Methods for producing single crystal silicon ingots by Continuous Czochralski (CCz) are disclosed. A batch of buffer members (e.g., quartz cullets) is added to an outer melt zone of the crucible assembly before the main body of the ingot is grown. In some embodiments, the ratio of the mass M of the batch of buffer members added to the melt to the time between adding the batch of buffer members to the melt and when the ingot main body begins to grow is controlled such that the ratio of M/T is greater than a threshold M/T.

Methods for producing single crystal silicon ingots by Continuous Czochralski (CCz) are disclosed. A batch of buffer members (e.g., quartz cullets) is added to an outer melt zone of the crucible assembly before the main body of the ingot is grown. In some embodiments, the ratio of the mass M of the batch of buffer members added to the melt to the time between adding the batch of buffer members to the melt and when the ingot main body begins to grow is controlled such that the ratio of M/T is greater than a threshold M/T.

A ScAlMgO.sub.4 monocrystalline substrate that is highly cleavable and that does not easily cause cracking in the GaN film id grown on the substrate and a method for manufacturing such a ScAlMgO.sub.4 monocrystalline substrate are provided. The ScAlMgO.sub.4 monocrystalline substrate has a crystal oxygen concentration of 57 atom % or less as measured by inductively coupled plasma atomic emission spectroscopy analysis.

A ScAlMgO.sub.4 monocrystalline substrate that is highly cleavable and that does not easily cause cracking in the GaN film id grown on the substrate and a method for manufacturing such a ScAlMgO.sub.4 monocrystalline substrate are provided. The ScAlMgO.sub.4 monocrystalline substrate has a crystal oxygen concentration of 57 atom % or less as measured by inductively coupled plasma atomic emission spectroscopy analysis.

A single-crystal pulling apparatus including: a pulling furnace having a central axis; and a magnetic field generation device arranged around the pulling furnace and having superconducting coils, the apparatus applying a horizontal magnetic field to the molten semiconductor raw material, two coil axes in the two pairs of the superconducting coils are included in a single horizontal plane, and when a direction of lines of magnetic force at the central axis of the pulling furnace in the horizontal plane is determined as an X axis, a center angle α having the X axis between the two coil axes is 100 degrees or more and 120 degrees or less. This makes it possible to reduce the height of the coils, to raise the magnetic field center close to the melt surface of the semiconductor raw material, and to obtain a single crystal having a lower oxygen concentration than conventional single crystals.

A single-crystal pulling apparatus including: a pulling furnace having a central axis; and a magnetic field generation device arranged around the pulling furnace and having superconducting coils, the apparatus applying a horizontal magnetic field to the molten semiconductor raw material, two coil axes in the two pairs of the superconducting coils are included in a single horizontal plane, and when a direction of lines of magnetic force at the central axis of the pulling furnace in the horizontal plane is determined as an X axis, a center angle α having the X axis between the two coil axes is 100 degrees or more and 120 degrees or less. This makes it possible to reduce the height of the coils, to raise the magnetic field center close to the melt surface of the semiconductor raw material, and to obtain a single crystal having a lower oxygen concentration than conventional single crystals.

The method of the disclosure for producing a crystal is a method for producing a crystal of silicon carbide and includes a preparation step, a contact step, a first growth step, a heating step, a cooling step, and a second growth step. The preparation step includes preparing a seed crystal, a crucible, and a solution. The contact step includes bringing the seed crystal into contact with the solution. The first growth step includes heating the solution to a temperature in a first temperature range and pulling up the seed crystal with the temperature of the solution kept in the first temperature range to grow a crystal from the lower surface of the seed crystal. The heating step includes heating the solution. The cooling step includes cooling the solution. The second growth step includes further growing the crystal with the temperature of the solution kept in the first temperature range.

The method of the disclosure for producing a crystal is a method for producing a crystal of silicon carbide and includes a preparation step, a contact step, a first growth step, a heating step, a cooling step, and a second growth step. The preparation step includes preparing a seed crystal, a crucible, and a solution. The contact step includes bringing the seed crystal into contact with the solution. The first growth step includes heating the solution to a temperature in a first temperature range and pulling up the seed crystal with the temperature of the solution kept in the first temperature range to grow a crystal from the lower surface of the seed crystal. The heating step includes heating the solution. The cooling step includes cooling the solution. The second growth step includes further growing the crystal with the temperature of the solution kept in the first temperature range.

A method for growing beta phase of gallium oxide (β-Ga.sub.2O.sub.3) single crystals from the melt contained within a metal crucible surrounded by a thermal insulation and heated by a heater. A growth atmosphere provided into a growth furnace has a variable oxygen concentration or partial pressure in such a way that the oxygen concentration reaches a growth oxygen concentration value (C2, C2′, C2″) in the concentration range (SC) of 5-100 vol. % below the melting temperature (MT) of Ga.sub.2O.sub.3 or at the melting temperature (MT) or after complete melting of the Ga.sub.2O.sub.3 starting material adapted to minimize creation of metallic gallium amount and thus eutectic formation with the metal crucible. During the crystal growth step of the β-Ga.sub.2O.sub.3 single crystal from the melt at the growth temperature (GT) the growth oxygen concentration value (C2, C2′, C2″) is maintained within the oxygen concentration range (SC).

The present invention relates a method for controlling a growth interface shape while growing a monocrystal ingot by a Czochralski method, the method including a step of starting a growth of the monocrystal ingot after setting a control condition of a monocrystal growing process so that an interface of the ingot becomes a target shape; a step of deriving a measurement value by measuring a weight of the ingot grown for a predetermined time by means of a load cell disposed on an upper portion the monocrystal ingot; a step of deriving a theoretical value of the weight of the monocrystal ingot through a diameter of the monocrystal ingot measured by a diameter measuring camera disposed outside of a process chamber for a predetermined time and a height of the monocrystal ingot grown for the predetermined time; a step of predicting a growth interface shape of a growing monocrystal ingot by deriving a difference between the measurement value and the theoretical value; and changing process conditions during growth of the monocrystal ingot by comparing the predicted interface shape of the monocrystal ingot with the targeted interface shape of the monocrystal ingot. Therefore, the interface shape of the growing ingot may be predicted during the growing process of the monocrystal ingot, and the process conditions may be controlled to grow the silicon ingot in the targeted interface shape.