Individual twin boundaries in Ag films on Ru(00▪1) were tracked by using low-energy electron microscopy. The twin boundaries, which separate film regions whose close-packed planes were stacked differently, move readily during film growth but relatively little during annealing. The growth-driven motion of twin boundaries occurred as film steps advance across the surface—as a new atomic Ag layer reaches an face-centered cubic twin boundary, the advancing step edge carries along the boundary. This coupling of the microstructural defect (twin boundary) and the surface step during growth could produce film regions over 10µm wide that were twin free.

Twin Boundaries Can Be Moved by Step Edges During Film Growth. W.L.Ling, N.C.Bartelt, K.F.McCarty, C.B.Carter: Physical Review Letters, 2005, 95[16], 166105 (3pp)