Semiconductor structure and fabrication method thereof
AssigneesSemiconductor Manufacturing International (Shanghai) Corporation, Semiconductor Manufacturing International (Beijing) Corporation
InventorMeng Zhao
Life of this patent
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Abstract
A semiconductor structure and a method for forming the semiconductor structure are provided. The semiconductor structure includes a substrate and a dummy gate structure on the substrate. The substrate contains source-drain openings on both sides of the dummy gate structure. The semiconductor structure also includes a first stress layer formed on a sidewall of a source-drain opening of the source-drain openings. Further, the semiconductor structure includes a second stress layer formed at a bottom of the source-drain opening and on the first stress layer. The second stress layer fully fills the source-drain opening, and stress of the first stress layer is less than stress of the second stress layer.
Claims17
A semiconductor structure, comprising:
- a substrate and a dummy gate structure on the substrate, wherein the substrate contains source-drain openings on both sides of the dummy gate structure;
- a first stress layer, formed on a sidewall of a source-drain opening of the source-drain openings;
- and
- a second stress layer, formed at a bottom of the source-drain opening and on the first stress layer, wherein the second stress layer fully fills the source-drain opening, and stress of the first stress layer is less than stress of the second stress layer;
- wherein:
- in response to a to-be-formed semiconductor structure being a P-type device, both the first stress layer and the second stress layer are made of silicon germanium, and a concentration of germanium in the first stress layer is a first concentration, and a concentration of germanium in the second stress layer is a second concentration, the first concentration being smaller than the second concentration;
- and
- in response to the to-be-formed semiconductor structure being an N-type device, both the first stress layer and the second stress layer are made of silicon phosphide, and a concentration of phosphorus in the first stress layer is a first concentration, and a concentration of phosphorus in the second stress layer is a second concentration, the first concentration being smaller than the second concentration.
A method for forming a semiconductor structure, comprising:
- providing a substrate and forming a dummy gate structure on the substrate;
- forming source-drain openings in the substrate on both sides of the dummy gate structure;
- forming a first stress layer on a sidewall of a source-drain opening of the source-drain openings;
- and
- forming a second stress layer at a bottom of the source-drain opening and on the first stress layer, wherein the second stress layer fully fills the source-drain opening, and stress of the first stress layer is less than stress of the second stress layer;
- wherein:
- in response to a to-be-formed semiconductor structure being a P-type device, both the first stress layer and the second stress layer are made of silicon germanium, and a concentration of germanium in the first stress layer is a first concentration, and a concentration of germanium in the second stress layer is a second concentration, the first concentration being smaller than the second concentration;
- and
- in response to the to-be-formed semiconductor structure being an N-type device, both the first stress layer and the second stress layer are made of silicon phosphide, and a concentration of phosphorus in the first stress layer is a first concentration, and a concentration of phosphorus in the second stress layer is a second concentration, the first concentration being smaller than the second concentration.
Dependencies are inferred from the claim text.