Electronic structure of nickel silicide in subhalf-micron lines and blanket films: An x-ray absorption fine structures study at the Ni and Si L3,2 edge

Abstract

We report a Ni and Si L3,2-edge x-ray absorption near edge structures (XANES) study of nickel–silicon interaction in submicron (0.15 and 0.2 μm) lines on a n-Si(100) wafer as well as a series of well characterized Ni–Si blanket films. XANES measurements recorded in both total electron yield and soft x-ray fluorescence yield indicate that under the selected silicidation conditions, the more desirable low resistivity phase, NiSi, is indeed the dominant phase in the subhalf-micron lines although the formation of this phase is less complete as the line becomes narrower and this is accompanied by a Ni rich surface.