STABILIZATION OF CUBIC CRN0.6 IN CRN0.6 TIN SUPERLATTICES/

A transmission electron microscopy study of CrN0.6/TiN superlattices d eposited by reactive magnetron sputtering is described. The stable str ucture of CrN0.60 is hexagonal, but high resolution transmission elect ron microscopy images of the superlattices showed that CrN0.6 layers l ess than or equal to 10 nm thick were cubic, while 50 nm thick layers were hexagonal. That is, the cubic CrN structure was ''epitaxially sta bilized'' by the cubic TiN, with which there is a 2.4% lattice mismatc h. The superlattices with hexagonal CrN0.6 showed high strains and def ect densities within approximate to 5 nm of each interface, presumably due to the 5.4% volume decrease associated with the cubic-to-hexagona l transformation. The effect of this strain on the transformation is d iscussed. (C) 1998 American Institute of Physics.