Roughening of Au(111) Surfaces During Ion Beam Erosion: A Scanning Tunneling Microscope and X-Ray Diffraction Study

Abstract

Using Scanning Tunneling Microscopy(STM) and X-ray diffraction(XRD), we have studied the development of surface roughness on Au(111) during 500eV Ar+ ion irradiation at different angles. During normal incidence erosion the surface roughens and pattern formation occurs. The surface morphology is a mixture of mounds and pits superimposed onto a larger structure of channels and valleys. The characteristic spacing between features grows with a power law behavior t27, where t is the amount of time the sample was irradiated, in agreement with previous measurements[l]. At glancing angles, erosion proceeds smoothly, but not in layer-by-layer fashion. Finally, a combination of glancing angle and normal incidence erosion is used to create a rippled morphology

On the stabilization of ion sputtered surfaces

“…Let us first consider the regime of small slope. Here the analysis proceeds as above with the same Ã, B, C defined in (12). As before the sign of the integral hinges on the value of f ′ (bx min ) = −g ′ (x min )/b.…”

“…Uniform ion beam sputter erosion of a solid surface often causes a spontaneously-arising topographic pattern in the surface topography [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33], that can take the form of a one-dimensional corrugation or a two-dimensional array of dots with typical length scales of 10 2±1 nm. Periodic self-organized patterns with wavelength as small as 15 nm [6,15] have stimulated interest in this method as a means of nanofabrication at sub-lithographic length scales [26].…”