Photoluminescence of composite ceramics derived from polysiloxanes and polycarbosilanes by ion irradiation

Polysiloxanes and polycarbosilanes films were irradiated with increasing fluences of C or Au ions and changes of their photoluminescence (PL) spectra were correlated to structural transformations, assessed by means of ion beam analyses, Raman, XPS and FTIR. They exhibit a strong yellow emission when the energy transferred by the ions to electron shells of target atoms is within the range of 20–60 eV/atom, due to the segregation of C into clusters embedded in an amorphous SixOyCyHz matrix. For larger energy transfers and for pyrolized films, the photoluminescence shifts towards red then vanishes, because of the growth and percolation of the quantum dots.