Thin deposition methods

Ultrathin films of CdS ranging in coverage from 25 to 200 ML were grown also by the previous method on Au substrates (of non-specified nature) and were characterized by quantitative Raman resonance [41], It was found that the electronic structure of the films in this coverage regime corresponds to that of bulk CdS. It was concluded also that ECALE does not involve growth by random precipitation of CdS onto the Au surface the thin deposited layers of the material were contiguous. 

After the precursor stock solution is prepared, various techniques can be used to coat the substrate, depending on the solution viscosity, required film thickness and coverage. The most common methods in the semiconductor industry are spin- and dip-coating. Other processes that are used for deposition include spray coating and stamping. A summary of the uses, limitations, and advantages of the various thin film deposition methods is reported in Table 2.2. 

Over the course of the past 20-25 years, hundreds of studies on the fabrication of electronic thin hlms by chemical solution deposition methods have been reported. Because previous review articles have focused on summarizing the results of these investigations, they are not considered in detail here, but rather a more general approach to him formation and subsequent structural... 

Waser, R. Schneller, T. Ehrhart, P. Hoffmann-Eifert, P. 2001. Chemical deposition methods for ferroelectric thin films. Ferro. 259(l-4) 205-214. 

Tolstoi, V. P. 1993. Synthesis of thin-layer structures by the ionic layer deposition method. Russ. Chem. Rev. 62 237-242. 

Jimenez-Gonzalez, A. Nair, P. K. 1995. Photosensitive ZnO thin films prepared by the chemical deposition method SILAR. Semicond. Sci. Technol. 10 1277-1281. 

Lokhande, C. D. Pathan, H. M. Giersig, M. Tributsch, H. 2002. Preparation of Znx(0,S)y thin films using modified chemical bath deposition method. Appl. Surf. Sci. 187 101-107. 

Although the sputter deposition technique can provide a cheap and directly controlled deposition method, the performance of PEM fuel cells with sputtered CLs is still inferior to that of conventional ink-based fuel cells. In addition, other issues arise related to the physical properties of sputtered catalyst layers, such as low lateral electrical conductivity of the thin metallic films [96,108]. Furthermore, the smaller particle size of sputter-deposited Ft can hinder water transport because of the high resistance to water transport in a thick, dense, sputtered Ft layer [108]. Currently, the sputter deposition method is not considered an economically viable alternative for large-scale electrode fabrication [82] and further research is underway to improve methods. 

An alternative method for producing thin deposits consists in avoiding single-step processes by chemisorbing the precursor and then having it decomposed thermally [1]. Such a method, often named atomic layer deposition or gas phase impregnation-deposition, provides very thin deposits due to the presence of a... 

Formation of metal nanoparticles in ultra thin polyelectrolyte systems was carried out using polydiallyldimethyl ammonium chloride (PDADMAC) by the layer-by-layer deposition method. PDADMAC was purchased from Aldrich (Mw = 400 000 - 500 000). The structure of PDADMAC is shown in Fig. 4. 

The main characteristics of the various titanium oxide catalysts used in this chapter are summarized in Table 1. Titanium oxide thin film photocatalysts were prepared using an ionized cluster beam (ICB) deposition method [13-16]. In ICB deposition method, the titanium metal target was heated to 2200 K in a crucible and Ti vapor was introduced into the high vacuum chamber to produce Ti clusters. These clusters then reacted with O2 in die chamber and stoichiometric titanium oxide clusters were formed. Tlie ionized titanium oxide clusters formed by electron beam irradiation were accelerated by a high electric field and bombarded onto the glass substrate to form titanium oxide thin films. 

LAPS was introduced by Sato et al. [155]. The detection of heavy metal ions by thin films of chalcogenide-glass membranes using the pulsed laser deposition method (PLD) was reported by Mourzina et al. [156]. The PLD technique was also introduced to evaporate A1203 as a pH-sensitive material for LAPS devices [157]. The first practical application of the above-described LAPS card was demonstrated by Kloock et al. for a comparative study of Cd-sensitive chalcogenide glasses for ISFETs, LAPS and pISEs (ion-selective electrodes) [158]. 

Three techniques have been described in the literature to prepare combinatorial libraries of fuel cell electrocatalysts solution-based methods [8, 10-14], electrodeposition methods [15-17] and thin film, vacuum deposition methods [18-21]. Vacuum deposition methods were chosen herein for electrocatalyst libraries in order to focus on the intrinsic activity of the materials, e.g., for ordered or disordered single-phase, metal alloys. 

Amorphous Silicon An alloy of silica and hydrogen, with a disordered, noncrystalline internal atomic arrangement, that can be deposited in thin layers (a few micrometers in thickness) by a number of deposition methods to produce thin-film photovoltaic cells on glass, metal or plastic substrates. 

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