A semiconductor device includes a transistor. The transistor includes a gate electrode, a channel layer, a gate dielectric layer, a first source/drain region and a second source/drain region and a first spacer. The channel layer is disposed on the gate electrode. The gate dielectric layer is located between the channel layer and the gate electrode. The first source/drain region and the second source/drain region are disposed on the channel layer at opposite sides of the gate electrode, and at least one of the first and second source/drain regions includes a first portion and a second portion between the first portion and the gate electrode. The first spacer is disposed on the channel layer. The first spacer is disposed on a first sidewall of the second portion of the at least one of the first and second source/drain regions, and the first portion is disposed on the first spacer.

A vertical field-effect transistor includes a substrate comprising a semiconductor material; a first set of fins formed from the semiconductor material and extending vertically with respect to the substrate; and a second set of fins extending vertically with respect to the substrate, wherein ones of the second set of fins abut ones of the first set of fins. The second set of fins comprises a dielectric material.

A semiconductor device is provided. The semiconductor device includes: first, second and third active patterns on a logic cell region of a substrate and are spaced apart from each other in a first direction; first and second gate electrodes, the first gate electrode crossing the first active pattern and the second gate electrode crossing the second active pattern; a first separation pattern provided between the first and second active patterns; a second separation pattern provided between the second and third active patterns; a first gate insulating layer interposed between the first gate electrode and the first active pattern; and a first gate cutting pattern interposed between the first and second gate electrodes, and in contact with a top surface of the first separation pattern. The first separation pattern is wider than the second separation pattern, and the first gate insulating layer extends between the first gate electrode and the first separation pattern, and contacts side and top surfaces of the first separation pattern.

Techniques for forming a metastable phosphorous P-doped silicon Si source drain contacts are provided. In one aspect, a method for forming n-type source and drain contacts includes the steps of: forming a transistor on a substrate; depositing a dielectric over the transistor; forming contact trenches in the dielectric that extend down to source and drain regions of the transistor; forming an epitaxial material in the contact trenches on the source and drain regions; implanting P into the epitaxial material to form an amorphous P-doped layer; and annealing the amorphous P-doped layer under conditions sufficient to form a crystalline P-doped layer having a homogenous phosphorous concentration that is greater than about 1.5×10.sup.21 atoms per cubic centimeter (at./cm.sup.3). Transistor devices are also provided utilizing the present P-doped Si source and drain contacts.

A CFET includes a fin that has a bottom channel portion, a top channel portion, and a channel isolator between the bottom channel portion and the top channel portion. The CFET further includes a source and drain stack that has a bottom source or drain (S/D) region connected to the bottom channel portion, a top S/D region connected to the top channel portion, a source-drain isolator between the bottom S/D region and the top S/D region. The CFET further includes a spacer foot physically connected to a base sidewall portion of the bottom S/D region and a buried S/D contact that is physically connected to an upper sidewall portion of the bottom S/D region. The CFET may further include a common gate around the bottom channel portion, around the top channel portion, and around the channel isolator.

A semiconductor device includes a substrate including an active pattern, a channel pattern on the active pattern and including semiconductor patterns vertically stacked and spaced apart from each other, a source/drain pattern connected to the semiconductor patterns, a gate electrode on the semiconductor patterns and extending in a first direction, and a gate insulating layer between the semiconductor patterns and the gate electrode. A first semiconductor pattern of the semiconductor patterns includes opposite side surfaces in the first direction, and bottom and top surfaces. The gate insulating layer covers the opposite side surfaces, and the bottom and top surfaces and includes a first region on one of the opposite side surfaces of the first semiconductor pattern and a second region on one of the top or bottom surfaces of the first semiconductor pattern, and a thickness of the first region may be greater than a thickness of the second region.

A semiconductor device includes a substrate, active regions extending in a first horizontal direction on the substrate, and including first and second active regions spaced apart from each other in a second horizontal direction perpendicular to the first horizontal direction, and third and fourth active regions spaced apart from each other in the second horizontal direction, first to fourth source/drain regions on the first to fourth active regions, first to fourth contact plugs connected to the first to fourth source/drain regions, a first isolation insulating pattern disposed between the first and second contact plugs, and a second isolation insulating pattern disposed between the third and fourth contact plugs, wherein a first length of the first isolation insulating pattern is smaller than a second length of the second isolation insulating pattern in a vertical direction.

Fin-based well straps are disclosed herein for improving performance of memory arrays, such as static random access memory arrays. An exemplary integrated circuit (IC) device includes a FinFET disposed over a doped region of a first type dopant. The FinFET includes a first fin structure doped with a first dopant concentration of the first type dopant and first source/drain features of a second type dopant. The IC device further includes a fin-based well strap disposed over the doped region of the first type dopant. The fin-based well strap connects the doped region to a voltage. The fin-based well strap includes a second fin structure doped with a second dopant concentration of the first type dopant and second source/drain features of the first type dopant. The second dopant concentration is greater than (for example, at least three times greater than) the first dopant concentration.

Structures and formation methods of a semiconductor device structure are provided. The formation method includes forming a fin structure over a semiconductor substrate and forming a first isolation feature in the fin structure. The formation method also includes forming a second isolation feature over the semiconductor substrate after the formation of the first isolation feature. The fin structure and the first isolation feature protrude from the second isolation feature. The formation method further includes forming gate stacks over the second isolation feature, wherein the gate stacks surround the fin structure and the first isolation feature.

A transistor is disclosed. The transistor includes a first part of a gate above a substrate that has a first width and a second part of the gate above the first part of the gate that is centered with respect to the first part of the gate and that has a second width that is greater than the first width. The first part of the gate and the second part of the gate form a single monolithic T-gate structure.