On the atomic structure of the Pd₂Si/(111)Si interface

Abstract

The structure of the epitaxial Pd₂Si/(111)Si interface has been investigated by transmission electron microscopy (TEM). Lattice imaging and conventional TEM on plan-view specimens show that the Pd₂Si grains are often misoriented, by typically 4° → 7°, from the epitaxial relation of (0001)Pd₂Si//(111)Si, [1010]Pd₂Si//[011]Si. Quantitative texture measurements made by taking convergent-beam diffraction patterns from areas containing individual Pd₂Si grains show that misorientations are mostly described by tilting about <110> directions in the film plane. Lattice imaging in (100) cross-sectional samples reveals more clearly the nature of the Pd₂Si/(111)Si interface and also shows that individual Pd₂Si grains may be considerably bent. The origin of the grain misorientations and their significance in understanding the atomic structure of the Pd₂Si/(111)Si interface is discussed.