Study on preventing segregation of erbium atoms to a silicon surface by annealing in oxygen atmosphere at high temperature

The damage produced by implantation of Er ions of 400 keV at a fluence of 5 x 1015 ions/cm2 in silicon was investigated by Rutherford backscattering spectrometry with 2.1 MeV He2+ ions with multiple scattering models. It was found that the damage around the Si surface was almost removed after annealing in oxygen and nitrogen atmospheres successively at 1000 deg. C, and only a small portion of the Er atoms segregated to the silicon surface. Most of the Er atoms diffused to deeper depths because of the affinity of Er for oxygen.