SOI substrate and method for production thereof
AssigneeNippon Steel Corporation
InventorsIsao Hamaguchi, Atsushi Ikari, Atsuki Matsumura, Keisuke Kawamura, Takayuki Yano, Yoichi Nagatake
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Abstract
A SOI substrate of high quality which allows LSI to be formed thereon in an improved yield and realizes excellent electric properties and a method for the production thereof are provided. The SOI substrate is obtained by forming an embedded oxide layer on a silicon single crystal substrate and forming a SOI layer for the formation of a device on the embedded oxide layer and is characterized by the SOI layer containing pit-like defects at a density of not more than 5 cm−2 or the embedded oxide layer containing pinhole defects at a density of less than one piece/cm2.
Claims4
A SOI substrate other than SIMOX allowing the presence of an embedded oxide film in a silicon single crystal substrate and comprising satisfying the following conditions:
- shape of pit-like defects observed from the surface of the SOI layer is a square or circle determined with an optical microscope, the density thereof being not more than 5 defects per square cm, each pit-like defect having an area in a range of 0.7-100 μm2;
- wherein a SOI structure is formed by using the following silicon single crystal substrate:
- a silicon single crystal substrate wherein a void and/or COP measuring not less than 0.1 μm as reduced to diameter is absent from at least the region from the surface to the depth for forming an embedded oxide layer.
A method for the production of a SOI substrate, comprising forming a SOI structure by using the following silicon single crystal substrate:
- a silicon single crystal substrate wherein a void and/or COP measuring not less than 0.1 μm as reduced to diameter is absent from at least the region from the surface to the depth for forming an embedded oxide layer.
A SIMOX substrate comprising containing pit-like defects observed from the surface of a SOI layer at a density of not more than 5 defects per square cm, the shape of the pit-like defects being a square or a circle determined with an optical microscope, each pit-like defect having an area in the range of 0.7-100 μm2,
- wherein a SOI structure is formed by using a silicon single crystal substrate wherein a void and/or COP measuring not less than 0.1 μm as reduced to a diameter is absent from at least the region from the surface to the depth for forming an embedded oxide layer.
A method for the production of a SOI substrate, comprising forming a SOI structure by using a silicon single crystal substrate wherein the region to be involved in the formation of a SOI structure has a density of defects of not more than 1×105 defects per cubic cm, the region ranging from a surface of the silicon crystal to a depth of 0.515 μm.
Dependencies are inferred from the claim text.