The room temperature, photoluminescent properties of manganese‐doped zinc sulfide films deposited by spray pyrolysis are reported. These films were deposited on Pyrex glass substrates at atmospheric pressure using air as a carrier gas. All films were polycrystalline with a wurtzite (hexagonal) structure. The manganese doping was achieved by mixing MnCl₃ with the starting solution to deposit ZnS. The photoluminescence spectra was measured at room temperature as a function of the different deposition parameters and the Mn concentration. Besides the characteristic light emission associated with Mn impurities in a ZnS matrix, a peak associated with the self‐activated emission was also observed under certain deposition conditions (low substrate temperatures and/or long deposition times). The presence of chlorine impurities in the films is suggested to be associated with this emission. The Mn luminescence presents a quenching effect with the Mn concentration. This quenching effect is similar to the one reported on films deposited by other techniques. The light emission at this center has an activation energy of 0.71±0.05 eV with the deposition temperature. This energy is proposed to be related with the energy required by the Mn atoms to find a proper site during the growth process to form a Mn²⁺ center.

Amorphous gallium oxide thin films were prepared by the ultrasonic spray pyrolysis method using gallium acetylacetonate as source material and water as oxidizer. Samples annealed at <mml:math display="inline"><mml:mn>850</mml:mn><mml:mo>°</mml:mo><mml:mo>C</mml:mo></mml:math>850°C during 1 h show the crystalline β-phase of <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">Ga</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mo>O</mml:mo><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:mo>.</mml:mo></mml:math>Ga2O3. Rutherford backscattering results indicate that both as-deposited and annealed films have the stoichiometric chemical composition without incorporation of carbon impurities. Infrared (IR) spectroscopic measurements show that there is no incorporation of O-H and Ga-OH radicals in any of the studied films. The IR spectra for amorphous films show a broad absorption band from 400 to <mml:math display="inline"><mml:mn>900</mml:mn><mml:mo> </mml:mo><mml:msup><mml:mi mathvariant="normal">cm</mml:mi><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup><mml:mo>,</mml:mo></mml:math>900 cm−1, typical for some amorphous metallic oxides. Meanwhile, for the annealed films the IR spectra show well-defined peaks located at 450 and <mml:math display="inline"><mml:mn>670</mml:mn><mml:mo> </mml:mo><mml:msup><mml:mi mathvariant="normal">cm</mml:mi><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math>670 cm−1 related to the β-phase of <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">Ga</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mo>O</mml:mo><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:mo>.</mml:mo></mml:math>Ga2O3. The refractive index of the films shows a strong change from 1.846 for the amorphous films to 1.935 for the annealed ones. The optical bandgap energy values are 4.94 eV for the as-deposited films and 4.99 eV for the annealed films. All these changes are associated with a different microstructure of the annealed films. © 2001 The Electrochemical Society. All rights reserved.

Semiconducting thin films were grown on quartz substrates and crystalline silicon wafers, using dilithium phthalocyanine and the organic ligands 2,6-dihydroxyanthraquinone and 2,6-diaminoanthraquinone as the starting compounds. The films, thus obtained, were characterized by Fourier Transform infrared (FTIR), fast atomic bombardment (FAB+) mass and ultraviolet-visible (UV-Vis) spectroscopies. The surface morphology of these films was analyzed by means of atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was found that the temperature-dependent electric current in all cases showed a semiconductor behavior with conductivities on the order of 10⁻⁶·S cm⁻¹, whereas the highest value corresponded to the thin film based upon the bidentate amine. The Tauc and Cody optical band gap values of thin films were calculated from the absorption coefficients and were found to be around 1.5 eV, with another strong band between 2.3 and 2.43 eV, arising from non-direct transitions. The curvature in the Tauc plot influencing the determination of the optical gap, the Tauc optical gap corresponding to the thicker film is smaller. The dependence of the Cody optical gap on the film thickness was negligible.