A method of manufacturing a semiconductor device includes forming a fin structure comprising alternately stacked first semiconductor layers and second semiconductor layers over a substrate. A sacrificial gate structure is formed over the fin structure. Spacers are formed on either side of the sacrificial gate structure. The sacrificial gate structure is removed to form a trench between the spacers. The first semiconductor layers are removed from the trench, while leaving the second semiconductor layers suspended in the trench. A self-assembling monolayer is formed on sidewalls of the spacers in the trench. Interfacial layers are formed encircling the suspended second semiconductor layers, respectively. A high-k dielectric layer is deposited at a faster deposition rate on the interfacial layers than on the self-assembling monolayer. A metal gate structure is formed over the high-k dielectric layer.

A semiconductor device includes a first active region defined on a substrate, a first gate electrode across the first active region, a first drain region in the first active region at a position adjacent to the first gate electrode, an undercut region between the first active region and the first gate electrode, and a first gate spacer on a side surface of the first gate electrode and extending into the undercut region.

A method of manufacturing a non-volatile memory semiconductor device includes forming a plurality of memory cells on a non-volatile memory cell area of a semiconductor substrate, and forming a conductive layer over the plurality of memory cells. A first planarization layer of a planarization material having a viscosity of less than about 1.2 centipoise is formed over the plurality of memory cells. A planarization operation is performed on the first planarization layer and the conductive layer, thereby removing an upper region of the first planarization layer and an upper region of the conductive layer. Portions of a lower region of the conductive layer are completely removed between the memory cells.

A method includes removing a dummy gate stack to form an opening between gate spacers, selectively forming an inhibitor film on sidewalls of the gate spacers, with the sidewalls of the gate spacers facing the opening, and selectively forming a dielectric layer over a surface of a semiconductor region. The inhibitor film inhibits growth of the dielectric layer on the inhibitor film. The method further includes removing the inhibitor film, and forming a replacement gate electrode in a remaining portion of the opening.

In some embodiments, the present disclosure relates to an integrated circuit. The integrated circuit has a first doped region and a second doped region within a substrate. A ferroelectric material is arranged over the substrate and laterally between the first doped region and the second doped region. A conductive electrode is over the ferroelectric material and between sidewalls of the ferroelectric material. One or more sidewall spacers are arranged along opposing sides of the ferroelectric material. A dielectric layer continuously and laterally extends from directly below the one or more sidewall spacers to directly below the ferroelectric material.

A method for manufacturing a semiconductor device includes steps of forming a protective film on a semiconductor substrate, forming a resist film on the protective film such that the resist film includes a region where the resist film becomes thicker from a drain electrode to a source electrode, forming a first opening in the resist film by irradiating the resist film in the region with an electron beam and developing the resist film, forming a second opening that exposes an upper surface of semiconductor substrate by removing the protective film using the resist film on which the first opening is formed as a mask, forming a third opening in the resist film by further developing the resist film after forming the second opening, the third opening being formed by expanding the first opening toward the drain electrode, and forming a gate electrode in the second and the third openings.

A method may include forming a dummy dielectric layer over a substrate, and forming a dummy gate over the dummy dielectric layer. The method may also include forming a first spacer adjacent the dummy gate, and removing the dummy gate to form a cavity, where the cavity is defined at least in part by the first spacer. The method may also include performing a plasma treatment on portions of the first spacer, where the plasma treatment causes a material composition of the portions of the first spacer to change from a first material composition to a second material composition. The method may also include etching the portions of the first spacer having the second material composition to remove the portions of the first spacer having the second material composition, and filling the cavity with conductive materials to form a gate structure.

A transistor device and method of making the same are disclosed. The transistor device includes one or more air gaps in one or more sidewall spacers. The one or more air gaps may be located adjacent the gate and/or above the source or drain regions of the device. Various embodiments may include different combinations of air gaps formed in one or both sidewall spacers. Various embodiments may include air gaps formed in one or both sidewall spacers adjacent to the gate and/or above the source or drain regions of the device. The formation of the air gaps may reduce unwanted parasitic and/or fringing capacitance.

Methods are provided to construct field-effect transistors comprising low-resistance metallic gate structures. A field-effect transistor includes a nanosheet stack and a metal gate which covers a gate region of the nanosheet stack. The nanosheet stack includes nanosheet channel layers and an etch stop layer disposed above an upper nanosheet channel layer. The metal gate includes a work function metal which encapsulates the nanosheet channel layers, and a gate electrode disposed above and in contact with the work function metal. An upper surface of the work function metal is recessed to be substantially coplanar with the etch stop layer. The gate electrode has a resistivity which is less than a resistivity of the work function metal. The etch stop layer protects the portion of the work function metal disposed between the etch stop layer and the upper nanosheet channel layer from being etched when recessing the work function metal.

Methods are provided to construct field-effect transistors comprising low-resistance metallic gate structures. A field-effect transistor includes a nanosheet stack and a metal gate which covers a gate region of the nanosheet stack. The nanosheet stack includes nanosheet channel layers and an etch stop layer disposed above an upper nanosheet channel layer. The metal gate includes a work function metal which encapsulates the nanosheet channel layers, and a gate electrode disposed above and in contact with the work function metal. An upper surface of the work function metal is recessed to be substantially coplanar with the etch stop layer. The gate electrode has a resistivity which is less than a resistivity of the work function metal. The etch stop layer protects the portion of the work function metal disposed between the etch stop layer and the upper nanosheet channel layer from being etched when recessing the work function metal.