Patent · US Expired

Tantalum based crucible

US7056383B2 · kind B2 · utility

28Cited by
15References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 13, 2004
Grant dateJun 6, 2006
Priority date
Expiry dateFeb 13, 2024

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC30B35/002
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A crucible is provided that is thermally stable at high temperatures and is suitable for use in the growth of large, bulk AlN, AlxGa1-xN or other nitride single crystals. The crucible is comprised of specially treated tantalum. During the initial treatment, the walls of the crucible are carburized, thus achieving a crucible that can be subjected to high temperatures without deformation. Once the carburization of the tantalum is complete, the crucible undergoes further treatment to protect the surfaces that are expected to come into contact with nitride vapors during crystal growth with a layer of TaN. If the crucible is to be used with a graphite furnace, only the inner surfaces of the crucible are converted to TaN, thus keeping TaC surfaces adjacent to the graphite furnace elements. If the crucible is to be used with a non-graphite furnace, both the inner and outer surfaces of the crucible are converted to TaN.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.