Phase transformation of AlN in AlN/VN nanomultilayers and its effect on the mech anical properties of films

AlN/VN nanomultilayers were prepared by reactive magnetron sputtering method. Th e effect of modulation period on the microstructure and mechanical properties of AlN/VN nanomultilayers were studied in this work. The results show that AlN exi sts in metastable cubic structure (c-AlN) at small modulation period and forms c oherent epitaxial grown superlattice with VN. At larger modulation periods, AlN transforms from cubic structure to stable hexagonal structure (h-AlN),and the na nomultilayers form a “brick-wall” structure with nanometer grains. The discuss ion shows that the template effect of VN is beneficial to the growth of c-AlN, b ut cannot increase its critical thickness remarkably.