Patent ID: 11939696
Assignee: CRYSTAL SYSTEMS CORPORATION
Field: Surface technology, coating (Chemistry)
Classification: CPC C | IPC C

Claim 16:
17. A thin plate-shaped single-crystal production method comprising at least:
a melting step of melting an upper surface of a raw material lump for production of a thin plate-shaped single crystal by irradiating the upper surface of the raw material lump for the production of the thin plate-shaped single crystal with an infrared ray using an infrared ray irradiation apparatus;
a growing step of starting growth of a single crystal from a lower surface of a thin plate-shaped seed single crystal by immersing the lower surface of the thin plate-shaped seed single crystal in a melt using an elevator apparatus, the melt being formed on the upper surface of the raw material lump for the production of the thin plate-shaped single crystal in the melting step; and
a continuous production step of continuously producing the thin plate-shaped single crystal by pulling upward the thin plate-shaped seed single crystal from which the growth of the single crystal has been started in the growing step,
wherein, in the melting step, the infrared ray emitted from the infrared ray irradiation apparatus is a laser beam, and
wherein a shape of an irradiation area irradiated with the laser beam is a hollow quadrangular shape elongated in a horizontal direction, and a circumferential area of the upper surface of the raw material lump for the production of the thin plate-shaped single crystal is irradiated with the laser beam such that the hollow quadrangular irradiation area is formed in the circumferential area of the upper surface, the circumferential area excluding a central portion of the upper surface.