  We deposited thin layers of CdS and ZnS nanoparticles embedded in a
thermoplastic cyclo-olephin copolymer (COC) with elevated optical transparency
and highly bio-compatible. The nanoparticles were obtained by thiolate
precursors previously dispersed in the polymer upon thermal treatment at
temperatures ranging between 200 and 300 Celsius degrees depending on the
desired size. The precursor/polymer solutions were spin coated in order to get
thin films. The samples were mainly characterised by X-ray reflectivity (XRR)
and by High Resolution Transmission Electron Microscopy (HRTEM) analyses. The
HRTEM measurements showed that the nanoparticles have quasi-spherical shape
without evident microstructural defects. The size of the nanoparticles depends
on the annealing temperature, e.g. at 232 Celsius degrees the size of the CdS
nanoparticles is about 4-5 nm.
