Geometric factors in f. c. c. and b. c. c. metal–on–metal epitaxy IV. Deposits of Rh, Ir, Pd and Pt on (001)W and (001)Mo

Abstract

Abstract Deposits of Rh, Ir, Pd and Pt have been formed by condensing the metal vapour in ultra-high vacuum onto (001)W and (001)Mo substrates held at a temperature, T s in the range 300–1200 K. At T s≃300K, deposits are oriented (001)d∥(001)s† but are not preferentially aligned. At T s≃500K, they contain equal proportions of grains oriented (001)d∥(001)s with [Π0]d∥[010]s and (110)d ∥(001)s with [1Π]d parallel to [Π0]s or [Π0]s. The domains of the latter orientation are heavily faulted exclusively parallel to (110)d. At T s 700 K, deposits consist entirely of faulted (110) epitaxed grains. The structure of (001) epitaxed grains is always f. c. c. whereas that of (110) epitaxed grains is f. c. c. bolow 700 K, f. c. c. + h. c. p. at 700 K, and entirely h. c. p. above 1000 K. The results confirm the general applicability of the growth model developed in Parts I and II. On the basis of this model, predictions are made for all f. c. c.-b. c. c. metal pairs. The model is further applied to deposits of h. c. p...