Process for producing single crystals

A method of producing single crystals in an apparatus comprising a chamber containing a crucible for containing a melt from which a single crystal is grown, a heating element for heating the melt, a pulling mechanism for growing the single crystal after contacting the melt with a seed crystal, a protective gas inlet pipe arranged to release heat by thermal conduction with the chamber, the protective gas inlet pipe extending downwardly into the chamber and surrounding the pulling mechanism, supporting components on a lower end of the protective gas inlet pipe, and a heat resistant and heat insulating component supported on the lower end of the protective gas inlet pipe by the supporting components, the heat resistant and heat insulating component surrounding a pulling zone of the single crystal above the melt in the crucible, the method comprising:

• forming a melt of material in the crucible by heating the material with the heating element;
• growing a single crystal by contacting the melt with the seed crystal and pulling the single crystal from the melt with the pulling mechanism;
• and
• providing a small temperature gradient along the single crystal with the heat resistant and heat insulating component and providing a high temperature gradient along the single crystal with the protective gas inlet pipe.

A method of producing single crystals in an apparatus comprising a chamber containing a crucible for containing a melt from which a single crystal is grown, a heating element for heating the melt, a pulling mechanism for growing the single crystal after contacting the melt with a seed crystal, a protective gas inlet pipe arranged to release heat by thermal conduction with the chamber, the protective gas inlet pipe extending downwardly into the chamber and surrounding the pulling mechanism, supporting components on a lower end of the protective gas inlet pipe, and a heat resistant and heat insulating component supported on the lower end of the protective gas inlet pipe by the supporting components, the heat resistant and heat insulating component surrounding a pulling zone of the single crystal above the melt in the crucible, the method comprising:

• forming a melt of material in the crucible by heating the material with the heating element;
• growing a single crystal by contacting the melt with the seed crystal and pulling the single crystal from the melt with the pulling mechanism;
• and
• providing a small temperature gradient along the single crystal with the heat resistant and heat insulating component and providing a high temperature gradient along the single crystal with the protective gas inlet pipe, the supporting components comprising a plurality of circumferentially spaced-apart components extending between an outer periphery of the protective gas inlet pipe and an upper end of the heat resistant and heat insulating component.

A method of producing single crystals in an apparatus comprising a chamber containing a crucible for containing a melt from which a single crystal is grown, a heating element for heating the melt, a pulling mechanism for growing the single crystal after contacting the melt with a seed crystal, a protective gas inlet pipe arranged to release heat by thermal conduction with the chamber, the protective gas inlet pipe extending downwardly into the chamber and surrounding the pulling mechanism, supporting components on a lower end of the protective gas inlet pipe, and a heat resistant and heat insulating component supported on the lower end of the protective gas inlet pipe by the supporting components, the heat resistant and heat insulating component surrounding a pulling zone of the single crystal above the melt in the crucible, the method comprising:

• forming a melt of material in the crucible by heating the material with the heating element;
• growing a single crystal by contacting the melt with the seed crystal and pulling the single crystal from the melt with the pulling mechanism;
• and
• providing a small temperature gradient along the single crystal with the heat resistant and heat insulating component and providing a high temperature gradient along the single crystal with the protective gas inlet pipe, an upper end of the heat resistant and heat insulating component being spaced vertically below the lower end of the protective gas inlet pipe.