MODEL OF ION KNOCK-ON MIXING WITH APPLICATION TO SI-SIO2 INTERFACE STUDIES

We have developed an ion knock-on mixing model which yields quantitative predictions of the broadening observed in sputter profiling experiments. The model is based on an analogy to thermal diffusion theory. Interface widths and peak widths are seen to broaden in an rms fashion with a broadening factor W which is inversely proportional to the square root of the sputtering yield. We have also performed Auger sputter profiling experiments to examine the broadening of the Si-SiO//2 interface as a function of ion energy for Ne** plus , Ar** plus , and Xe** plus bombardment. The experimental results are consistent with the mixing model.