Raman Study of Low-Temperature Formation of Nickel Silicide Layers

Low-temperature formation processes of Ni silicide were studied by Raman scattering and cross-sectional transmission electron microscopy (TEM) using Si wafer samples deposited with thin Ni layers. Comparisons were made between two annealing methods; cold wall, lamp based rapid thermal process (lamp RTP) and a hot wall chamber RTP system. . The TEM and Raman observations showed good agreement on the Ni silicidation scheme at the Ni/Si interface. It is shown that Raman scattering spectroscopy is a convenient, non-contact and non-destructive characterization tool to probe and investigate the Ni-silicide formation process in the top nm-order surface of metal/Si contact, as well as to monitor the grain size variation of the silicides and residual stress in the Si wafer