To provide a single crystal production apparatus capable of efficiently producing a single crystal of relatively high quality, by cooling a melting zone, the device including: a heating part that forms the melting zone from a raw material by irradiation of light; and a supporting part that supports the melting zone in a non-contact manner.

To provide a single crystal production apparatus capable of efficiently producing a single crystal of relatively high quality, by cooling a melting zone, the device including: a heating part that forms the melting zone from a raw material by irradiation of light; and a supporting part that supports the melting zone in a non-contact manner.

A lasing medium having a tailored dopant concentration and a method of fabrication thereof is disclosed. The lasing medium has a single crystal having a continuous body having a selected length, wherein the crystal comprises dopant distributed along the length of the body to define a dopant concentration profile. In one embodiment, the dopant concentration profile results in a uniform heating profile. A method of fabricating a laser crystal having a tailored dopant concentration profile includes arranging a plurality of polycrystalline segments together to form an ingot, the polycrystalline segments each having dopant distributed, providing a crystal seed at a first end of the ingot, and moving a heating element along the ingot starting from the first end to a second end of the ingot, the moving heating element creating a moving molten region within the ingot while passing therealong.

A lasing medium having a tailored dopant concentration and a method of fabrication thereof is disclosed. The lasing medium has a single crystal having a continuous body having a selected length, wherein the crystal comprises dopant distributed along the length of the body to define a dopant concentration profile. In one embodiment, the dopant concentration profile results in a uniform heating profile. A method of fabricating a laser crystal having a tailored dopant concentration profile includes arranging a plurality of polycrystalline segments together to form an ingot, the polycrystalline segments each having dopant distributed, providing a crystal seed at a first end of the ingot, and moving a heating element along the ingot starting from the first end to a second end of the ingot, the moving heating element creating a moving molten region within the ingot while passing therealong.

Granular silicon which is especially useful in reducing dislocations and gas inclusions of single crystals prepared therefrom is produced by a heat treatment in which a process gas flowing through a plasma chamber heats granular silicon, and the heated granular silicon is transported counter-currently through the plasma chamber, melting an outer periphery of the granular silicon, which then recrystallizes, producing an exterior with a lower concentration of crystal grains than the interior of the granules.

Granular silicon which is especially useful in reducing dislocations and gas inclusions of single crystals prepared therefrom is produced by a heat treatment in which a process gas flowing through a plasma chamber heats granular silicon, and the heated granular silicon is transported counter-currently through the plasma chamber, melting an outer periphery of the granular silicon, which then recrystallizes, producing an exterior with a lower concentration of crystal grains than the interior of the granules.

A device for producing a single crystal by crystallizing the single crystal in a melt zone, comprising a housing, an inductor for generating heat in the melt zone, a reheater which surrounds and applies thermal radiation to the crystallizing single crystal, and a separating bottom which delimits downward an intermediate space between the reheater and a wall of the housing at a lower end of the reheater.

A device for producing a single crystal by crystallizing the single crystal in a melt zone, comprising a housing, an inductor for generating heat in the melt zone, a reheater which surrounds and applies thermal radiation to the crystallizing single crystal, and a separating bottom which delimits downward an intermediate space between the reheater and a wall of the housing at a lower end of the reheater.

A single crystal is grown in a float zone which is inductively heated and the crystallizing single crystal is rotated in a direction of rotation which is periodically reversed at intervals in accordance with an alternating plan, wherein a dwell time during which the single crystal is in a state of rest because of the reversal of the direction of rotation is limited to no more than 60 ms.

A single crystal is grown in a float zone which is inductively heated and the crystallizing single crystal is rotated in a direction of rotation which is periodically reversed at intervals in accordance with an alternating plan, wherein a dwell time during which the single crystal is in a state of rest because of the reversal of the direction of rotation is limited to no more than 60 ms.