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We have studied by transmission electron microscopy the microstructural effects induced by pulsed laser annealing in comparison with thermal treatments of RF plasma hydrogenated Si wafers aiming for further application in the smart-cut procedure. While thermal annealing mainly produces a slight decrease of the density of plasma-induced planar defects and an increase of the size and number of plasma-induced nanocavities in the Si matrix, pulsed laser annealing of RF plasma hydrogenated Si wafers with a 355 nm wavelength radiation results in both the healing of defects adjacent to the wafer surface and the formation of a well defined layer of nanometric cavities at a depth of 25-50 nm. In this way, a controlled fracture of single crystal layers of Si thinner than 50 nm is favored. [ABSTRACT FROM AUTHOR]

In this study we describe a simple method to fabricate microarrays of polystyrene microbeads (PS-μbeads) on Thermanox coverslip surfaces using laser induced forward transfer (LIFT). A triazene polymer layer which acts as a dynamic release layer and propels the closely packed microspheres on the receiving substrate was used for this approach. The deposited features were characterized by optical microscopy, scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. Ultrasonication was used to test the adherence of the transferred beads. In addition, the laser ejection of the PS-μbead pixels was investigated by time resolved shadowgraphy. It was found that stable PS-μbeads micropatterns without any specific immobilization process could be realized by LIFT. These results highlight the increasing role of LIFT in the development of biomaterials, drug delivery, and tissue engineering. [ABSTRACT FROM AUTHOR]

Examines an evidence of refractive index change by thallium (TI) indiffusion into LiNbO[sub3] substrate as a result of multipulse free-running ruby laser irradiation. Analysis of thermal behavior of the structures under the action of the free-running ruby laser irradiation; Description of the visual and optical microscopy evidence; Impact of TI implantation on the ordinary refractive index value.

Presents a study that reported data concerning the plasma initiation in front of metallic and dielectric surfaces under the action of pulsed carbon dioxide laser radiation. Time characteristics of the breakdown initiation processes; Dependence of the processes on the irradiation spot dimension; Factors for the delay between the breakdown coming out and the beginning of the laser pulse.

We demonstrate the use of matrix-assisted pulsed laser evaporation technique for incorporating drugs (indomethacin) within thin films of polymer blends, to be used as biodegradable implants that deliver drugs in a controlled manner. For irradiation at fluences up to 1 J/cm2, the films show excellent surface morphology and the chemical structure of all constituent polymers within the blend is well preserved. The optical characteristics of the films are assessed by spectroscopic ellipsometry. The presence of the drug within the polymeric films is confirmed by its specific absorption at 319 nm. [ABSTRACT FROM AUTHOR]