Abstract
Focused ion beam implantation of Si(++) was used to write defined surface damage/implant patterns into n-type GaAs (100) and Si (100) substrates. These implant sites represent initiation sites for dissolution processes when electrochemically polarized in HCl or HF electrolytes, respectively. Selective dissolution within the patterns is achieved if anodic polarization of the n-type material is carried out in the dark at potentials below (cathodic to) the onset of dissolution potential of the unimplanted surface. Uniform etching within the implanted region takes place, when local electropolishing conditions are established. Thus, highly defined etch patterns, e.g., lines, gratings, or pits, can be produced in the submicron range. The depth of the etched patterns corresponds to the implant/damage profile created in the implantation process and etch stop occurs at less reactive crystal planes. (C) 1998 American Institute of Physics. [S0003-6951(98)00244-7].