Fracture of brittle epitaxial films under the influence of misfit stress

Epitaxial films of brittle materials like the garnets often fracture under the influence of tensile (misfit) stresses. A consideration of the conditions which lead to fracture indicates that cracks will not propagate in a film which is strongly bonded to its substrate unless the film thickness is greater than the Griffith crack length. Predictions based on this condition are in good agreement with all experimental determinations of the circumstances which lead to cracks. © 1972.