Cone formation on Ag surface bombarded by Ar at oblique incidence

Abstract

Sputter-induced topographical modifications of a silver surface bombarded by mass-analysed ions of 30keV 4°Ar ÷ obtained from an electromagnetic isotope separator incident at an angle of 58 ° was studied. Analysis of the silver surface by scanning electron microscopy showed that most of the bombarded area was covered with features similar to corrugated terrace steps, sharp and fine cones, and pyramids. The underlying mechanism for formation of such features is discussed. The method of formation of such sharp cones produced by ion bombardment will increasingly find applications in the formation of fine tips required in scanning probe and field emission microscopy.