A method forming a gate dielectric over a substrate, and forming a metal gate structure over the semiconductor substrate and the gate dielectric. The metal gate structure includes a first metal material. The method further includes forming a seal on sidewalls of the metal gate structure. The method further includes forming a dielectric film on the metal gate structure, the dielectric film including a first metal oxynitride comprising the first metal material and directly on the metal gate structure without extending over the seal formed on sidewalls of the metal gate structure.

A method for selectively depositing a metallic film on a substrate comprising a first dielectric surface and a second metallic surface is disclosed. The method may include, exposing the substrate to a passivating agent, performing a surface treatment on the second metallic surface, and selectively depositing the metallic film on the first dielectric surface relative to the second metallic surface. Semiconductor device structures including a metallic film selectively deposited by the methods of the disclosure are also disclosed.

Semiconductor devices include vertically stacked channel layers formed from a semiconductor material. A metallic interface layer is formed between metal source/drain regions and the vertically stacked channel layers. The metallic interface layer includes the semiconductor material and a metal. A gate stack is formed between and around the channel layers.

A transistor comprises a substrate, a pair of spacers on the substrate, a gate dielectric layer on the substrate and between the pair of spacers, a gate electrode layer on the gate dielectric layer and between the pair of spacers, an insulating cap layer on the gate electrode layer and between the pair of spacers, and a pair of diffusion regions adjacent to the pair of spacers. The insulating cap layer forms an etch stop structure that is self aligned to the gate and prevents the contact etch from exposing the gate electrode, thereby preventing a short between the gate and contact. The insulator-cap layer enables self-aligned contacts, allowing initial patterning of wider contacts that are more robust to patterning limitations.

A semiconductor device includes a gate dielectric layer and a gate electrode formed on the gate dielectric layer. The gate electrode includes a first metal layer, a second metal layer, and a third metal layer. The first metal layer includes an oxygen-gettering composition. The second metal layer includes oxygen. The third metal layer includes an interface with a polysilicon layer.

Embodiments of the present disclosure provide wet process based methods for modifying threshold value (Vt) of high-k metal gate using self-assembled monolayer (SAM) on dedicated transistor. In one embodiment, the method includes forming a gate structure over a substrate, the gate structure comprising a gate dielectric layer, a barrier layer formed over the gate dielectric layer, and an oxide layer formed over the barrier layer, and forming a self-assembled monolayer on the oxide layer by exposing the oxide layer to an aqueous solution containing metal oxides in a metal dissolving acid.

A method of forming a high-K dielectric cap layer on a semiconductor structure formed on a substrate includes depositing the high-K dielectric cap layer on the semiconductor structure, depositing a sacrificial silicon cap layer on the high-K dielectric cap layer, performing a post cap anneal process to harden and densify the as-deposited high-K dielectric cap layer, and removing the sacrificial silicon cap layer.

A gate oxide forming process includes the following steps. A substrate including a first area and a second area is provided. A first oxide layer, a silicon containing cap layer and a second oxide layer on the substrate of the first area and the second area are sequentially and blanketly formed. The silicon containing cap layer and the second oxide layer in the first area are removed. An oxidation process is performed to oxidize the silicon containing cap layer and a gate oxide layer is formed in the second area.

A method for fabricating a semiconductor device includes forming a deposition-type interface layer over a substrate, converting the deposition-type interface layer into an oxidation-type interface layer, forming a high-k layer over the oxidation-type interface layer, forming a dipole interface on an interface between the high-k layer and the oxidation-type interface layer, forming a conductive layer over the high-k layer, and patterning the conductive layer, the high-k layer, the dipole interface, and the oxidation-type interface layer to form a gate stack over the substrate.

A gate oxide forming process includes the following steps. A substrate including a first area and a second area is provided. A first oxide layer, a silicon containing cap layer and a second oxide layer on the substrate of the first area and the second area are sequentially and blanketly formed. The silicon containing cap layer and the second oxide layer in the first area are removed. An oxidation process is performed to oxidize the silicon containing cap layer and a gate oxide layer is formed in the second area.