Ion energy thresholds and stability of cubic boron nitride

Boron nitride (BN) film growth of mass selected B and N ion deposition has been investigated in a wide range of ion energies. We observed an ion energy window for the cubic BN (c-BN) growth between 75 eV and at least 15/20 keV. The observed low energy threshold for the growth of c-BN is lower than the c-BN nucleation threshold and fits well to the cylindrical spike model. On the high-energy side, c-BN growth was achieved using 15 keV nitrogen and 20 keV boron ions. Additionally, we studied the stability of c-BN under ion irradiation. These studies showed that cubic boron nitride is extremely stable under ion irradiation. It remains stable under nitrogen and argon ion irradiation with energies between 10 and 30 keV up to fluences approximately 10(17) cm(-2). However, if the c-BN/t-BN interface is irradiated, a complete transition to sp(2)-bonded BN already occurs at a low ion fluence of 10(16) cm(-2). (C) 2003 Elsevier Science B.V. All rights reserved.