Polymer planar metallization with

A likely candidate for the role of interlevel dielectric is polyimide on the basis of its relative purity and planarizing spin-on application. In fact, planarizing metal with polymer or so-called PMP technology was pioneered by Hitachi to develop two metal level transistors. More recently, several other... 

The sensor covalently joined a bithiophene unit with a crown ether macrocycle as the monomeric unit for polymerization (Scheme 1). The spatial distribution of oxygen coordination sites around a metal ion causes planarization of the backbone in the bithiophene, eliciting a red-shift upon metal coordination. They expanded upon this bithiophene structure by replacing the crown ether macrocycle with a calixarene-based ion receptor, and worked with both a monomeric model and a polymeric version to compare ion-binding specificity and behavior [13]. The monomer exhibited less specificity for Na+ than the polymer. However, with the gradual addition of Na+, the monomer underwent a steady blue shift in fluorescence emission whereas the polymer appeared to reach a critical concentration where the spectra rapidly transitioned to a shorter wavelength. Scheme 2 illustrates the proposed explanation for blue shift with increasing ion concentration. 

Scheme 6 represents coordinate polymers. A low-molecular-weight compound with multidentate groups on both ends of the molecule grows into a linear polymer with metal ions, and the polymer chain is composed of coordinate bonds. The parquetlike polymer complexes, poly(metal-phthalocyanine) and poly(metal-tetracyano-ethylene), are classified into Scheme 7. They are formed by inserting metal ions into planar-network polymers or by causing a low-molecular-weight ligand derivative to react with a metal salt and a condensation reagent.

The combination of metal cyanide anions with di- and triorganotin moieties gives heterobimetallic coordination polymers of the general formula [(RmSn )j M(CN) 3,] that have been explored very systematically. So far, mainly complexes with square-planar (Ni), tetrahedral (Cu), octahedral (Fe, Co, Ru, Os), " and square antiprismatic (Mo, [M(CN) ] coordination environments have been... 

It is straightforward to visualize how transition metals with either Lewis acid or redox activity might be incorporated into coordination polymers. Indeed, as described earlier [91], the first case of a porous coordination polymer with catalytic activity was recently reported. Square planar metals would be particularly amenable to forming square grid polymers with claylike intercalation capabilities. Thus far, there has been no published work in this area. 

Transition metal square-planar complexes generally contain eight d electrons and are almost always diamagnetic. This includes complexes of Pt, Pd % Au, Rh, and Ir. While such complexes can imdergo other reactions such as redox processes, we shall focus on substitution reactions. Good reviews of square-planar substitution reactions are available. The following is a summary of some of these substitution processes, wifli emphasis on those involved with polymer formation. These substitution reactions are the most widely studied of the transition metal square-planar complex reactions. 

Jung W, Jang A, Bishop P, Ahn CH (2011) A polymer lab chip sensor with microfabricated planar silver electrode for continuous and on-site heavy metal measurement. Sens Actuat B 155 145-153... 

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