P-DERIVED VALENCE STATES AT THE REACTIVE GAP(110)/YB INTERFACE VIA P L2,3VV AUGER LINE-SHAPE SPECTROSCOPY

We report on the evolution of the P L2,3 VV Auger line shape with increasing Yb deposition onto the GaP(110) surface. Strong affinity with Si L2,3 VV profiles measured from the Si(111)/Yb interface and nearly-d0 metal silicides (Ca silicides, Gd silicides) is pointed out and fruitfully exploited to model the character of the P 3p-derived valence states in the Yb phosphidelike reaction products. The chemical bond is thus ascribed mainly to the formation of P 3p - Yb 5d hybrids.