Pt-doped Ni-silicide films formed by pulsed-laser annealing: Microstructural evolution and thermally robust Ni1-xPtxSi2 formation

摘要

Pulsed-laser annealing (PLA) was performed on a preformed Pt-doped Ni-rich silicide film (Ni2Si phase), and its microstructural and phase evolution were studied from submelting to melting condition by varying the laser power density (P). Vertically nonuniform compositional profile with an interfacial intermixing was observed under a solid state reaction regime (P < 400 mJ/cm(2)) due to a limited atomic diffusion. At higher P condition, melting/resolidification occurred with a continuous increase in the Si concentration, and various microstructures of the film evolved with increasing P: amorphous structure and nucleation/growth of NiSi and NiSi2 phases form in that order on the Si interface. Lastly, by applying additional rapid thermal annealing on the polycrystalline mixture of NiSi and NiSi2 phases formed by PLA, a uniform Pt-doped NiSi2 film with strong epitaxial growth tendency on the Si(001) substrate and high thermal stability (up to 900 degrees C) was synthesized. (C) 2019 Elsevier B.V. All rights reserved.