CHEMICAL-VAPOR-DEPOSITION OF PYROLYTIC BORON-NITRIDE FROM BORAZINE

Pyrolytic boron nitride coatings were prepared by chemical vapor depos ition in the B3N3H6-N-2 system at temperatures from 1300 to 1800 degre es C and total pressures in the system from 10(2) to 10(3) Pa. The dep osition rate was found to be diffusion-controlled The structure of the resultant materials was characterized by IR spectroscopy. The CVD of pyrolytic boron nitride from borazine allows one to reduce the deposit ion temperature in comparison with conventional systems and to obtain dense, stoichiometric coatings containing a large amount of the hexago nal phase at deposition rates high enough for practical application.