dc sputtered indium-tin-oxide films have been excimer laser irradiated at subablation threshold fluences (<510 mJ/cm2). Optical characterization of irradiated products has been performed aiming at resolving the finer structure appearing in the IR–visible absorption spectra, as a function of laser fluence, and assigning such features to specific electronic defects which are produced upon irradiation. Four individual Gaussian-like contributions to absorption spectra are identified at 0.7, 1.0, 1.6, and 2.6 eV, the intensity of which is observed to vary with fluence. Being absent in the original films and emerging in optical spectra at fluences exceeding 300 mJ/cm2, the 2.6 eV contribution is most characteristic to excimer laser processing and is responsible for the darkening of the film. Thermal model calculations reveal that such defects are produced only upon melting and fast resolidification of the film. The evolution of the chemistry actually taking place in the film upon irradiation is followed by x-ray photoelectron spectroscopic analysis. A chemical approach to the production of such defects is proposed in which oxygen displacement in the atomic matrix leads to the formation of neutral ternary complexes of the type SnIn2O4.

The glass transition of pure and diluted honey and the glass transition of the maximally freeze-concentrated solution of honey were investigated by differential scanning calorimetry (DSC). The glass transition temperature, of the pure honey samples accepted as unadulterated varied between -42 and -51 degrees C. Dilution of honey to 90 wt % honey content resulted in a shift of the glass transition temperature by -13 to -20 degrees C. The concentration of the maximally freeze-concentrated honey solutions, as expressed in terms of honey content is approximately 102-103%, i.e., slightly more concentrated in sugars than honey itself. The application of DSC measurements of and in characterization of honey may be considered, but requires systematic study on a number of honeys.

A simple single-step technique for surface patterning is presented. It is shown that well-adhering micrometer-sized patterns of 100% coverage preserving the shape and dimensions of the ablated area can be deposited by ablating and transferring tungsten thin films in the form of single solid pieces using single pulses of peak power up to 100 mW and 100 μs–1 ms duration from a diode-pumped YAG laser.

No abstract

Laser-induced transfer of thin films is a simple single-step technique for surface patterning. In this paper the optimization principles and processes are outlined which led to successful application of the long-pulse laser transfer technique. The critical analysis of experiments on ns-pulse laser transfer of thin films of a variety of metals and the optimization study of the long-pulse laser transfer technique suggests that efficient deposition of high-quality patterns of micrometer dimensions can only be expected when using long laser pulses which not only produce ablation of the thin film pattern in solid phase but also maintain sufficient temperature during transfer and even on landing, to ensure film adherence. In order to identify and understand the different time-dependent processes determining the laser transfer, studies using optical and electron microscopy and static and time-resolved optical measurements were performed.