Some electrochemical etching studies on the registration of alpha particle tracks in polycarbonate

Abstract The registration of alpha particle tracks was studied in 250 μm thick polycarbonate foils using the electrochemical etching (ECE) method. The etchant was a mixture of ethanol, potassium hydroxide, and water at 25°C and the effects of concentration and etching duration were also investigated at different alpha energies by applying a field strength of 32 kV/cm at 2 kHz frequency. The alpha tracks were registered efficiently with an upper energy threshold of about 2.1 MeV having track diameters of up to 230 μm which are easily observable by the unaided eyes. The etching duration and the etchant concentration showed strong effects on the efficiency, track diameter, and the energy thresholds. A mixture of 15 g KOH + 40 g C 2 H 5 OH + 45 g H 2 O was found to be an optimum mixture which is the same as commonly used in conventional etching called PEW solution. In conclusion, alpha particle tracks can be efficiently registered in polycarbonate and it is applicable to a number of health physics and radiation research applications.