Early stages in thin film metal–silicon and metal–SiO2 reactions under rapid thermal annealing conditions: The rapid thermal annealing/transmission electron microscopy technique

A simple and fast structural characterization technique for thin film solid-phase reactions has been developed, based on a combination of rapid thermal annealing and transmission electron microscopy (the ‘‘RTA/TEM technique’’). The technique is used to investigate fast interfacial reactions in layered Si/Ni/Si, Si/Co/Si, Si/Ti/Si, and SiO2/Ti/SiO2 films. In contradiction to first-phase rules, all three metal–Si systems exhibit nucleation of multiple ‘‘first’’ silicides; under certain conditions, an amorphous (metal+Si) mixture exists prior to this nucleation. The simultaneous study of Si–Ti and SiO2–Ti reactions with RTA/TEM can quickly determine processing ‘‘windows’’ when selective silicidation is required.