A method for fabricating 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, and removing part of the gate material layer and part of the gate dielectric layer to form a gate electrode, in which a top surface of the gate dielectric layer adjacent to two sides of the gate electrode is lower than a top surface of the gate dielectric layer between the gate electrode and the substrate. Next, a first mask layer is formed on the gate dielectric layer and the gate electrode, part of the first mask layer and part of the gate dielectric layer are removed to form a first spacer, a second mask layer is formed on the substrate and the gate electrode, and part of the second mask layer is removed to forma second spacer.

A method for preparing a single crystal silicon ingot and a wafer sliced therefrom are provided. The ingots and wafers comprise nitrogen at a concentration of at least about 1×10.sup.14 atoms/cm.sup.3 and/or germanium at a concentration of at least about 1×10.sup.19 atoms/cm.sup.3, interstitial oxygen at a concentration of less than about 6 ppma, and a resistivity of at least about 1000 ohm cm.

A method for improving a bias temperature instability of a SiO.sub.2 layer comprises exposing the SiO.sub.2 layer to atomic hydrogen.

A semiconductor device includes a substrate and a fin feature over the substrate. The fin feature includes a first portion of a first semiconductor material and a second portion of a second semiconductor material disposed over the first portion. The second semiconductor material is different from the first semiconductor material. The semiconductor device further includes a semiconductor oxide feature disposed on sidewalls of the first portion and a gate stack disposed on the fin feature. The gate stack includes an interfacial layer over a top surface and sidewalls of the second portion and a gate dielectric layer over the interfacial layer and sidewalls of the semiconductor oxide feature. A portion of the gate dielectric layer is below the interfacial layer.

A method for fabricating a semiconductor device includes forming a fin extending along a first direction on a semiconductor substrate and forming a sacrificial gate electrode structure extending along a second direction substantially perpendicular to the first direction over the fin. The sacrificial gate electrode structure comprises a sacrificial gate dielectric layer and a sacrificial gate electrode layer disposed over the sacrificial gate dielectric layer. Opposing gate sidewall spacers are formed extending along the second direction, on opposing sides of the sacrificial gate electrode layer. The sacrificial gate electrode layer is removed to form a gate space. Fluorine is implanted into the gate sidewall spacers after removing the gate electrode layer by performing a first fluorine implantation. The sacrificial gate dielectric layer is removed and a high-k gate dielectric layer is formed in the gate space. Fluorine is implanted into the gate sidewall spacers and the fin after forming the high-k gate dielectric layer by performing a second fluorine implantation.

A semiconductor device includes at least one active pattern on a substrate, at least one gate electrode intersecting the at least one active pattern, source/drain regions on the at least one active pattern, the source/drain regions being on opposite sides of the at least one gate electrode, and a barrier layer between at least one of the source/drain regions and the at least one active pattern, the barrier layer being at least on bottoms of the source/drain regions and including oxygen.

A pressure sensor die especially suitable for high-temperature, high-pressure operating environment and delivering accurate and reliable pressure measurement at low cost. A single crystalline silicon includes a cap, a substrate and a base connected together. A recess formed on the cap creates an upper sealed cavity with the substrate. A silicon oxide layer is formed between the substrate and the cap. A recess formed on the base creates a lower sealed cavity with the substrate. The upper sealed cavity and the lower sealed cavity overlap in their projections. The substrate includes at least two sets of piezoresistive sensing elements located within the overlapping projections, perpendicular to each other, and oriented in different crystallographic directions.

A semiconductor device includes at least one active pattern on a substrate, at least one gate electrode intersecting the at least one active pattern, source/drain regions on the at least one active pattern, the source/drain regions being on opposite sides of the at least one gate electrode, and a barrier layer between at least one of the source/drain regions and the at least one active pattern, the barrier layer being at least on bottoms of the source/drain regions and including oxygen.

A method of forming a nanostructure field-effect transistor (nano-FET) device includes: forming a fin structure that includes a fin and alternating layers of a first semiconductor material and a second semiconductor material overlying the fin; forming a dummy gate structure over the fin structure; forming source/drain regions over the fin structure on opposing sides of the dummy gate structure; removing the dummy gate structure to expose the first and second semiconductor materials under the dummy gate structure; selectively removing the exposed first semiconductor material, where after the selectively removing, the exposed second semiconductor material remains to form nanostructures, where different surfaces of the nanostructures have different atomic densities of the second semiconductor material; forming a gate dielectric layer around the nanostructures, thicknesses of the gate dielectric layer on the different surfaces of the nanostructures being formed substantially the same; and forming a gate electrode around the gate dielectric layer.

A semiconductor device includes a substrate and a fin feature over the substrate. The fin feature includes a first portion of a first semiconductor material and a second portion of a second semiconductor material disposed over the first portion. The second semiconductor material is different from the first semiconductor material. The semiconductor device further includes a semiconductor oxide feature disposed on sidewalls of the first portion and a gate stack disposed on the fin feature. The gate stack includes an interfacial layer over a top surface and sidewalls of the second portion and a gate dielectric layer over the interfacial layer and sidewalls of the semiconductor oxide feature. A portion of the gate dielectric layer is below the interfacial layer.