Optical and electrical properties of polycarbonate matrices implanted by high energy Cu ions

1 MeV copper ions were implanted in polycarbonate (PC) matrices with fluences ranging from 5 x 10(13) ions cm(-2) to 1 x 10(17) ions cm(-2) in order to modify the optical and electrical properties of the polymer host. Increasing the ion fluence, an increase of the overall absorption and a redshift of the optical band gap were observed, from the initial value of 3.40 eV for the pristine PC to 0.80 eV measured for 1 x 10(17) ions cm(-2). For fluences above 5 x 10(14) ions cm(-2) a broad optical absorption bands at 450-475 nm and 520 nm were observed and, from 1 x 10(16) ions cm(-2), an additional band appeared at 570 nm. Both bands redshift when the fluence is increased. On the contrary, the optical response of the highest fluence sample is characterized by an overall band at 580 nm. The chemical modifications observed in the polymer range from induced -OH stretching, C=O and -C=C- double bonds and -C C and CH triple bonds formation, as the ion fluence increases. The implantation process affects the electrical properties of the polymer leading to a strong reduction in sheet resistance when ion fluence exceeds 5 x 10(16) ions cm(-2). A value of similar to 7.1 x 10(7) Omega/sq has been obtained for the highest fluence, i.e. about 10 order of magnitude lower than the pristine PC. (c) 2013 Elsevier B.V. All rights reserved.