Local identification and mapping of the C49 and C54 titanium phases in submicron structures by micro-Raman spectroscopy

Abstract

In this letter, it is shown that micro-Raman spectroscopy allows easy, nondestructive determination of the C49 and C54 phase of titanium silicide with μm resolution within single structures with area dimensions down to 1×1 μm2 and along isolated line structures with widths down to 0.25 μm. The micro-Raman spectroscopy technique is used to study isolated 0.25–5-μm-wide TiSi2 lines with thicknesses as small as 16 nm that are formed in both crystalline Si and polycrystalline Si. The phase mapping ability of the technique is demonstrated on several 80-μm-long, 0.35-μm-wide TiSi2 lines that are part of four-terminal line resistance devices created using complementary metal–oxide–semiconductor processing.