The Use of Surface Grinding and Polishing to Remove

A time-efficient surface grinding and polishing procedure was developed to remove noise pitting associated with the etching of CR-39. CR-39 is a solid-state nuclear track detector used to measure and analyze ions produced by fusion implosions on the OMEGA and OMEGA EP laser systems. Using CR-39 thickness measurements acquired during the grinding process, surface removal rates of 68 µm/min and 5 µm/min were determined for 15-µm and 9-µm-grade abrasive pads, respectively. Removing 3-4 µm of surface material eliminated noise pits, as well as shallow 1-MeV and 2-MeV proton-induced pits. Exposing a CR-39 sample to UV light before etching was investigated as a method to deepen shallow data pits. CR-39 exposure to UV light for 48 hours increased 1-MeV and 2-MeV proton pit depth. The combination of CR-39 UV exposure and surface grinding and polishing was shown to eliminate noise pits while preserving data pits.