A silicon wafer having a layer of oxygen precipitates and method of manufacturing thereof wherein the wafer exhibiting robustness characterized as having a ratio of a first average density from a first treatment that to a second average density from a second treatment is between 0.74 to 1.02, wherein the first treatment includes heating the wafer or a portion of the wafer at about 1150° C. for about 2 minutes and then between about 950 to 1000° C. for about 16 hours, and the second treatment includes heating the wafer or a portion of the wafer at about 780° C. for about 3 hours and then between about 950 to 1000° C. for about 16 hours. The wafer exhibits heretofore unattainable uniformity wherein a ratio of an oxygen precipitate density determined from any one cubic centimeter in the BMD layer of the wafer to another oxygen precipitate density from any other one cubic centimeter in the BMD layer of the wafer is in a range of 0.77 to 1.30.

A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. The melt depth and thermal conditions are constant during growth because the silicon melt is continuously replenished as it is consumed, and the crucible location is fixed. The critical v/G is determined by the hot zone configuration, and the continuous replenishment of silicon to the melt during growth enables growth of the ingot at a constant pull rate consistent with the critical v/G during growth of a substantial portion of the main body of the ingot. The continuous replenishment of silicon is accompanied by periodic or continuous nitrogen addition to the melt to result in a nitrogen doped ingot.

A method for making a semiconductor device may include forming first and second superlattices adjacent a semiconductor layer. Each of the first and second superlattices may include stacked groups of layers, with each group of layers including stacked base semiconductor monolayers defining a base semiconductor portion and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions. The second superlattice may have a greater thermal stability with respect to non-semiconductor atoms therein than the first superlattice. The method may further include heating the first and second superlattices to cause non-semiconductor atoms from the first superlattice to migrate toward the at least one non-semiconductor monolayer of the second superlattice.

A processing temperature T.sub.S by a rapid thermal processing furnace is 1250° C. or more and 1350° C. or less, and a cooling rate R.sub.d from the processing temperature is in a range of 20° C./s or more and 150° C./s or less, and thermal processing is performed by adjusting the processing temperature T.sub.S and the cooling rate R.sub.d within a range between the upper limit P=0.00207T.sub.S.Math.R.sub.d−2.52R.sub.d+13.3 (Formula (A)) and the lower limit P=0.000548T.sub.S.Math.R.sub.d−0.605R.sub.d−0.511 (Formula (B)) of an oxygen partial pressure P in a thermal processing atmosphere.

It is an object to provide technology enabling reduction in variation of an oxygen concentration among silicon wafers. A semiconductor device manufacturing method includes: a first step of introducing oxygen to increase an oxygen concentration of a silicon wafer when the oxygen concentration of the silicon wafer is lower than a predetermined threshold, and deriving oxygen to decrease the oxygen concentration of the silicon wafer when the oxygen concentration of the silicon wafer is higher than the threshold; a second step of forming a first surface structure; a third step of grinding the silicon wafer from a second surface; and a fourth step of forming a second surface structure.

A carrier substrate comprises monocrystalline silicon, and has a front face and a back face. The carrier substrate comprises: a surface region extending from the front face to a depth of between 800 nm and 2 microns, having less than 10 crystal-originated particles (COPs) (as detected by inspecting the surface using dark-field reflection microscopy); an upper region extending from the front face to a depth of between a few microns and 40 microns and having an interstitial oxygen (Oi) content less than or equal to 7.5E17 Oi/cm.sup.3 and a resistivity higher than 500 ohm.Math.cm, and a lower region extending between the upper region and the back face and having a micro-defect (BMD) concentration greater than or equal to 1E8/cm.sup.3.

A method is used to manufacture such a carrier substrate.

A silicon wafer is provided in which a dopant is phosphorus, resistivity is 1.2 mΩ.Math.cm or less, and carbon concentration is 3.5×10.sup.15 atoms/cm.sup.3 or more. The carbon concentration is decreased by 10% or more near a surface of the silicon wafer compared with a center-depth of the silicon wafer.

Epitaxially coated semiconductor wafers of monocrystalline silicon comprise a p.sup.+-doped substrate wafer and a p-doped epitaxial layer of monocrystalline silicon which covers an upper side face of the substrate wafer;

an oxygen concentration of the substrate wafer of not less than 5.3×10.sup.17 atoms/cm.sup.3 and not more than 6.0×10.sup.17 atoms/cm.sup.3;

a resistivity of the substrate wafer of not less than 5 mΩcm and not more than 10 mΩcm; and

the potential of the substrate wafer to form BMDs as a result of a heat treatment of the epitaxially coated semiconductor wafer, where a high density of BMDs has a maximum close to the surface of the substrate wafer.

Epitaxially coated semiconductor wafers of monocrystalline silicon comprise a p.sup.+-doped substrate wafer and a p-doped epitaxial layer of monocrystalline silicon which covers an upper side face of the substrate wafer; an oxygen concentration of the substrate wafer of not less than 5.3×10.sup.17 atoms/cm.sup.3 and not more than 6.0×10.sup.17 atoms/cm.sup.3; a resistivity of the substrate wafer of not less than 5 mΩcm and not more than 10 mΩcm; and
the potential of the substrate wafer to form BMDs as a result of a heat treatment of the epitaxially coated semiconductor wafer, where a high density of BMDs has a maximum close to the surface of the substrate wafer.

A semiconductor wafer made of single-crystal silicon has an oxygen concentration (new ASTM) of not less than 4.9×10.sup.17 atoms/cm.sup.3 and not more than 6.5×10.sup.7 atoms/cm.sup.3 and a nitrogen concentration (new ASTM) of not less than 8×10.sup.12 atoms/cm.sup.3 and not more than 5×10.sup.13 atoms/cm.sup.3, wherein a frontside of the semiconductor wafer is covered with an epitaxial layer made of silicon, wherein the semiconductor wafer comprises BMDs of octahedral shape whose mean size is 13 to 35 nm, and whose mean density is not less than 3×10.sup.8 cm.sup.−3 and not more than 4×10.sup.9 cm.sup.−3, as determined by IR tomography.