Photoluminescence properties of C-60 films deposited on silicon substrate

Photoluminescence (PL) spectra of C-60 films deposited on Si substrates hav e been measured from 10 to 300 K and as a function of laser excitation inte nsity. Recombination of self-trapped excitons and their phonon replicas, as well as X-trap-related emissions, are the main features of the PL spectra. The influence of the deposition parameters, namely deposition rate and sub strate temperature, on the luminescence efficiency of the C-60 films have b een investigated. Low substrate temperature produces a lowering of the PL e fficiency, whereas an increase of the deposition rate causes an increase of the X-trap emission. (C) 2000 Elsevier Science B.V. All rights reserved.