A memory device and a method for forming the same are provided. The method includes forming a plurality of gate structures on a substrate, forming a first spacer on opposite sides of the gate structures, filling a dielectric layer between adjacent first spacers, forming a metal silicide layer on the gate structures, conformally forming a spacer material layer over the metal silicide layer, the first spacer layer and the dielectric layer, and performing an etch back process on the spacer material layer to form a second spacer on opposite sides of the metal silicide layer.

The embodiments described herein are directed to a method for the fabrication of transistors with aluminum-free n-type work function layers as opposed to aluminum-based n-type work function layers. The method includes forming a channel portion disposed between spaced apart source/drain epitaxial layers and forming a gate stack on the channel portion, where forming the gate stack includes depositing a high-k dielectric layer on the channel portion and depositing a p-type work function layer on the dielectric layer. After depositing the p-type work function layer, forming without a vacuum break, an aluminum-free n-type work function layer on the p-type work function layer and depositing a metal on the aluminum-free n-type work function layer. The method further includes depositing an insulating layer to surround the spaced apart source/drain epitaxial layers and the gate stack.

A method is provided for producing a plurality of transistors on a substrate comprising at least two adjacent active areas separated by at least one electrically-isolating area, each transistor of the plurality of transistors including a gate having a silicided portion, and first and second spacers on either side of the gate, the first spacers being located on sides of the gate and the second spacers being located on sides of the first spacers. The method includes forming the gates of the transistors, forming the first spacers, forming the second spacers siliciding the gates so as to form the silicided portions of the gates, and removing the second spacers. The removal of the second spacers takes place during the silicidation of the gates and before the silicided portions are fully formed.

A semiconductor device including a substrate; a gate structure on the substrate; a gate spacer on a sidewall of the gate structure; and a polishing stop pattern on the gate structure and the gate spacer, the polishing stop pattern including a first portion covering an upper surface of the gate structure and an upper surface of the gate spacer; and a second portion extending from the first portion in a vertical direction substantially perpendicular to an upper surface of the substrate, wherein an upper surface of a central portion of the first portion of the polishing stop pattern is higher than an upper surface of an edge portion of the first portion thereof, and the upper surface of the central portion of the first portion of the polishing stop pattern is substantially coplanar with an upper surface of the second portion thereof.

A gate insulating film and a gate electrode of non-single crystalline silicon for forming an nMOS transistor are provided on a silicon substrate. Using the gate electrode as a mask, n-type dopants having a relatively large mass number (70 or more) such as As ions or Sb ions are implanted, to form a source/drain region of the nMOS transistor, whereby the gate electrode is amorphized. Subsequently, a silicon oxide film is provided to cover the gate electrode, at a temperature which is less than the one at which recrystallization of the gate electrode occurs. Thereafter, thermal processing is performed at a temperature of about 1000° C., whereby high compressive residual stress is exerted on the gate electrode, and high tensile stress is applied to a channel region under the gate electrode. As a result, carrier mobility of the nMOS transistor is enhanced.

A exemplary semiconductor device includes a first gate structure overlying a surface of the semiconductor body, the first gate structure being silicided. A second gate structure overlies the surface of the semiconductor body and not being silicided. An oxide layer overlies the second gate structure and extends toward the first gate structure. A silicon nitride region is laterally spaced from the second gate structure and overlies a portion of the oxide layer between the first gate structure and the second gate structure.

A method for forming a semiconductor structure includes: providing a substrate; forming a stacked structure on the substrate; forming a barrier layer on a sidewall of the stacked structure; forming a first dielectric layer covering the barrier layer and the stacked structure; removing a portion of the first dielectric layer to expose an upper portion of the stacked structure; forming a metal layer covering the stacked structure and the first dielectric layer; performing an annealing process to react the metal layer with the stacked structure to form a metal silicide layer at the upper portion of the stacked structure; removing an unreacted portion of the metal layer; removing a portion of the barrier layer to form a recess above the barrier layer; and forming a second dielectric layer covering the metal silicide layer and the first dielectric layer to form air gaps on both sides of the stacked structure.

A method for forming a semiconductor structure includes: providing a substrate; forming a stacked structure on the substrate; forming a barrier layer on a sidewall of the stacked structure; forming a first dielectric layer covering the barrier layer and the stacked structure; removing a portion of the first dielectric layer to expose an upper portion of the stacked structure; forming a metal layer covering the stacked structure and the first dielectric layer; performing an annealing process to react the metal layer with the stacked structure to form a metal silicide layer at the upper portion of the stacked structure; removing an unreacted portion of the metal layer; removing a portion of the barrier layer to form a recess above the barrier layer; and forming a second dielectric layer covering the metal silicide layer and the first dielectric layer to form air gaps on both sides of the stacked structure.

Various embodiments of the present disclosure are directed towards a method for forming a fully silicided (FUSI) gated device, the method including: forming a masking layer onto a gate structure over a substrate, the gate structure comprising a polysilicon layer. Forming a first source region and a first drain region on opposing sides of the gate structure within the substrate, the gate structure is formed before the first source and drain regions. Performing a first removal process to remove a portion of the masking layer and expose an upper surface of the polysilicon layer. The first source and drain regions are formed before the first removal process. Forming a conductive layer directly contacting the upper surface of the polysilicon layer. The conductive layer is formed after the first removal process. Converting the conductive layer and polysilicon layer into a FUSI layer. The FUSI layer is thin and uniform in thickness.

A semiconductor structure and a method for manufacturing the same are provided. The semiconductor structure includes a semiconductor substrate, a silicon-containing gate electrode, and at least two gate silicide strips. The silicon-containing gate electrode is on the semiconductor substrate. The at least two gate silicide strips are on an upper surface of the silicon-containing gate electrode.