A thin (1–3 nm) Ti layer is shown to improve the uniformity and the thermal stability of CoSi2layers grown on Si substrates. The beneficial effect of the Ti(TiN) cap is demonstrated for a variety of CoSi2layers, including Ti‐interlayer mediated epitaxial (TIME) CoSi2/Si(100), polycrystalline CoSi2/Si(100), and CoSi2/polycrystalline Si. The increased uniformity and stability of the silicide layers are speculated to result from reduced surface and interface diffusion during nitrogen and/or vacuum anneals. In the case of TIME CoSi2/Si(100), both the use of a Ti cap and the removal of a metastable Ti4Co4Si7overlayer prior to high‐temperature anneals are found important for the fabrication of uniform, single‐crystal layers. ©1995 American Institute of Physics.