ION-IMPLANTATION INDUCED ANOMALOUS SURFACE AMORPHIZATION IN SILICON

Spectroscopic ellipsometry (SE), high-depth-resolution Rutherford back scattering (RBS) and channeling have been used to examine the surface damage formed by room temperature N and B implantation into silicon. F or the analysis of the SE data we used the conventional method of assu ming appropriate optical models and fitting the model parameters (laye r thicknesses and volume fraction of the amorphous silicon component i n the layers) by linear regression. The dependence of the thickness of the surface-damaged silicon layer (beneath the native oxide layer) on the implantation parameters was determined: the higher the dose, the thicker the disordered layer at the surface. The mechanism of the surf ace amorphization process is explained in relation to the ion beam ind uced layer-by-layer amorphization. The results demonstrate the applica bility of spectroscopic elipsometry with a proper optical model. RBS, as an independent cross-checking method supported the constructed opti cal model.