Vapour Deposition of Gold

Complexes of this type may contain a variety of orgaiuc residues R, such as alkyl, vinyl, alkynyl or aryl. The neutral donor group L is most commonly a tertiary phosphine or an isocyanide ligand, and polynuclear complexes with bridging polyfunctional donor ligands are also known . From a practical point of view, the series of organogold(I) and isocyanide complexes is of particular interest since some of its members hold promise as precursors for the chemical vapour deposition of gold films. A selection of these and other compounds of the type [RAuL] is presented in Tables 1-3. 

Dimethyl(acetylacetonato)gold(lll), [AuMe2(acac)] (4), is of great interest as a precursor for the chemical vapour deposition of gold. ... 

Banno et al. studied the enantioselective crystal growth of leucine on self assembled monolayers with covalently attached D or L-leucine molecules (Banno et at, 2004). The monolayers were formed in the following way gold substrates were prepared by vapour deposition of gold on quartz crystals. The substrates were flame annealed and subsequently immersed in 2 mM ethanolic solutions of 11-mercaptoundecanoic acid (MAU). Leucine was then covalently attached to the MAU monolayer. The crystals on the SAM were grown by immersing the substrates in saturated solutions of D, L or DL-leudne. 

Table 4.7 Characteristics of gold on various supports prepared by chemical vapour deposition of Me2Au(acac).97...

Surface-barrier detectors are prepared from n-type Si. On one side the surface is etched and exposed to air to produce an oxide layer, and a thin gold layer is deposited for electrical contact. By this procedure a p-layer is obtained with a thickness of < 1 pm. Another method of preparation of surface-barrier detectors is the vapour deposition of A1 on Si. The maximum thickness of the depicted layer is of the order of 1 mm. Surface-barrier detectors are mainly used for charged-particle spectrometry and for a and f spectrometry. Optimal energy resolution for and / radiation is obtained with thin detectors of small surface area. For instance, at surface areas of about 1 to 4cm, the energy resolution for a and f radiation is about 10 to 30keV. 

Another plasmon resonance approach for detection of mercury vapour is based on localized plasmon resonance in gold nanoparticles deposited on transparent support (Fig. 12.4, right). Changes of the refractive index of gold nanoparticles due to adsorption of mercury should lead to modification of the gold plasmon band of optical adsorption spectra. This approach has been applied successfully for investigation of interaction of biomolecules however, to our knowledge there is still no report on its applications for detection of mercury vapour. 

Thin films of thickness typically 10 nm are readily formed in a vacuum chamber by evaporation, sputtering , or chemical vapour deposition (CVD). Many metals and metal alloys, e.g. aluminium, silver, gold and Ni-Cr, can be... 

Figure 7.1 Schematic procedure for pCP of nanoparticies followed by selective gold deposition either by electroless deposition (ELD) or by chemical vapour deposition (CVD).

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