High temperature protective coating for graphite. PBN has become the material of choice for compound semiconductor crystal growth and wafer processing. PBN coatings also seal and protect graphite from very corrosive atmospheres including most molten metals, all acids, and hot ammonia. PBN is an electrical insulator which exhibits a high degree of anisotropy, e.g. good thermal conductor parallel ("ab") to substrate and thermal insulator through thickness ("c"). Information provided by Momentive Performance Materials, formerly GE Advanced Ceramics. |