Formation of a palladium-silicon interface by silane chemical vapor deposition on Pd(100)

The utility of chemical vapor deposition of silicon from silane gas as a potential route to interfaces has been investigated on Pd(100) using low-energy electron diffraction and scanning tunneling microscopy. Initial adsorption at room temperature leads to the formation of amorphous palladium silicide/silicon surface layer. Annealing to 650 K after low silane exposure (< 5 L) results in subsurface diffusion of silicon with concomitant ejection of palladium atoms. Some surface silicide features also remain intact. Larger exposures (>5 L) at room temperature, followed by 650 K anneal, result in formation of a crystalline (root 13 x root 13R33.7 degrees silicide reconstruction. This palladium silicide phase is thought to be of Pd3Si stoichiometry.