N-type gate-all-around (nanosheet, nanoribbon, nanowire) field-effect transistors (GAAFETs) vertically stacked on top of p-type GAAFETs in complementary FET (CFET) devices comprise non-crystalline silicon layers that form the n-type transistor source, drain, and channel regions. The non-crystalline silicon layers can be formed via deposition, which can provide for a simplified processing flow to form the middle dielectric layer between the n-type and p-type GAAFETs relative to processing flows where the silicon layers forming the n-type transistor source, drain, and channel regions are grown epitaxially.

A semiconductor device including a contact plug formed in a contact hole using a multi-stage contact etch process. The semiconductor device comprises a source/drain region over a semiconductor substrate, an oxide layer extension extending from the source/drain region toward a gate dielectric layer, and a contact plug extending through a dielectric layer over the source/drain region, the contact plug extending through a first etch stop layer and a second etch stop layer to a horizontal remaining portion of the oxide layer extension.

Semiconductor structures and methods for manufacturing the same are provided. The semiconductor structure includes an isolation structure formed over a substrate, and first nanostructures formed over an isolation structure along a first direction. The semiconductor includes second nanostructures adjacent to the first nanostructure along the first direction. The semiconductor also includes a dielectric wall between the first nanostructures and the second nanostructures, and the dielectric wall includes a low-k dielectric material. The dielectric wall is in direct contact with the first nanostructures and the second nanostructures, and a top surface of the dielectric wall is higher than a top surface of the isolation structure. The semiconductor includes a gate structure formed over the first nanostructures along a second direction, and a cutting structure formed over the dielectric wall. The gate structure is divided into two portions by the cutting structure.

The semiconductor device includes a multi-finger high electron mobility transistor (HEMT). The multi-finger HEMT includes a two-dimensional electron gas (2-DEG); a plurality of source fingers, wherein a first source finger of the plurality of source fingers extends continuously across the 2-DEG, and a second source finger of the plurality of source fingers is discontinuous across the 2-DEG; and a plurality of drain fingers, wherein the plurality of drain fingers is interdigitated with the plurality of source fingers. The second source finger is part of a current sensing element.

An embodiment includes a method including forming an opening in a cut metal gate region of a metal gate structure of a semiconductor device, conformally depositing a first dielectric layer in the opening, conformally depositing a silicon layer over the first dielectric layer, performing an oxidation process on the silicon layer to form a first silicon oxide layer, filling the opening with a second silicon oxide layer, performing a chemical mechanical polishing on the second silicon oxide layer and the first dielectric layer to form a cut metal gate plug, the chemical mechanical polishing exposing the metal gate structure of the semiconductor device, and forming a first contact to a first portion of the metal gate structure and a second contact to a second portion of the metal gate structure, the first portion and the second portion of the metal gate structure being separated by the cut metal gate plug.

An embodiment is a structure including a first fin over a substrate, a second fin over the substrate, the second fin being adjacent the first fin, an isolation region surrounding the first fin and the second fin, a gate structure along sidewalls and over upper surfaces of the first fin and the second fin, the gate structure defining channel regions in the first fin and the second fin, a source/drain region on the first fin and the second fin adjacent the gate structure, and an air gap separating the source/drain region from a top surface of the substrate.

Capacitor cells are provided. A first PMOS transistor is coupled between a power supply and a first node, and has a gate directly connected to a second node. A first NMOS transistor is coupled between a ground and the second node, and has a gate directly connected to the first node. A second PMOS transistor is coupled between the second node and the power supply, and has a gate directly connected to the second node. A second NMOS transistor is coupled between the first node and the ground, and has a gate directly connected to the first node. Sources of the first and second NMOS transistors share an N+ doped region in the P-type well region. The first NMOS transistor is disposed between the second NMOS transistor and the first and second PMOS transistors. Source of the first PMOS transistor is directly connected to the power supply.

Techniques are disclosed herein for creating metal bitlines (BLs) in stacked wafer memory. Using techniques described herein, metal BLs are created on a bottom surface of a wafer. The metal BLs can be created using different processes. In some configurations, a salicide process is utilized. In other configurations, a damascene process is utilized. Using metal reduces the resistance of the BLs as compared to using non-metal diffused BLs. In some configurations, wafers are stacked and bonded together to form three-dimensional memory structures.

A semiconductor device includes an active pattern including a channel region. The channel region is disposed between first and second source/drain patterns that are spaced apart from each other in a first direction. The channel region is configured to connect the first and second source/drain patterns to each other. A gate electrode is disposed on a bottom surface of the active pattern and is disposed between the first and second source/drain patterns. An upper interconnection line is disposed on a top surface of the active pattern opposite to the bottom surface of the active pattern and is connected to the first source/drain pattern.

A method for fabricating a semiconductor device includes the steps of first forming a gate dielectric layer on a substrate, forming a gate material layer on the gate dielectric layer, patterning the gate material layer and the gate dielectric layer to form a gate structure, removing a portion of the gate dielectric layer, forming a spacer adjacent to the gate structure and at the same time forming an air gap between the gate dielectric layer and the spacer, and then forming a source/drain region adjacent to two sides of the spacer.