Epitaxial silicon wafer, method for producing same, and method for producing semiconductor device
AssigneeSumco Corporation
InventorsRyo Hirose, Takeshi Kadono
Life of this patent
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Abstract
A method of producing an epitaxial silicon wafer includes irradiating a surface of a silicon wafer with a beam of cluster ions containing SiHx ions (at least one of the integers 1 to 3 is selected as x of the SiHx ions) and C2Hy ions (at least one of the integers 2 to 5 is selected as y of the C2Hy ions) to form a modified layer that is located in a surface layer portion of the silicon wafer and that contains as a solid solution of the constituent elements of the cluster ion beam, and further includes forming a silicon epitaxial layer on the modified layer of the silicon wafer. The dose of the SiHx ions is 1.5×1014 ions/cm2 or more.
Claims8
A method of producing an epitaxial silicon wafer, the method comprising:
- a step of irradiating a surface of a silicon wafer with a cluster ion beam including SiHx ions and C2Hy ions to form a modified layer that is located in a surface layer portion of the silicon wafer and that contains a solid solution of constituent elements of the cluster ion beam, where at least one of the integers 1 to 3 is selected as x of the SiHx ions, and at least one of the integers 2 to 5 is selected as y of the C2Hy ions;
- and
- a step of forming a silicon epitaxial layer on the modified layer of the silicon wafer,
- wherein a dose of the SiHx ions is 1.5×1014 ions/cm2 or more.
An epitaxial silicon wafer comprising:
- a silicon wafer;
- a modified layer that is located in a surface layer portion of the silicon wafer and that contains a solid solution of at least one of carbon and hydrogen;
- and
- a silicon epitaxial layer formed on the modified layer,
- wherein in a defect analysis using a cross-sectional TEM image of the modified layer, a defect region in which EOR defects having a maximum width of 50 nm to 250 nm are present at a density of 5.0×107/cm2 or more is observed,
- an amount of carbon distributed in the silicon epitaxial layer and the modified layer is 2.0×1014 atoms/cm2 or less, and
- in a hydrogen concentration profile in a depth direction of the modified layer, found by SIMS, a peak concentration is 1.0×1016 atoms/cm3 or more.
Dependencies are inferred from the claim text.