Surface characteristics of nitrogen ion implanted CR-39 polymer: RBS studies

This paper investigates the surface characteristics of nitrogen ion implanted CR-39 polymer. The specimens were implanted with 100 keV N+ beam to various fluences of 1 x 10(15), 1 x 10(16) and 2 x 10(16) ions cm(-2). The ion implantation induced modifications in these specimens were analyzed by Rutherford Backscattering Spectrometry (RBS) and UV-Visible spectroscopy. RBS studies reveal that the structure of the virgin CR-39 specimen has been modified completely after N+ implantation. The spatial distribution in the form of carbonization, projected range, retained dose and atomic concentration of implanted nitrogen have been estimated using RBS spectra. RUMP analysis revealed that for the implanted specimen at fluence 2 x 10(16) N+ cm(-2), the carbon concentration increases from 32 at.% to 43 at.% and oxygen concentration from 19 at.% to 26 at.% respectively near the surface. This increase in the concentration of carbon points towards the carbonization in the implanted layers. Furthermore, UV-Visible transmission spectra demonstrate that for higher fluences, almost complete UV region is blocked; making CR-39 a viable functional material for UV blocking devices.