Abstract: A method for determining a defect region of a silicon wafer which is sliced off from a silicon single crystal manufactured by a CZ method, the method including: (1) mirror-surface processing the silicon wafer in such a manner that a haze level of a surface thereof in haze measurement performed by a particle counter which uses a laser having a wavelength of 266 nm becomes 0.06 ppm or less; (2) measuring the number of defects and/or a defect density distribution on the mirror-surface-processed surface of the silicon wafer by using a particle counter capable of measuring defects having a size of 15 nm or less; and (3) determining the defect region of the silicon wafer from the measured number of the defects and/or defect density distribution.

Abstract: A method for determining a defect region of a silicon wafer which is sliced off from a silicon single crystal manufactured by a CZ method, the method including: (1) mirror-surface processing the silicon wafer in such a manner that a haze level of a surface thereof in haze measurement performed by a particle counter which uses a laser having a wavelength of 266 nm becomes 0.06 ppm or less; (2) measuring the number of defects and/or a defect density distribution on the mirror-surface-processed surface of the silicon wafer by using a particle counter capable of measuring defects having a size of 15 nm or less; and (3) determining the defect region of the silicon wafer from the measured number of the defects and/or defect density distribution.

Abstract: The present invention provides a method for manufacturing a silicon single crystal wafer, in which a silicon single crystal wafer that is fabricated based on a Czochralski method and has an entire plane in a radial direction formed of an N region is subjected to a rapid thermal annealing in an oxidizing atmosphere, an oxide film formed in the rapid thermal annealing in the oxidizing atmosphere is removed, and then a rapid thermal annealing is carried out in a nitriding atmosphere, an Ar atmosphere, or a mixed atmosphere of these atmospheres. As a result, there can be provided the manufacturing method that can inexpensively manufacture a silicon single crystal wafer both in which a DZ layer is formed in a wafer surface layer to provide excellent device characteristics and in which an oxide precipitate functioning as a gettering site can be sufficiently formed in a bulk region.

Abstract: An annealed wafer obtained by performing rapid thermal annealing on a silicon single crystal wafer sliced from a silicon single crystal ingot in which an entire plane is an OSF region, an N region outside an OSF region, or a mixed region thereof, the silicon single crystal ingot being grown by the Czochralski method, in which RIE defects do not exist in a region having at least a depth of 1 ?m from a surface, a good chip yield of a TDDB characteristic is 80% or more, and a depth of a region where an oxygen concentration is decreased due to outward diffusion is within 3 ?m from the surface, and a method for producing an annealed wafer.

Abstract: The present invention provides a method for manufacturing a silicon single crystal wafer, in which a silicon single crystal wafer that is fabricated based on a Czochralski method and has an entire plane in a radial direction formed of an N region is subjected to a rapid thermal annealing in an oxidizing atmosphere, an oxide film formed in the rapid thermal annealing in the oxidizing atmosphere is removed, and then a rapid thermal annealing is carried out in a nitriding atmosphere, an Ar atmosphere, or a mixed atmosphere of these atmospheres. As a result, there can be provided the manufacturing method that can inexpensively manufacture a silicon single crystal wafer both in which a DZ layer is formed in a wafer surface layer to provide excellent device characteristics and in which an oxide precipitate functioning as a gettering site can be sufficiently formed in a bulk region.

Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less O, 0.005% or less S, by weight, having 10 ?m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C./sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.

Abstract: A method for manufacturing a steel sheet comprising rough-rolling a steel consisting essentially of 0.04 to 0.12 weight % C, 0.25 to 2 weight % Si, 0.5 to 2.5 weight % Mn, 0.1 weight % or less Al, and a balance of substantially Fe and inevitable impurities to form a sheet bar; finish-rolling the sheet bar at a rolling end temperature of the Ar3 transformation point or more; primary-cooling the finish-rolled steel sheet within 1 second after completing the finish-rolling at a cooling speed of higher than 200° C./sec through a cooling range where-the difference between the start temperature of the cooling and the end temperature of the cooling is 100° C. to below 250° C.; slowly cooling the primary-cooled steel at a cooling speed of 10° C./sec or less, for 2 seconds to less than 20 seconds, at a temperature of 580° C. to 720° C.; and coiling the slowly cooled steel sheet at a temperature of 400° C. to below 540° C.

Abstract: A method for manufacturing a steel sheet comprising continuously casting a steel containing 0.04 to 0.2 wt. % C, 0.25 to 2 wt. % Si, 0.5 to 2.5 wt. % Mn, and 0.1 wt. % or less Al to form a slab; hot-rolling by rough-rolling the slab to form a sheet bar and finish-rolling the sheet bar with a reduction in thickness at the final stand of less than 30%, the finish-rolling being completed at a temperature from the Ar3 transformation point to the Ar3 transformation point +60° C.; primary-cooling the hot-rolled steel sheet, the primary cooling being started within 1 second after the completion of hot-rolling and conducting the cooling at a cooling speed of higher than 200° C./sec down to a temperature of Ar3 −30° C. to the Ar1 transformation point; slow cooling or air-cooling the primary-cooled steel sheet at a temperature of the Ar3 transformation point to the Ar1 transformation point at 10° C.

Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less O, 0.005% or less S, by weight, having 10 &mgr;m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C./sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.

Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less 0, 0.005% or less S, by weight, having 10 &mgr;m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C./sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.

Abstract: The method for manufacturing steel sheet comprises the steps of: rough-rolling to form a sheet bar; finish-rolling the sheet bar to form a steel strip; applying primary cooling and secondary cooling to the finish-rolled steel strip; and coiling the secondary-cooled steel strip. The primary cooling is conducted at cooling speeds of 120° C./sec or more down to the temperatures of from 500 to 800° C. The secondary cooling is conducted at cooling speeds of less than 60° C./sec.

Abstract: A method for manufacturing a steel sheet comprising continuously casting a steel containing 0.04 to 0.2 wt. % C, 0.25 to 2 wt. % Si, 0.5 to 2.5 wt. % Mn, and 0.1 wt. % or less Al to form a slab; hot-rolling by rough-rolling the slab to form a sheet bar and finish-rolling the sheet bar with a reduction in thickness at the final stand of less than 30%, the finish-rolling being completed at a temperature from the Ar3 transformation point to the Ar3 transformation point +60° C.; primary-cooling the hot-rolled steel sheet, the primary cooling being started within 1 second after the completion of hot-rolling and conducting the cooling at a cooling speed of higher than 200° C./sec down to a temperature of Ar3 −30° C. to the Ar1 transformation point; slow cooling or air-cooling the primary-cooled steel sheet at a temperature of the Ar3 transformation point to the Ar1 transformation point at 10° C.

Abstract: A high tensile strength hot-rolled steel sheet comprises 0.04 to 0.09% C, 0.1% or less Si, 0.5 to 1.5% Mn, 0.02% or less P, 0.01% or less S, 0.1% or less Al, 0.001 to 0.008% N, and 0.01 to 0.15% Ti, by mass %, the content of ingredient there each satisfying the equation (1), and the ferritic grain size &agr; (&mgr;m) satisfying the equation (2): [C]+7×[Si]+0.1×[Mn]+[P]+14×[S]+1.75×[Al] +23×[N]+[Ti]+18×[O]+7×[Cu]+18×[Sn]+7×[Mo]+ 1.7×[Cr]+70×[B]+7×[Ca]+14×[Zr]+14×[V]+7×[Nb] ≦2  (1) 3≦&agr;≦60×[Ti]+8  (2) where, [X] denotes the content (mass %) of element X.

Abstract: The method for manufacturing steel sheet comprises the steps of: forming a sheet bar; forming a steel strip; primary-cooling; air-cooling; secondary-cooling; and coiling. The sheet bar is finish-rolled at finish temperatures of (Ar3 transformation point −20° C.) or more. The primary cooling cools the finish-rolled steel strip at cooling speeds of more than 120° C./sec down to the temperatures ranging from 500 to 800° C.

Abstract: A high tensile strength hot-rolled steel sheet comprises 0.04 to 0.09% C, 0.1% or less Si, 0.5 to 1.5% Mn, 0.02% or less P, 0.01% or less S, 0.1% or less Al, 0.001 to 0.008% N, and 0.01 to 0.

Abstract: The method for manufacturing steel sheet comprises the steps of: forming a sheet bar; forming a steel strip; primary-cooling; air-cooling; secondary-cooling; and coiling. The sheet bar is finish-rolled at finish temperatures of (Ar3 transformation point−20° C.) or more. The primary cooling cools the finish-rolled steel strip at cooling speeds of more than 120° C./sec down to the temperatures ranging from 500 to 800° C.

Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less 0, 0.005% or less S, by weight, having 10 &mgr;m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C. /sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.

Abstract: The method for manufacturing steel sheet comprises the steps of: rough-rolling to form a sheet bar; finish-rolling the sheet bar to form a steel strip; applying primary cooling and secondary cooling to the finish-rolled steel strip; and coiling the secondary-cooled steel strip. The primary cooling is conducted at cooling speeds of 120° C./sec or more down to the temperatures of from 500 to 800° C. The secondary cooling is conducted at cooling speeds of less than 60° C./sec.