Development of a new approach to simulate a particle track under electrochemical etching in polymeric detectors

A numerical approach based on image processing was developed to simulate a particle track in a typical polymeric detector, e.g., polycarbonate, under electrochemical etching. The physical parameters such as applied voltage, detector thickness, track length, the radii of curvature at the tip of track, and the incidence angle of the particle were considered, and then the boundary condition of the problem was defined. A numerical method was developed to solve Laplace equation, and then the distribution of the applied voltage was obtained through the polymer volume. Subsequently, the electric field strengths in the detector elements were computed. In each step of the computation, an image processing technique was applied to convert the computed values to grayscale images. The results showed that a numerical solution to Laplace equation is dedicatedly an attractive approach to provide us the accurate values of electric field strength through the polymeric detector volume as well as the track area. According to the results, for a particular condition of the detector thickness equal to 445 μm, track length of 21 μm, the radii of 2.5 μm at track tip, the incidence angle of 90°, and the applied voltage of 2080 V, after computing Laplace equation for an extremely high population of 4000 × 4000 elements of detector, the average field strength at the tip of track was computed equal to 0.31 MV cm−1 which is in the range of dielectric strength for polymers. The results by our computation confirm Smythe’s model for estimating the ECE-tracks.

► A numerical approach is introduced to study electrical mechanism governing ECE.
► Laplace equation is solved numerically to simulate a singular track under ECE.
► Distributions of voltage and field strength around the ECE track are obtained.
► Applying an image processing approach, computed values are converted to images.
► Results are in agreement with previous experiments and confirm Smythe equation.