Photo resists based

Photo-resist technology is widely used for imaging processes in such applications in electronics. If it is wished to produce a metallic pattern of connections between many electronic components (resistors, capacitors, integrated circuits, etc.), this can be done by the selective etching of a thin copper plate deposited on an insulating base. The copper layer is protected by a resist which is a polymer, deposited in such a way that it prevents the attack of the metal by an etching solution which will solubilize only the unprotected, exposed copper (Figure 6.8). 

Figure 6.8 Photo-resist technology. A metal substrate (s) deposited on an insulator base (b) is protected by the resist (r). Irradiation of the resist through a mask (m) results in photoinduced polymerization or polymer destruction...

During the early years of the microelectronics industry, the imaging process used to define the layers of patterned conductor, insulator, and semiconductor materials that constitute active devices was accomplished by using contact printing in conjunction with resists based on photo-induced cross-linking to generate differential solubility. The resolution of the processes in... 

It is known that the diazo sensitizer is temperature sensitive and decomposes almost completely on heating above 110°c. for 30 min. The decomposition products in the presence of moisture (in the atmosphere) are nitrogen (N ) and indene acid, a base developer soluble material. On extended heating at higher temperature there is a marked decrease in the dissolution rate of both P(MMA)(see figure 1) and the photo resist (figure 2). 

H.-S. Koo, M. Chen, and P.-C. Pan, LCD-based color filter films fabricated by a pigment-based colorant photo resist inks and printing technology. Thin Solid Films, 515, 896 (2006). 

Vladimirov N, Frechet JMJ, Yamada S et al (1999) Photoresists with reduced environmental impact water-soluble resists based on photo-cross-linking of a sugar-containing polymethacrylate. Macromolecules 32 86-94... 

Fish glue is a similar protein-based glue made from the skins and bones of fish. An exceptionally clear adhesive can be made from fish and was the first adhesive used for photographic emulsions for photo film and photo resist coatings for photoengraving processes. 

Wilkins and coworkers have redesigned both the sensitizer and the matrix resin (78-79). They have tested a variety of o-nitrobenzyl esters of cholic acid as sensitizers. These substances, like the diazoquinones, are insoluble in aqueous base but undergo a photo-reaction that yields base soluble products. The matrix resin chosen for the new sensitizer materials is a copolymer of methyl methacrylate and methacrylic acid that is far more transparent than novolac resins in the DUV. The new resist materials are reported to have useful sensitivity (ca. 00mJ/cm ) and extremely high contrast. The resist formulation is essentially aliphatic in nature and would be expected to be less stable to dry etching environments than the aromatic-based novolac resin materials (24). 

Onium salts have been widely used as an acid generator for photo-, EB, and x-ray resist. In addition, aromatic polymers such as novolak and polyhydroxystyrene have been often used as a base polymer for EB and x-ray resist. The reaction mechanisms in a typical resist system have been investigated by pulse radiolysis [43,52,77-88], SR exposure [79,80,83-85], and product analysis [88]. Figure 6 shows the acid-generation mechanisms induced by ionizing radiation in triphenylsulfonium triflate solution in acetonitrile. The yields of products from electron beam and KrF excimer laser irradiation of 10 mM triphenylsulfonium triflate solution in acetonitrile are shown in Fig. 7 to clarify the... 

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