SUBMICROSCOPIC THEORY FOR THE CHARGE CHANGING PROCESS AND GENERALIZEDCHEMICAL ETCHING VELOCITY

We report three theoretical methods which yield, by means of a compute r program, the theoretical submicroscopic and microscopic track profil es corresponding to normal incidence ions for velocities of chemical a ttack which vary with the position on the incidence axis (x) of the io n and the perpendicular distance measured on the y axis. The program c an simulate tracks for cases in which there are weak or sharp fluctuat ions in the physical damage. These fluctuations may come statistical c hanges in the damage or changes in the charge state of the incident io n. We report here an alternative solution for problems identified in e arlier studies (e.g. G. Somogyi and S.A. Slazay, Nucl. Instr. and Meth . 109 (1973) 211 and R. Mazzei et al., Nucl. Instr. and Meth. B9 (1985 ) 163) for the microscopic and submicroscopic tracks, respectively.