THE ELECTRICAL-RESISTIVITY OF THIN PD FILMS GROWN ON SI(111)

Thin palladium films are deposited on boron-doped p-type Si(111) single crystals under UHV conditions. The structure is studied in situ by LEED and Auger analysis, in addition the resistivity is measured with the help of a four-probe technique. The resistivity always decreases with increasing film thickness. For films deposited on an oxygen-free silicon surface with a 1 x 1 structure, the decrease mainly occurs at very low thicknesses, then the resistivity approaches a saturation value which is characteristic of a layer-by-layer growth. For films deposited on silicon with oxygen present in the surface, a steep decrease is observed at much higher thicknesses. Island growth is then the dominating factor for the conduction behaviour.