Micro-patterning

It should be understood that even for micro surface features the potential is uniform and the ohmic resistance through the bath to peaks and valleys is about the same. Also, electrode potential against SCE will be uniform. What is different is that over micro patterns the boundary of the diffusion layer does not quite follow the pattern contour (Fig. 12.3). Rather, it thus lies farther from depth or vias than from bump peaks. The effective thickness, 8N, of the diffusion layer shows greater variations. This variation of 8N over a micro profile therefore produces a variation in the amount of concentration polarization locally. Since the potential is virtually uniform, differences in the local rate of metal deposition result if it is controlled by the diffusion rate of either the depositing ions or the inhibiting addition (leveling) agents. 

Fink J, Thery M, Azioune A et al (2007) Comparative study and improvement of current cell micro-patterning techniques. Lab on a Chip 7(6) 672-680... 

Bouaidat S, Berendsen C, Thomsen P et al (2004) Micro patterning of cell and protein nonadhesive plasma polymerized coatings for biochip applications. Lab on a Chip 4(6) 632-637... 

Ahmed WW, Wolfram T, Goldyn AM et al (2010) Myoblast morphology and organization on biochemically micro-patterned hydrogel coatings under cyclic mechanical strain. Biomaterials 31 250-258... 

Gauvreau V, Laroche G (2005) Micro pattern printing of adhesion, spreading, and migration peptides on poly(tetrafluoroethylene) films to promote endothelialization. Bioconjug Chem 16(5) 1088-1097... 

Montagne K, Komori K, Yang F et al (2009) A micro patterned cell array with an integrated oxygen-sensitive fluorescent membrane. Photochem Photobiol Sci 8(11) 1529-1533... 

Hahn, R.,Wagner, S., Schmitz, A., Reichl, H. (2004). Development of a planar micro fuel cell with thin film and micro patterning technologies. /. Power Sources 131, 73-78. 

Britland S, Perez-Amaud E, Clark P, McGinn B, Connolly P, Moores G. Micro-patterning proteins and synthetic peptides on solid supports A novel application for microelectronics fabrication technology. Biotechnol Prog 1992 8 155-60. 

De Silva MN, Desai R, Odde DJ. Micro-patterning of animal cells on PDMS substrates in the presence of serum without use of adhesion inhibitors. Biomed Microdevices 2004 6 219-22. 

Hosokawa, Y., Kaji, T., Shukunami, C., Hiraki, Y., Kotani, E., Mori, H. and Masuhara, H. (2007) Nondestructive micro-patterning of proteinous occlusion bodies in water by femtosecond laser-induced mechanical force. Biomed. Microdevices, 9, 105-111. 

Fortunately, it is found possible also to apply the methods of microelectronics to, for example, mechanics, optics, fluidics, and, finally, chemistiy or biochemistiy. Systems may thus be designed with extreme functional density and powered at costs which do decrease by orders of magnitude year by year. The recognition of this prospect was the main reason why methods of manufacturing micro-patterns were devised, and these micro-patterns were combined in micro-systems. Thus, one may state that microelectronics should be considered as the source from wliich micro-systems engineering sprung. From the start it was clear that, even though a... 

In the course of this development, avenues for micro-pattern production based on microelectronics opened, perhaps not in detail, but in die basic underlying concepts. 

The photo-induced area-selective reactions occuring on semiconductor electrodes can be utilized as a new method of the micro-patterning of polymer materials. We have shov/n here that both the conductive and the insulating polymers are deposited area-selectively on the electrodes employed, giving examples of... 

V. Sivagnanam, B. Song, C. Vandevyver, and M.A.M. Gijs On-chip immunoassay using electrostatic assembly of streptavidin-coated bead micro-patterns. Andytical Chemistiy 81, 6509-6515 (2009)... 

The most commonly practiced means for fabricating micro-patterned hydrogels is based on in-situ photo-polymerization and photo cross-linking using UV light in a liquid phase. A drawback of this method is that the prepolymer or polymer solution has to be brought into the irradiation set-up. An alternative approach is to cross-link a prefabricated dry film of the sensitive polymer. 

R. C. Hayward, D. A. Saville and I. A. Aksay, Electrophoretic assembly of colloidal crystals with optically tunable micro-patterns. Nature, 404 (2000), 56-59. 

On one side the development is based on thin film and micro-patterning technologies. Wafer level and foil processes used to produce high density interconnect electronic modules, and wafer level packaging was adapted to micro fuel cell development to achieve the required miniaturisation and cost reduction. By using reactive ion etching, high aspect ratio capillary structures of the anode and cathode side flow fields were achieved. 

Nevertheless, the total performance of the micro fuel cells is in the same range of current density compared to the best conventional cells and is at the same time highly miniaturised and capable for mass production which is a clear success of our micro-patterning approach. 

Matsunaga D, Tamaki T, Akiyama H, Ichimura K. 2002. Photofabrication of micro patterned polarizing elements for stereoscopic displays. Adv Mater 14 1477 1480. 

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