Laser micro machining

Micro Structured Fuel Processors for Energf Generation 2.9.2.6 Laser Micro Machining (Ablation)... 

InnovaQuartz (InnovaQuartz, Phoenix, AZ, USA) has successfully manufactured fibre optic tips, using CO2 laser micro machining (Figure 3C). Melting and compressing the fibres eliminates the dead space between them. An increase of power density and almost complete overlap between illumination and collection areas has been reported. However, this technique is limited to fibre bundles with a few fibres only. 

Mannion, R, Magee, J., Coyne, E., O Connor, G., Glynn, T, 2004. The effect of damage accumulation behaviour on ablation thresholds and damage morphology in ultrafast laser micro-machining of common metals in air. Appl. Surf. Sci. 233, 275. 

W. Pfleging, W. Bemauer, T. Hanemann, M. Torge, Rapid fabrication of microcomponents - UV-laser assisted prototyping, laser micro-machining of mold inserts and replication via photomolding, Microsystem Technologies, 9, 67-74 (2002). 

One of the earliest efforts of qualitative measurement of a protein (human serum albumin) in a microchip-based device was based on bead agglutination in a microchamber (approximately lOjaL). Subsequently, several quantitative immunoassays have been performed using microchip electrophoretic systems that permit separation and quantitation of free- and bound-labeled antigens in competitive assays (see Chapter 5). Most are carried out in channels micro-machined into fused silica substrates. Early work on quantitative assays achieved measurement of cortisol in serum.The assay used cortisol labeled with fluorescein and an argon laser detector at 488 nm and required only 80 pL of a 40x dilution of serum as the sample. Other capillary electrophoresis-based assays for a variety of antibodies have also been developed that include immunoglobulins (IgG, IgA, and IgM), antibovine serum albumin, and antiestradiol. ... 

A third way to build up pFCs based on MEMS-polymers such as poly-dimethylsiloxane (PDMS) or polymethyl methacrylate (PMMA) or PCB-materials such as polyimid (PI) or FR4. These polymers can be micro-machined by molding or by laser ablation. Shah et al. [22,23] have developed a complete PEMFC system consisting of a PDMS substrate with micro-flow channels upon which the MEA was vertically stacked. PDMS micro-reactors were fabricated by employing micro-molding with a dry etched silicon master. The PDMS spin coated on micro-machined Si was then cured and peeled off from the master. The MEA employed consisted in a Nafion - 12 membrane where they have sputtered Pt through a Mylar mask. Despite an interesting method, this FC gave poor results, a power density of 0.8 mW cm was achieved. 

Compared to other micromachining processes such as micro-EDM, micro-USM (Ultrasonic machining), micro-LBM (laser beam machining), and tool-based micromachining, the initial setup as well as mnning cost of EMM is lesser. 

A more recent study of droplet ejection from small micro-machined nozzles is provided in Meacham et al. [6]. The acoustic droplet ejection method has found applications in photoresist deposition and matrix-assisted laser desorption ionization (MALDI) analysis [3], among others. 

Ostendorf A., Bauer, T, Korte, F., Howorth, J., Momma, C., Rizvi, N., Saviot, F and Salin, F. (2002) Development of an industrial femtosecondlaser micro-machining system, in Commercial and Biomedical Applications of Ultrafast and Free-Electron Lasers, (eds G.S. Edwards, J. Neev, A. Ostendorf, J.C. Sutherland), Proc. SPIE, 4633, 128-135. 

The oldest laser structuring machine from the LPKF company for LDS is the Micro-LineSD 160i as a single-head laser system complete with rotary indexing table for series production. [103]... 

The micro devices were fabricated from a polyethylene terephthalate (PET) substrate using 193 nm ArF excimer laser ablation [59], Microstructures produced in this way were thermally sealed by a lamination machine. 

Goranovic, G., Klank, H., Westergaard, C., Geschke, O., Telleman, P., Kutter, J.R, Characterization of flow in laser-machined polymeric microchannels. Micro Total Analysis Systems, Proceedings 5th p7AS Symposium, Monterey, CA, Oct. 21-25,... 

Information Technologies of Belarusian State University of Informatics and Radioelectronics, is shown on Fig. 1. It consists of personal computer (1) with specialized software, laser system (4), which includes optic units (5)-(8), laser controller (3), coordinate system (10) with processing object (9), and controller of coordinate system (11). This laser machine was successfully used to form dotty 2D and 3D micro-objects with a pulse laser. Topological possibilities of machines of such type in full measme depend on the used laser, as well as on the software, which includes a set of algorithms for eoordinated control of laser and coordinate system. 

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