Crucible of pyrolytic boron nitride for molecular beam epitaxy

摘要

Disclosed is a crucible of pyrolytic boron nitride (PBN) for molecular beam epitaxy for melting of the source material, with which the troubles due to adhering of the molten source material in the form of drops caused on the quality of the epitaxial layer can be greatly decreased. Namely, the inner surface of the crucible is free from pits or other irregularities responsible to the adhering of the melt when the growth plane, which can be exposed by stripping of the surface layer of 0.50 mm thickness by cleavage, has a surface roughness Ra not exceeding 2.0 mu m and Rmax not exceeding 18 mu m. Such a PBN crucible can be prepared by the CVD method to deposit PBN on the surface of a graphite core of which the surface roughness Ra does not exceed 2 mu m.