A novel technique for the fabrication of micro-structures on Ni-alloy by DPSS laser ablation was studied
and reported in this paper. Using a q-switched Nd:YVO4 laser, a Ni alloy was micro-machined without lithography-based technologies. The effects of various process parameters such as working power, laser frequency, scan speed and number of scan were examined during laser processing. The removal of debris during ablation was also studied, and performed under vacuum conditions. The obtained prototype was tested by optical microscopy, Scanning Electron Microscopy, EDX and 3D microprofilometer. The obtained structured nickel alloy can be used as master for imprinting on glass substrates for lab-on-chip applications.
Micro-channels were fabricated in sodalime glass through imprinting, and then joined to a glass slab by thermal assisted
direct bonding (TADB). These techniques are simple and low cost, suitable for mass production of micro-fluidic devices.
The joined samples were characterized before and after TADB by optical microscopy, profilometer, SEM, shear strength
test and Vickers hardness test. The integrity of channels is maintained also after the TADB. The interface between the
two glass slabs was found to be without impurities, bubbles and cracks. The bonding strength was also measured to be
TeO2-ZnF2-PbO-Nb2O5 based fluorotellurite glasses were synthesized and studied for the first time for laser
applications. The property characterizations including XRD and thermal analysis as well as optical properties
measurement were performed. It is demonstrated that this fluorotellurite system has good glass formation ability; and
increasing the ZnF2 concentration to 30 mol% can significantly increase the thermal stability of the glass. Adding ZnF2
also reduced remarkably the hydroxyl (OH) concentration of the glass resulting in lower optical absorption in the
infrared region, which is crucial for infrared laser applications. In addition, the glass absorption cut-off edge near 400 nm
blue-shifted with increasing ZnF2 addition.
New germanosilicate glasses with high photosensitivity were fabricated and studied. Addition of sodium produced an increase of 6-fold Ge ions and the appearance of a UV absorption band at 285 nm in the as cast glasses. Laser exposure produced bleaching of such band, when present. Further studies are needed to correlate the two phenomena and find out the best composition in terms of photosensitivity. A new tin sodium silicate glass was also fabricated: glass fibers were produced and high temperature stable gratings were obtained by irradiation with a UV laser.
Er/Yb-doped multicomponent SiO2-GeO2-B2O3-Na2O glasses with different GeO2, B2O3 and Na2O contents were studied. The effect of glass component on the properties of Er ions in terms of absorption cross-section, fluorescence lifetime τm and quantum efficiency was investigated with the aim of obtaining efficient active waveguide.