Interface catalytic effect: Cr at the Si(111)-Au interface

Synchrotron radiation photoemission studies of the effect of Cr interlayers on Si(111)-Au interface reaction show that Cr concentrations below 1×{}10¹⁵ atoms/cm² retard Si-Au intermixing, concentrations between 1 and 7.5×{}10¹⁵ atoms/cm² promote Si-Au intermixing, and concentrations in excess of 8×{}10¹⁵ atoms/cm² sharply reduce intermixing. These variations are shown to depend on the three formation stages of the Si-Cr junction. Cr itself is shown only to be indirectly involved in the Si-Au reaction and Si is to be the only moving species.