Laser-induced desorption from thin films (approx. 500 nm thick) of Cu-phtalocyanine cast from solution on a glass substrate was investigated. The mass-spectra and dependence of desorption intensities on incident irradiation energy were studied by means of time-of-flight mass-spectrometry. 20 ns pulse laser irradiation was used at 532 nm and 1064 nm wavelengths. According to the absorption spectrum of the Cu-phtalocyanine films the wavelengths correspond to bandgap and sub-bandgap excitation of the films, respectively. Desorption of Cu-phtalocyanine molecules, their fragments, including Cu atoms was observed when laser energy exceeded 0.05 J/cm(2) pulse and 0.4 J/cm(2) pulse thresholds in case of the bandgap and the sub-bandgap excitation, respectively. Cu atoms component was the most intensive in the desorption flow. The phenomena observed are discussed in terms of the incident energy absorption in the aromatic system and via the localized states of the Cu-phtalocyanine films under study.

Laser-induced desorption of neutral fragments from the surface of thin organic corbathiene and polythiophene films is studied by means of time-of-flight (TOF) mass-spectrometry. Desorption takes place under laser excitation in the wavelength range corresponding to the pi-absorption band of the organic films. The discussed processes of fragmentation and fragment desorption are stimulated via photo-electronic excitation of the large organic molecules.