Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.

A method of producing a monocrystalline silicon uses a monocrystal pull-up apparatus including a crucible, a crucible driver, a pull-up portion, a heat shield having a circular hollow cylindrical lower end portion, and a chamber. The heat shield satisfies a formula (1) below in growing the monocrystalline silicon,
R≤1.27×C  (1) where C represents a radius (mm) of a straight body of the monocrystalline silicon, and R represents an inner radius (mm) at the lower end portion of the heat shield.

A method for growing a single crystal silicon ingot by the Czochralski method having reduced deviation in diameter is disclosed.

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 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.

Provided is a large diameter InP single crystal substrate having a diameter of 75 mm or more, which can achieve a high electrical activation rate of Zn over a main surface of the substrate even in a highly doped region having a Zn concentration of 5×10.sup.18 cm.sup.−3 or more; and a method for producing the same. An InP single crystal ingot is cooled such that a temperature difference of 200° C. is decreased for 2 to 7.5 minutes, while rotating the InP single crystal ingot at a rotation speed of 10 rpm or less, and the cooled InP single crystal ingot is cut into a thin plate, thereby allowing production of the InP single crystal substrate having an electrical activation rate of Zn of more than 85% over the main surface of the substrate even in a highly doped region having a Zn concentration of 5×10.sup.18 cm.sup.−3 or more.

A production method of a monocrystalline silicon includes: forming a shoulder of the monocrystalline silicon; and forming a straight body of the monocrystalline silicon. In forming the shoulder, the shoulder is formed such that a part of growth striations, which extend radially across the shoulder, has an outer end interrupted by another part of the growth striations not to reach a peripheral portion of the shoulder and that no remelt growth area with a height of 200 μm or more in a growth direction is generated.

The present invention relates to an ingot growth control device capable of quickly and accurately controlling a diameter of an ingot during an ingot growing process and improving quality of the ingot, and a control method thereof. In the ingot growth control device and a control method thereof according to the present invention, when an input unit provides diameter data obtained by filtering a diameter measurement value of an ingot, a diameter controller reflects the diameter data to control a pulling speed of the ingot, while a temperature controller reflects the diameter data to control power of a heater.

A method of controlling a convection pattern of a silicon melt includes: acquiring a temperature at a first measurement point not overlapping a rotation center of a quartz crucible on a surface of the silicon melt, the quartz crucible rotating in a magnetic-field-free state; determining that the temperature at the first measurement point periodically changes; and fixing a direction of a convection flow to a single direction in a plane orthogonal with an application direction of a horizontal magnetic field in the silicon melt by starting a drive of a magnetic-field applying portion to apply the horizontal magnetic field to the silicon melt when a temperature change at the first measurement point reaches a predetermined state, and subsequently raising the intensity to 0.2 tesla or more.

Semiconductor wafers useful for NAND circuitry and having a front side, a rear side, a middle and a periphery, have an Nv region which extends from the middle to the periphery; a denuded zone which extends from the front side to a depth of not less than 20 m into the interior of the semiconductor wafer, where the density of vacancies in the denuded zone, determined by means of platinum diffusion and DLTS is not more than 110.sup.13 vacancies/cm.sup.3; a concentration of oxygen of not less than 4.510.sup.17 atoms/cm.sup.3 and not more than 5.510.sup.17 atoms/cm.sup.3; a region in the interior of the semiconductor wafer which adjoins the denuded zone and has nuclei which can be developed by means of a heat treatment into BMDs having a peak density of not less than 6.010.sup.9/cm.sup.3, where the heat treatment comprises heating the semiconductor wafer to a temperature of 800 C. over a period of four hours and to a temperature of 1000 C. over a period of 16 hours. The wafers are produced by a unique RTA treatment of Nv wafers.