Semiconductor devices and methods of manufacture thereof are disclosed. In some embodiments, a method of manufacturing a semiconductor device includes providing a substrate, the substrate includes a first fin, a second fin, and an isolation region disposed between the first fin and the second fin. The second fin includes a different material than a material of the substrate. The method includes forming an oxide over the first fin, the second fin, and a top surface of the isolation region at a temperature of about 400 degrees C. or less, and post-treating the oxide at a temperature of about 600 degrees C. or less.

The invention relates to a method of providing a structure by depositing a layer on a substrate in a reactor. The method comprising: introducing a silicon halide precursor in the reactor; introducing a reactant gas comprising oxygen in the reactor; and, providing an energy source to create a plasma from the reactant gas so that the oxygen reacts with the first precursor in a layer comprising silicon dioxide.

A plasma processing method includes a substrate processing step of performing predetermined processing on a target substrate loaded into a chamber by using plasma of a hydrogen-containing gas and unloading the processed substrate from the chamber; and an in-chamber processing step of processing surfaces of components in the chamber by plasma of an oxygen-containing gas after the substrate processing step is performed at least once. The substrate processing step is performed again at least once after the in-chamber processing step.

Isotropic silicon and silicon-germanium etching with tunable selectivity is described. The method includes receiving a substrate having a layer of silicon and a layer of silicon-germanium with sidewall surfaces of silicon and silicon-germanium being uncovered, positioning the substrate in a processing chamber configured for etching substrates, and modifying uncovered surfaces of silicon and silicon-germanium by exposing the uncovered surfaces of silicon and silicon-germanium to radical species. The method further includes executing a gaseous chemical oxide removal process that includes flowing a mixture of a nitrogen-containing gas and a fluorine-containing gas at a first substrate temperature to form a fluorine byproduct followed by executing a sublimation process to remove the fluorine byproduct at a second substrate temperature that is higher than the first substrate temperature, and controlling the second substrate temperature to tune the sublimation rate and etch selectivity of a silicon oxide material relative to a silicon-germanium oxide material.

Methods and apparatuses suitable for depositing low hydrogen content, hermetic, thin encapsulation layers at temperatures less than about 300° C. are provided herein. Methods involve pulsing plasma while exposing a substrate to deposition reactants, and post-treating deposited encapsulation films to densify and reduce hydrogen content. Post-treatment methods include periodic exposure to inert plasma without reactants and exposure to ultraviolet radiation at a substrate temperature less than about 300° C.

Methods for forming a spacer comprising depositing a film on the top, bottom and sidewalls of a feature and treating the film to change a property of the film on the top and bottom of the feature. Selectively dry etching the film from the top and bottom of the feature relative to the film on the sidewalls of the feature using a high intensity plasma.

Methods for forming a spacer comprising depositing a film on the top, bottom and sidewalls of a feature and treating the film to change a property of the film on the top and bottom of the feature so that the film can be selectively etched from the top and bottom of the feature relative to the film on the sidewalls of the feature.

A semiconductor process including the following steps is provided. An epitaxial layer is formed on a substrate. An oxide layer is formed on the epitaxial layer, wherein the oxide layer includes a chemical oxide layer, a high-temperature oxide (HTO) layer or a surface modification oxide layer. An ion implant process is performed to the epitaxial layer to form a doped region in the epitaxial layer. The oxide layer is removed by using a diluted hydrofluoric acid (DHF) solution after performing the ion implant process, wherein a volume ratio of water to a hydrofluoric acid (HF) in the DHF solution is 200:1 to 1000:1.

A method of forming a gate dielectric layer for a MOS transistor includes the following steps. A gate dielectric layer is formed on a substrate. A nitridation process is performed on the gate dielectric layer. A multi-step post nitridation annealing process including two oxygen-containing annealing steps with different respective annealing temperatures is performed on the gate dielectric layer.

A semiconductor device structure is provided. The semiconductor device includes a first nanowire structure over a second nanowire structure, a gate stack wrapping around the first nanowire structure and the second nanowire structure, a source/drain feature adjoining the first nanowire structure and the second nanowire structure, a gate spacer layer over the first nanowire structure and between the gate stack and the source/drain feature, and an inner spacer layer between the first nanowire structure and the second nanowire structure and between the gate stack and the source/drain feature. The gate spacer layer has a first carbon concentration, the inner spacer has a second carbon concentration, and the second carbon concentration is lower than the first carbon concentration.