Atomic force microscopic analyses of heavy ion tracks in CR-39

The track evolution for high energy C and Si ions in CR-39 was studied using an atomic force microscope (AFM). The image processing method of AFM observations and the 3-D images of C and Si tracks are reported. The track diameter increased linearly with the amount of bulk etch of CR-39, but the retardation of growth of the track length was observed at the early stage of the etching. As a result, considerable discrepancies between the track sensitivities calculated by using the track diameter and the length appeared especially in the early stage of the etching. The results reported here show that AFM observations are very useful in practical application to the quantitative analysis for minute etch pits in a track detector. (C) 1999 Elsevier Science B.V. All rights reserved.