Investigation of optical properties of polymers exposed to radiation by high-energy krypton ions

Full text: It's common knowledge that at high-energy ion modification a generation of defects induced by inelastic interaction is observed with formation of nuclear tracks in the bulk of irradiated material. When studying the structure of latent tracks in depth, 'a pile' set of thick polymer films is generally used. Nevertheless, it is rather difficult to maintain the same conditions of track etching for every film. What is more, it is preferable to get some information of continuous spectrum energy variation. For this purpose, absorbing filter as a metal foil of necessary thickness bent in a predetermined law is used in present work. On the surface of polymer films exposed to radiation an extended region is produced with the energy of bombardment particles varying within 0 till 250 MeV range. Owing to this region size which many times exceeds the projected distance, optical properties of ion-implanted polymer films have been studied. Based on performed investigations, it was shown that the character of flight transmission modification of spectrum blue region (420 nm) agrees well with the profile of bent in a parabolic law filter. In this case a decrease of heavy ion energy within 250 till 0 MeV range correlates with an increase of polymer film light transmission from 7 % to a value equal to studied parameter of non-irradiated sample - 35 %. So, optical density of films modified by high-energy krypton ions depends not only on ion fluence, but on their energy. When using absorbing profile filters, the obtained results allow to purposely distribute the implantation energy, and, consequently, to control light transmission of polymer films as promising and competitive materials for manufacture of functional elements of optics and electronics. Undoubtedly, this above- described method will also allow to considerably decrease energy expenses when using acceleration techniques owing to formation of ionic damage ability profiles of materials at single run