconductor devices includes forming a highly doped region. A stack of alternating layers is formed on the substrate. The stack is patterned to form nanosheet structures. A dummy gate structure is formed over and between the nanosheet structures. An interlevel dielectric layer is formed. The dummy gate structures are removed. SG regions are blocked, and top sheets are removed from the nanosheet structures along the dummy gate trench. A bottommost sheet is released and forms a channel for a field effect transistor device by etching away the highly doped region under the nanosheet structure and layers in contact with the bottommost sheet. A gate structure is formed in and over the dummy gate trench wherein the bottommost sheet forms a device channel for the EG device.

A method includes forming an isolation region extending into a semiconductor substrate, etching a top portion of the isolation region to form a recess in the isolation region, and forming a gate stack extending into the recess and overlapping a lower portion of the isolation region. A source region and a drain region are formed on opposite sides of the gate stack. The gate stack, the source region, and the drain region are parts of a Metal-Oxide-Semiconductor (MOS) device.

In a method of manufacturing a semiconductor device, a dummy gate structure is formed over a substrate. A first insulating layer is formed over the dummy gate structure. The dummy gate structure is removed so as to form a gate space in the first insulating layer. A first conductive layer is formed in the gate space so as to form a reduced gate space. The reduced gate space is filled with a second conductive layer made of a different material from the first conductive layer. The filled first conductive layer and the second conductive layer are recessed so as to form a first gate recess. A third conductive layer is formed over the first conductive layer and the second conductive layer in the first gate recess. After recessing the filled first conductive layer and the second conductive layer, the second conductive layer protrudes from the first conductive layer.

A method forms first and second sets of fins. The first set includes a first stack of layer pairs where each layer pair contains a layer of Si having a first thickness and a layer of SiGe having a second thickness. The second set of fins includes a second stack of layer pairs where at least one layer pair contains a layer of Si having the first thickness and a layer of SiGe having a third thickness greater than the second thickness. The method further includes removing the layers of SiGe from the first stack leaving first stacked Si nanowires spaced apart by a first distance and from the second stack leaving second stacked Si nanowires spaced apart by a second distance corresponding to the third thickness. The method further includes forming a first dielectric layer on the first nanowires and a second, thicker dielectric layer on the second nanowires.

A semiconductor device includes a first gate structure, a second gate structure, a first source/drain structure and a second source/drain structure. The first gate structure includes a first gate electrode and a first cap insulating layer disposed on the first gate electrode. The second gate structure includes a second gate electrode and a first conductive contact layer disposed on the first gate electrode. The first source/drain structure includes a first source/drain conductive layer and a second cap insulating layer disposed over the first source/drain conductive layer. The second source/drain structure includes a second source/drain conductive layer and a second conductive contact layer disposed over the second source/drain conductive layer.

First, second, and third trenches are formed in a layer over a substrate. The third trench is substantially wider than the first and second trenches. The first, second, and third trenches are partially filled with a first conductive material. A first anti-reflective material is coated over the first, second, and third trenches. The first anti-reflective material has a first surface topography variation. A first etch-back process is performed to partially remove the first anti-reflective material. Thereafter, a second anti-reflective material is coated over the first anti-reflective material. The second anti-reflective material has a second surface topography variation that is smaller than the first surface topography variation. A second etch-back process is performed to at least partially remove the second anti-reflective material in the first and second trenches. Thereafter, the first conductive material is partially removed in the first and second trenches.

A semiconductor device including a substrate including a first and second region; a first active region formed in an upper portion of the substrate in the first region; a second active region formed in an upper portion of the substrate in the second region; a first gate structure extending across the first active region, having a first gate length, and including a first high-k dielectric layer, a first lower metal layer, and a first upper metal layer; a second gate structure extending across the second active region, having a second gate length, and including a second high-k dielectric layer, a second lower metal layer having at least one metal layer, and a second upper metal layer; and spacers at sides of each of the first and second gate structures, a cross section of each of the first and second high-k dielectric layers has a U-shape, a cross section of each of the first and second lower metal layers has a U-shape, the first and second lower metal layers covering bottom surfaces and inner side surfaces of the corresponding first and second high-k dielectric layers, respectively, the first high-k dielectric and first lower metal layer are buried under the first upper metal layer, and the second high-k dielectric and second lower metal layer are buried under the second upper metal layer.

A semiconductor structure includes a substrate, a first power device and a second power device in the substrate, at least one isolation feature between the first and second power device, and a trapping feature adjoining the at least one isolation feature in the substrate.

A method for fabricating a semiconductor structure is provided that includes the steps of: forming a structure including a substrate, a counter-doped layer on the substrate, and a heavily doped source contact layer on a side of the counter-doped layer opposite the substrate; and forming an oxide layer on a side of the heavily doped source contact layer opposite the counter-doped layer, wherein the oxide layer has a vertical dimension that is a difference between a length of a long channel thick oxide device and a length of a short channel non-thick oxide device.

A method for fabricating a semiconductor structure is provided that includes the steps of: forming a structure including a substrate, a counter-doped layer on the substrate, and a heavily doped source contact layer on a side of the counter-doped layer opposite the substrate; and forming an oxide layer on a side of the heavily doped source contact layer opposite the counter-doped layer, wherein the oxide layer has a vertical dimension that is a difference between a length of a long channel thick oxide device and a length of a short channel non-thick oxide device.