The present disclosure provides a method for automatically controlling material suction in a process of pulling-up of a monocrystal, including the steps of: obtaining a lifetime value and a resistivity of a pulled monocrystalline silicon rod; determining the lifetime value and a ratio of the lifetime value to the resistivity of the pulled monocrystalline silicon rod; if both the lifetime value and the ratio of the lifetime value to the resistivity are greater than set values, continuing to perform a re-feeding and pulling procedure; and if the lifetime value or/and the ratio of the lifetime value to the resistivity is less than or equal to the set values, performing a segment-taking and material suction procedure.

A method of controlling a convection pattern of a silicon melt includes applying a horizontal magnetic field having an intensity of 0.2 tesla or more to the silicon melt in a rotating quartz crucible to fix a direction of a convection flow in a plane orthogonal to an application direction of the horizontal magnetic field in the silicon melt, the horizontal magnetic field being applied so that a central magnetic field line passes through a point horizontally offset from a center axis of the quartz crucible by 10 mm or more.

A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.

A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.

Spatial coordinates of multiple points on an inner surface of a vitreous silica crucible are measured prior to filling raw material in the vitreous silica crucible, and a three-dimensional shape of the inner surface of the vitreous silica crucible using a combination of polygons having vertex coordinates constituted by the respective measured points is specified (S11); a predictive value of an initial liquid surface level of the silicon melt in the vitreous silica crucible is preset (S12); a volume of the silicon melt satisfying the predictive value of the initial liquid surface level is obtained based on the three-dimensional shape of the inner surface of the vitreous silica crucible (S13); a weight of the silicon melt having the volume is obtained (S14); raw material having the weight is filled in the vitreous silica crucible (S15); a dipping control of the seed crystal is performed based on the predictive value of the initial liquid surface level (S17).

Spatial coordinates of multiple points on an inner surface of a vitreous silica crucible are measured prior to filling raw material in the vitreous silica crucible, and a three-dimensional shape of the inner surface of the vitreous silica crucible using a combination of polygons having vertex coordinates constituted by the respective measured points is specified (S11); a predictive value of an initial liquid surface level of the silicon melt in the vitreous silica crucible is preset (S12); a volume of the silicon melt satisfying the predictive value of the initial liquid surface level is obtained based on the three-dimensional shape of the inner surface of the vitreous silica crucible (S13); a weight of the silicon melt having the volume is obtained (S14); raw material having the weight is filled in the vitreous silica crucible (S15); a dipping control of the seed crystal is performed based on the predictive value of the initial liquid surface level (S17).

A CZ silicon ingot is doped with donors and acceptors and includes an axial gradient of doping concentration of the donors and of the acceptors. An electrically active net doping concentration, which is based on a difference between the doping concentrations of the donors and acceptors varies by less than 60% for at least 40% of an axial length of the CZ silicon ingot due to partial compensation of at least 20% of the doping concentration of the donors by the acceptors.

A method of producing silicon single crystal ingot by pulling the silicon single crystal ingot made of an N-region by the CZ method, including: performing an EOSF inspection including a heat treatment to manifest oxide precipitates and selective etching on sample wafer from the silicon single crystal ingot composed of the N-region to measure a density of EOSF; performing a shallow-pit inspection to investigate a pattern of occurrence of a shallow pit; adjusting the pulling conditions according to result of identification of a defect region of the sample wafer by the EOSF and shallow-pit inspections to pull a next silicon single crystal ingot composed of the N-region, wherein in the identification of the defect region, for an N-region, what portion of an Nv-region or Ni-region the defect region corresponds to is also identified.

An apparatus for growing a silicon single crystal according to embodiments includes a chamber including a crucible accommodating silicon melt; a support shaft rotating and lifting the crucible while supporting the crucible; a main heater part for applying heat to the crucible side, the heater disposed beside the crucible; an upper heat insulation member located over the crucible; and upper heater parts located at a lower end portion of the upper heat insulation member, wherein the upper heater parts have diameters different from each other with respect to a center of the crucible, and include a plurality of ring-shaped heaters which are spaced apart from each other. Due to the individually controllable upper heater parts, a uniform thermal environment can be provided for silicon melt accommodated in a crucible, and localized solidification of the silicon melt can be prevented so that the quality of a silicon single crystal and the ingot pulling speed can be readily controlled.

A sheet-forming apparatus including a crucible for holding a melt of material and a solid sheet of the material disposed within the melt, a crystallizer disposed above the crucible and configured to form the sheet from the melt, and an ultrasonic measurement system disposed adjacent the crystallizer, the ultrasonic measurement system comprising at least one ultrasonic measurement device including a waveguide coupled to an ultrasonic transducer for directing an ultrasonic pulse through the melt.