Growth of epitaxial CoSi 2 films on Si(1 0 0) substrates through direct solid phase reaction between crystalline Co films and Si substrates

Abstract

Epitaxial CoSi 2 films were grown on Si(1 0 0) substrates via direct solid-phase reaction between crystalline (0 0 2) textured Co films and the Si substrates. Rutherford backscattering/channeling spectrometry and high-resolution transmission electron microscopy were performed to evaluate the epitaxial quality of the CoSi 2 films. A good channeling χ min value of 20% was measured for the CoSi 2 films formed after rapid thermal annealing at 850°C, which is comparable to that of the CoSi 2 films obtained by Ti-interlayer mediated epitaxy (TIME). Similar with TIME, the intermediate phase of Co 2Si was skipped in this case. The concept of “thermodynamic barrier” has been employed to explain the improvement in the epitaxy of CoSi 2 films compared with the reaction between amorphous Co films and Si substrates.