Transparent conducting thin films preparation

Jayaraj, M.K Aldrin, A. Manoj, R. Transparent conducting zinc oxide thin film prepared by off-axis rf magnetron sputtering. Bull. Mater. Sci. 2002, 25 (3), 227-230. 

As shown above, thiophene-based polymers can have several different side chains and thus different characteristics. An important polymer for PSC based on thiophene is PEDOT PSS which functions as an ETL as described above. PEDOT PSS was developed in the late 1980s at Bayer AG laboratories to be a soluble conducting polymer which did not have undesirable couplings such as a-P or p p [12]. Without the counterion, the polymer was highly crystalline, insoluble, and brittle, but it formed a transparent oxidized thin film that showed a conductivity of 300 S/cm. To ensure solubility, the polymer was prepared with a counterion, and this also resulted in highly conductive films, which were highly transparent and showed high stability [12, 81]. 

Domingues SH, Salvatierra RV, Oliveira MM, Zarbin AJG (2011) Transparent and conductive thin films of graphene/polyaniline nanocomposites prepared through interfacial polymerization. Chem Commun 47 2592-2594... 

Polyaniline (PANI) can be formed by electrochemical oxidation of aniline in aqueous acid, or by polymerization of aniline using an aqueous solution of ammonium thiosulfate and hydrochloric acid. This polymer is finding increasing use as a "transparent electrode" in semiconducting devices. To improve processibiHty, a large number of substituted polyanilines have been prepared. The sulfonated form of PANI is water soluble, and can be prepared by treatment of PANI with fuming sulfuric acid (31). A variety of other soluble substituted AJ-alkylsulfonic acid self-doped derivatives have been synthesized that possess moderate conductivity and allow facile preparation of spincoated thin films (32). 

Successful electrodeposition of Sb2To3 has been reported for the first time by Leimkiihler et al. [229] who prepared polycrystalline thin films of the material on different transparent conductive oxides, as well as CdTe and Mo, from uncomplexed solutions made by mixing stock solutions of SbCb, Te02, and phthalate buffer (pH 4). The electrochemical process was discussed in detail based on results obtained by cyclic voltammetry on ITO/glass. The bath temperature was found to influence... 

M. Buchanan, J.B. Webb, and D.F. Williams, Preparation of conducting and transparent thin films of tin-doped indium oxide by magnetron sputtering, Appl. Phys. Lett., 37 213-215, 1980. 

ZnO thin films can be prepared by a variety of techniques such as magnetron sputtering, chemical vapor deposition, pulsed-laser deposition, molecular beam epitaxy, spray-pyrolysis, and (electro-)chemical deposition [24,74]. In this book, sputtering (Chap. 5), chemical vapor deposition (Chap. 6), and pulsed-laser deposition (Chap. 7) are described in detail, since these methods lead to the best ZnO films concerning high conductivity and transparency. The first two methods allow also large area depositions making them the industrially most advanced deposition techniques for ZnO. ZnO films easily crystallize, which is different for instance compared with ITO films that can... 

In addition to silicon and metals, a third important element being deposited as thin films is diamond (Celii and Butler, 1991 May, 2000). For many years, diamonds were synthesized by a high pressure/high temperature technique that produced bulk diamonds. More recently, the interest in diamonds has expanded to thin films. Diamond has a slew of properties that make it a desired material in thin-film form hardness, thermal conductivity, optical transparency, chemical resistance, electrical insulation, and susceptibility to doping. Thin film diamond is prepared using chemical vapor deposition, and we examine the process in some detail as a prototypical chemical vapor example. Despite its importance and the intensity of research focused on diamond chemical vapor deposition, there remains uncertainty about the exact mechanism. 

Transparent conducting polymers are of interest [66]. A number of these doped conducting polymers have been prepared as thin conductive films. It was shown that the optical window for doped polyaniline and other polymers can be tuned through control of processing conditions [67]. 

Suspensions of polyacetylene were prepared as burrs or fibers (46) by using a vanadium catalyst. When the solvent was removed, films of polyacetylene were formed with densities greater than that prepared by the Shirakawa method. These suspensions were mixed with various fillers to yield composite materials. Coatings were prepared by similar techniques. Blends of polypyrrole, polyacetylene, and phthalocyanines with thermoplastics were prepared (47) by using the compounding techniques typically used to disperse colorants and stabilizers in conventional thermoplastics. Materials with useful antistatic properties were obtained with conductivities from 10" to 10" S/cm. The blends were transparent and had colors characteristic of the conducting polymer. For example, plaques containing frans-polyacetylene had the characteristic violet color exhibited by thin films of solid trans-polyacetylene. 

Thin networks of SWNT can be prepared as transparent and highly conducting films which, in addition, have very good mechanical properties. They can be prepared in a reproducible way by a rather simple method of fabrication at room temperature that does not require high vacuum conditions or expensive equipment. Moreover, SWNT thin films have no equal in the tunability of their electrical, optical, and mechanical properties. By varying the type of nanotube used or the film preparation procedures, researchers can vary electrical and optical responses by several orders of... 

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