Transparent conducting oxides

Figure 4 shows the basic constmetion of the devices used in different appHcations, involving the deposition of multilayers of i -SiH of intrinsic (/), doped ), and closely aUied films, such as amorphous siHcon nitride, SiN, and transparent conducting oxide (TCO). As in crystalline... 

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... 

For review of transparent conductive oxides, refer to the special issue of MRS Bull. 25(8), 2000 and the Proceedings of the MRS Workshop on Transparent Conducting Oxides (Denver, CO, June 19-20, 2000). 

Very recently, even transparent conducting oxides (TCOs), such as indium-tin-oxide (ITO), have been prepared using suitable KLE templates.59 As one potential application, such porous TCOs (ZnO, etc.) are interesting for use in dye-sensitized solar cells. In general, such porous electrodes cover a variety of potential electro-optical applications, because they are both conducting and transparent. 

Figure 9.7. Illustration of the usage of mesoporous films of transparent conducting oxides for novel types of solar cells. The dark gray areas correspond to ITO, the brighter ones to an oxide deposited onto the TCO matrix. The sphere symbolizes a dye. For instance, such films can be used as porous electrodes to include dyes and to deposit semiconductors such as ZnO. 

Other materials such as gold (< = 4.9 eV), aluminum (< = 4.2 eV), indium-doped zinc oxide, magnesium indium oxide, nickel tungsten oxide, or other transparent conductive oxide materials, have been studied as anodes in OLEDs. Furthermore, the WF of ITO can be varied by surface treatments such as application of a very thin layer of Au, Pt, Pd, or C, acid or base treatments, self-assembly of active surface molecules, or plasma treatment. 

Transparent composites, sol-gel technology in, 23 81 Transparent conducting oxides (TCOs), 22 135, 12 610-611 Transparent fused silica, 22 401 Transparent lotus effect thin films, 22 121 Transparent nonmetals... 

Substrates DME = dropping mercury electrode FTO = fluorine-doped tin oxide G = graphite GC = glassy carbon GrC = graphic carbon ITO = indium tin oxide-coated glass SC = single crystals SS = stainless steel TCO = transparent conducting oxide VC = vitrious carbon. Miscellaneous ECALE = electrochemical atomic layer epitaxy ED = electrodeposition ML = monolayer RT = room temperature SMD = sequential monolayer deposition V = vacuum. 

In Table 1.1 a number of properties of zinc oxide are summarized in comparison to other transparent conducting oxides and to silicon. 

Fig. 1.19. Transparent conducting oxide electrodes in different types of thin film solar cells. TCO contacts are given at the bottom of each structure. The bottom most row indicates the doping type of the semiconductor, which is in contact to the TCO...

Recently, field-effect transistors based on zinc oxide were reported [173,174], opening the opportunity to design microelectronic devices that are transparent and/or work at high temperatures [175]. More details on thin film transistors employing transparent conducting oxides are given in Chap. 2. 

This process is obviously a natural scattering process in polycrystalline materials, since polycrystalline films exhibit a high concentration of crystallographic defects, especially dislocations [133,134]. However, this process is rarely used to explain experimental data of carrier transport in polycrystalline semiconductors and especially transparent conducting oxides [88], which is mainly due to the fact that in most works on transport properties of polycrystalline films the density of defects was not determined. Podor [135] investigated bended n-type Ge crystals with a dislocation density around 107 cm 2... 

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