Surface sensitivity effects with local probe scanning Auger-scanning electron microscopy

This letter concentrates on a quantitative description of surface roughness effects on Auger peak-line profiles for pure and alloyed specimens. The na nometer lateral electron probe size of the order of 10 nm yielded peak-line profiles that capture surface topology variations down to nanometer-length scales. Surface roughness leads to peak-intensity fluctuations, which are described within the weak roughness limit by a simple form, I(r)approximate to I-av[1 + beta h(r)]. I-av is the average peak intensity, h(r) represent s the roughness fluctuation along a lateral in-planar distance r, and beta is a constant (< 1). In addition, analyses of the peak-difference correlati on function I-z(r)=<\ I(r)-I(0)\(2)>(1/2) showed a power-law behavior I-z(r )proportional to r(alpha) with alpha ranging between 0.7 and 1 at small-len gth scales, i.e., for r much less than xi, with xi a peak correlation lengt h that was comparable to average specimen cluster sizes. (C) 1999 American Institute of Physics. [S0003-6951(99)04534-9].