Surface structure of epitaxial Pd2Si thin films

Abstract
The surface structure of Pd2Si thin films epitaxially grown on clean Si (111) 7×7 surfaces has been studied by low‐energy electron diffracton (LEED) and Auger electron spectroscopy (AES). Heat treatment in the range of 200–600 °C causes surface segregation of elementary Si over a Pd2Si (0001) surface and produces a reconstructed 3×3 superstructure of Pd2Si. A nonreconstructed Pd2Si‐1×1 surface is produced after removing the segregated Si layer by Ar ion beams and its ordering is found to be not damaged by ion sputtering. A possible cause for the thermally induced Si segregation is also examined experimentally and discussed.