GROWTH-MECHANISM OF A AG CRYSTAL PARTICLE CONTAINING A TWIN PLANE GROWN ON A MO(110) SURFACE

We have studied the growth of vapour deposited Ag particles on a Mo(110) surface heated at 400 degrees C using a method of ''in-situ'' observation by scanning electron microscopy (SEM). The shape of almost all Ag particles showed a quasi-Wulff polyhedron of cubo-octahedron truncated by (100) planes, but for the small number of particles multiply twinned particles of a regular icosahedron were observed. Otherwise particular shapes of (111) trigonal bipyramid truncated by (100) planes were observed in rare cases. By successive observation of the growth of these particles, it was clarified that they grew as bicrystal containing a twin plane. The growth process of the particle is described in detail. Such singly twinned particles on the substrate were observed for the first time in the present study and are important as an origin of twins in continuous films.