International Journal of

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Micro-channels are made over the Ag+/Na+ ion-exchanged soda-lime glass surface by interaction of an intense Ar+ laser beam and the silver ions inside the glass matrix. The Ar+ laser beam reduces the Ag+ ions inside the matrix. The Ag+ atoms aggregate into silver nano-clusters around the interaction area, inside the glass matrix. Aggregation of the silver atoms and the thermal effects of the interaction, changes the geometrical profile of the glass surface. This phenomenon has been used to produce micro-sized channels over the glass surface. During the interaction the glass has moved under the focused laser beam in two dimensions by resolution of 300 nm via a computer controlled xyz sub-micro-positioner to produce the channel walls. Using this technique, micro-channels of 0.3 μm deep and arbitrary width have been made. The height of the produced wall has been determined by interferometry techniques.

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One of the basic requirements in the fabrication of microfluidic (MF) and optofluidic (OF) chips is a suitable initial mold, which is generally prepared with the help of a photoresist material. In this research, we investigate the SPE-60 photoresist as a quality alternative to the conventional SU-8 photoresist to achieve molds with thicknesses ranging from 25μm to 130μm and address the challenges of mold-making with this photoresist. The conventional photolithography method is used to assess the material's ability in mold making. The results show that SPE-60 molds have vertical edges, clean facets, and edges, complete voids between different components, and demonstrate good pattern transfer from the photomask to the SPE-60 film at various thicknesses. This article also suggests some ways to improve accuracy and reduce edge scattering. As a result, based on the experimental results, SPE-60 can be considered a cost-effective and suitable alternative to SU-8 photoresist in the fabrication of MF and OF molds.