Abstract: The epitaxial layer defects generated from voids of a silicon substrate wafer containing added hydrogen are suppressed by a method for producing an epitaxial wafer by: growing a silicon crystal by the Czochralski method comprising adding hydrogen and nitrogen to a silicon melt and growing from the silicon melt a silicon crystal having a nitrogen concentration of from 3×1013 cm?3 to 3×1014 cm?3, preparing a silicon substrate by machining the silicon crystal, and forming an epitaxial layer at the surface of the silicon substrate.

Abstract: This disclosure is aimed at providing a method for producing an epitaxial wafer allowing uniform occurrence of oxygen precipitate in a substrate plane in the radial direction in a base plate and excelling in the crystal quality of an epi-layer. A method for the production of an epitaxial wafer, characterized by using as a substrate a base plate of nitrogen- and carbon-added silicon single crystal having a nitrogen concentration of 5×1014 to 5×1015 atoms/cm3 and a carbon concentration of 1×1016 to 1×1018 atoms/cm3, having a crystal growth condition during the production of silicon single crystal in a range in which the whole surface of substrate becomes an OSF region, and being pulled at a cooling speed of not less than 4° C./minute between 1100 and 1000° C. during the growth of crystal, and depositing the silicon single crystal layer on the surface of the substrate by the epitaxial method.

Abstract: Silicon wafers having excellent voltage resistance characteristics of an oxide film and high C-mode characteristics are derived from single crystal silicon ingots doped with nitrogen and hydrogen, characterized in that a plurality of voids constituting a bubble-like void aggregates are present ?50% relative to total voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 is ?20% of the total area of wafer; a V2 region having a void density of 5×102 to 2×104/cm3 occupies ?80% of the total area of the wafer; and bulk microdefect density is ?5×108/cm3.

Abstract: A silicon wafer in which both occurrences of slip dislocation and warpage are suppressed in device manufacturing processes is a silicon wafer having BMDs having an octahedral shape, wherein BMDs located at a position below the silicon wafer surface to a depth of 20 ?m and having a diagonal length of 200 nm or more are present at a concentration of ?2×109/cm3, and BMDs located at a position below a depth ?50 ?m have a diagonal length of ?10 nm to ?50 nm and a concentration of ?1×1012/cm3.

Abstract: An annealed wafer having enhanced gettering effects for Cu is produced by heating a silicon substrate containing a nitrogen concentration of 5×1014 to 1×1016/cm3, a carbon concentration of 1×1015 to 5×1016/cm3, and an oxygen concentration of 6×1017 to 11×1017/cm3 at a temperature of 650 to 800° C. for a time ?4 hours, and subjecting the heated substrate to argon annealing at a temperature of 1100 to 1250° C., wherein internal stacking fault density after annealing is ?5×108/cm3.

Abstract: Silicon wafers wherein slip dislocations and warpages during device production are suppressed, contain BMDs with an octahedral shape, and of BMDs at a depth greater than 50 ?m from the surface of the wafer, the density of BMDs with diagonal size of 10 nm to 50 nm is ?1×1012/cm3, and the density of BSFs is ?1×108/cm3. The present silicon wafers preferably have an interstitial oxygen concentration of 4×1017 atoms/cm3 to 6×1017 atoms/cm3, and a density of BMDs with diagonal size of ?200 nm of not more than 1×107/cm3.

Abstract: The Czochralski method is used for producing p?-doped and epitaxially coated semiconductor wafers from silicon, wherein a silicon single crystal is pulled, and during the pulling is doped with boron, hydrogen and nitrogen, and the single crystal thus obtained is processed to form p?-doped semiconductor wafers which are epitaxially coated.

Abstract: Silicon wafers and a process for their manufacture wherein both slip dislocation and occurrence of warpage are suppressed include heat treatment to provide wafers having plate-shaped BMDs, a density of BMDs whose diagonal lengths are in a range of 10 nm to 120 nm, of BMDs present in the bulk of the wafer at a distance of 50 ?m or more is 1×1011/cm3 or more, and the density of BMDs whose diagonal lengths are 750 nm or more in the wafer bulk is 1×107/cm3 or less, and the interstitial oxygen concentration is 5×1017 atoms/cm3 or less. The process involves low and high temperature heat treating at under defined temperature ramping rates.

Abstract: Silicon wafers having a density of BMDs with sizes between 20 to 40 nm at positions ?20 ?m below the wafer surface in the range of 5×1011/cm3, and a density of BMDs with sizes of ?300 nm?1×107/cm3, exhibit reduced slip dislocation and warpage. The wafers are sliced from a crystal grown under specific conditions and then subjected to both low temperature heat-treatment and high temperature anneal.

Abstract: The Czochralski method is used for producing p?-doped and epitaxially coated semiconductor wafers from silicon, wherein a silicon single crystal is pulled, and during the pulling is doped with boron, hydrogen and nitrogen, and the single crystal thus obtained is processed to form p?-doped semiconductor wafers which are epitaxially coated.

Abstract: This disclosure is aimed at providing a method for producing an epitaxial wafer allowing uniform occurrence of oxygen precipitate in a substrate plane in the radial direction in a base plate and excelling in the crystal quality of an epi-layer. A method for the production of an epitaxial wafer, characterized by using as a substrate a base plate of nitrogen- and carbon-added silicon single crystal having a nitrogen concentration of 5×1014 to 5×1015 atoms/cm3 and a carbon concentration of 1×1016 to 1×1018 atoms/cm3, having a crystal growth condition during the production of silicon single crystal in a range in which the whole surface of substrate becomes an OSF region, and being pulled at a cooling speed of not less than 4° C./minute between 1100 and 1000° C. during the growth of crystal, and depositing the silicon single crystal layer on the surface of the substrate by the epitaxial method.

Abstract: An annealed wafer in which oxygen precipitation is uniform in the substrate plane and a manufacturing method thereof are provided. A nitrogen-doped silicon single crystal substrate pulled at the cooling rate of 4° C./minute or more during crystal growth between 1100 and 1000° C. wherein the nitrogen concentration is 1×1014 to 5×1015 atoms/cm3 and V/G satisfies predetermined conditions serves as a substrate, and the substrate is subjected to heat treatment in a non-oxidative atmosphere.

Abstract: A silicon semiconductor substrate is obtained by deriving a silicon semiconductor substrate from a silicon single crystal grown by the Czochralski method from a molten silicon containing not less than 1×1016 atoms/cm3 and not more than 1.5×1019 atoms/cm3 of nitrogen and heat-treating the silicon semiconductor substrate at a temperature of not less than 1000° C. and not more than 1300° C. for not less than one hour and is characterized by the fact that the density of crystal defects measuring not less than 0.1 &mgr;m as reduced to diameter is not more than 104 pieces/cm3 at least in the region reaching a depth of 1 &mgr;m from the surface of the substrate and the nitrogen content at the center of thickness of the silicon semiconductor substrate is not less than 1×1013 atoms/cm3 and not more than 1×1016 atoms/cm3.