We demonstrate the use of Raman spectroscopy with a multichannel detector to characterize the growth of PtSi on Si(100). The vibrational modes of surface silicide layers as thin as 10 A˚ and PtSi layers less than 40 A˚ thick buried under 140 A˚ of Pt have been observed without the need for any special sample geometry for signal enhancement. The Raman spectra can identify the silicide layer, estimate its thickness, and demonstrate its crystalline quality. This can be done on an arbitrary substrate, in air and without any special sample preparation.