Investigation on stress evolution in boron nitride films

Boron nitride films have been grown by ion beam assisted deposition (IBAD) using a Kaufman ion source and an electron beam evaporator. Cantilevers mad e from [100] Si have been used as substrates. Instantaneous stress data are derived from dynamic simultaneous measurement of cantilever bending and fi lm thickness during growth. The instantaneous stress in t-BN lavers is foun d to increase with film thickness and to be in the range between 1.6 and 4. 2 GPa. At the nucleation of c-BN the stress increases up to approximately 1 0 GPa and remains constant during c-BN growth. Correlations between the ion to atom arrival ratio and the Ar/N-2 ratio and the instantaneous stress ar e discussed. The stress relaxation during Ar+-ion post-implantation has bee n measured. (C) 2000 Elsevier Science S.A. All rights reserved.