QUANTITATIVE-ANALYSIS OF LOW-ENERGY XE+ ION-BOMBARDMENT DAMAGE OF SI(100) SURFACES USING X-RAY PHOTOELECTRON-SPECTROSCOPY

In situ x-ray photoelectron spectroscopy has been used to analyze the nature and extent of damage to the Si(100) surfaces bombarded with xenon ions in the energy range 0.25-2 keV. Dramatic changes in the Si 2p core levels were found upon ion bombardment. A curve-fitting analysis of the core level shows that an amorphous silicon overlayer is formed on the Xe+ ion bombarded surface. The results indicate that these low-energy Xe+ ions amorphize the surface in a layer-by-layer manner and that the depth of damage increases rapidly for ion doses between 10(13) and 10(15) ions cm-2 . At about 10(15) ions cm-2 the damage depth reaches a saturation for all ion energies studied. The saturated damage depth is found to increase linearly with ion energy.