The Schottky-barrier height of Al/silicide layers to n-type Si was measured as a function of annealing temperature with CoSi2, MoSi2, and PtxNi1−xSi for the silicide. The barrier heights before annealing were 0.64, 0.69, and 0.74 eV, respectively, in the systems mentioned. On annealing, these values changed first due to Al diffusion through the silicide and compound formation and subsequently by Si precipitation. This change took place at a higher temperature when Al/Si was used. No change was found up to 500 °C when a thin W or Ti/W layer was used between the silicide and Al.