The effect of inhomogeneous dopant profiles on the electron energy loss spectra of Si(100)

Surface Plasmon excitations are measured by high resolution electron energy loss spectroscopy (HREELS) on highyln-doped, clean Si(100) wafers. After different annealing cycles at 900°C the plasmon loss shifts to lower loss energy. This effect can be quantitatively described by out-diffusion of the phosphorus dopant. The assumption of diffusion profiles and fits of calculated loss spectra to the experimental data allow a determination of the diffusion constant of phosphorus in silicon.