Lithographic fabrication

Wilson, N. G., McCreedy, T., On-chip catalysis using a lithographically fabricated glass microreactor - the dehydration of alcohols using sulfated zirconia,... 

Bates et al. reported the construction and characterization of a gold nanoparticle wire assembled using Mg -dependent RNA-RNA interactions for the future assembly of practical nanocircuits [31]. They used magnesium ion-mediated RNA-RNA loop-receptor interactions, in conjunction with 15 nm or 30 nm gold nanoclusters derivatized with DNA to prepare self-assembled nanowires. A wire was deposited between lithographically fabricated nanoelectrodes and exhibited non-linear activated conduction by electron hopping at 150-300 K (Figure 16). 

A method to form metal-SAM-metal nanowires with a diameter < 40 nm was developed by Mallouk and coworkers [51, 76]. The nanowires were produced by electrodeposition of Au or Pd into the nanopores of a polycarbonate membrane. A SAM was formed at the end of the wire and a second metal contact (Au, Ag or Pd) was deposited on top of this. The polycarbonate was subsequently dissolved in dichloromethane, which released a large quantity (1011 cm-2) of nanowires that could be aligned individually between pairs of lithographically fabricated metal electrodes. A schematic illustration of the nanowire molecular junctions is shown in Fig. 10.14. 

Spin-valve and other magnetoresistive devices detect the stray field from a magnetic micro- or nanobead, as illustrated by Fig. 2. Lithographically fabricated microcircuits [93-96] may be used to manipulate the magnetic particles. Detection limits in the 102 nM can be achieved, and detection of single particles is theoretically possible. 

Difficult to fabricate desired electrode dimensions accurately - electrode elevation and recession is much more significant. Lithographically fabricated... 

JL olymers are increasingly being used in a wide variety of applications in electronics and photonics, most of which use polymers in their traditional role as engineering materials (e.g., circuit boards, molded products, wire and cable insulation, encapsulants, and adhesives). In addition, many other unique applications require material properties that only polymers can provide. Examples include resist materials for the lithographic fabrication of integrated circuits (1C) and polymers for optical recording. These types of applications may be considered passive in the sense that the polymer does not play an active role in the operation of the device or circuit. Rather, it serves some other function such as mechanical support, electrical insulation, or in the case of resists, some intermediate function in the fabrication of the device. 

One of the attractive ways to make such model structures is based on lithographic techniques. We devote the next section to two important lithographic fabrication model catalyst methods, namely, electron-beam lithography (EBL) and colloidal lithography (CL). Lithography can be defined as a patterning process whereby an initial pattern is designed as some type of dataset which is subsequently written on the surface of a substrate as an array or ordered... 

Table 4.1. Description of lithographic fabrication methods reported in the literature... 

Fig. 4.6. General lithographic fabrication procedure, applicable to both electron-beam lithography and colloidal lithography...

Here, we describe several approaches to study catalytic surface reactions (primarily CO oxidation) on lithographically fabricated model catalysts at atmospheric pressures, in UHV, and in electrocatalysis. In addition, we discuss reaction-induced restructuring of these lithographically fabricated samples. 

Yang, M.X., Gracias, D.H., Jacobs, P.W., and Somogai, G. (1998). Lithographic fabrication of model systems in heterogeneous catalysis and surface science studies. Langmuir, 14, 1458. 

Armani AM, Vahala KJ (2007) Soft lithographic fabrication of microresonators, Digest of the IEEE LEOS Summer Topical Meetings 133-134... 

In order to address the needs of field sensing of explosives, it is necessary to move away from traditional bulky electrodes and cells (commonly used in research laboratories). The exploitation of advanced microfabrication techniques allows the replacement of conventional ( beaker-type ) electrochemical cells and electrodes with easy-to-use sensor strips. Both thick-film (screen-printing) and thin-film (lithographic) fabrication processes have thus been used for high-volume production of highly reproducible, effective and inexpensive electrochemical sensor strips. Such strips rely on... 

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