Growth of electrodeposits

Cachet H, Cortes R, Froment M, Mamin G (1999) Epitaxial growth of electrodeposited cadmium selenide on (111) gallium arsenide. Philos Mag Lett 79/10 837-840 Muthuvel M, Stickney JL (2006) CdTe Electrodeposition on InP(lOO) via Electrochemical Atomic Layer Epitaxy (EC-ALE) Studies Using UHV-EC. Langmuir 22 5504-5508 Streltsov EA, Osipovich NP, Ivashkevich LS, Lyakhov AS (1999) Effect of Cd(ll) on electrodeposition of textured PbSe. Electrochim Acta 44 2645-2652 Beaunier L, Cachet H, Cortes R, Froment M (2000) Electrodeposition of PbSe epitaxial films on (111) InP. Electrochem Commun 2 508-510... 

Damjanovic et al. (13) treated the optical determination of mechanisms of lateral and vertical step propagation. Dickson et al. (12) studied the nucleation and growth of electrodeposited gold on surfaces of silver by means of electron microscopy. 

It is interesting to note that it was concluded in this work that the first few angstroms of deposit form an alloy layer. Another interesting and important conclusion in this work is that the sequence of growth of electrodeposits (at 20°C) is very similar to that of the evaporated deposits (at 250 to 300°C). 

Figure 7.14. Sequence of growth of electrodeposited gold (a) 20 A (b) 25 A (c) 40 A I = 200 /jlA, a = 20 mm. (From Ref. 46, with permission from Taylor Francis.)...

Ikemiya et al. [445] have investigated both the atomic structure and growth of electrodeposited Te films on Au(lOO) and Au(lll) with large lattice misfits. Deposition was performed in sulfuric acid solutions using in situ AFM. On both substrates, bulk-deposited Te films were formed according to the Stranski-Krastanov mechanism. Their atomic structures changed with the increasing film thickness. 

Thus, the sequence of growth of electrodeposited gold by the nucleation-coales-cence mechanism has four stages (1) formation of isolated nuclei and their growth to TDC, (2) coalescence of TDC, (3) formation of linked network, and (4) formation of a continuous deposit. This sequence of growth stages is schematically shown in Figure 7.14. 

Fig. 11.8. Current density as a function of rotation rate during growth of electrodeposited polypyrrole film at 0.550 ( ), 0.600 ( ), 0.650 (T), and 0.700 ( ) V. (Reprinted with permission from D. J. Fermin, M. Mostany, and B. Scharifker, Electronically Conducting Polymers Synthesis and Electrochemical Properties of Polypyrrole, Curr. Topics Electrochem. 2 132-136, 1993.)...

Simultaneously, with the rapid growth of electrodeposition in microelectronics, a new trend based on the electrodeposition of materials, structures, particles, devices, etc., generally called nano-objects, with dimensions below 100 nm commenced. Nano-objects are fundamental for nanoscience investigations and nanotechnology development. A nano-object is of particular interest if it has physical properties that differ from objects that have macroscopic sizes. Quantization of energy, for example, is observed in systems with greatly reduced size, such as atoms, molecules, and nanostructures. 

Atomic force microscopy (AFM) and electrochemical atomic force microscopy (ECAFM) have proven usefiil for the study of nucleation and growth of electrodeposited CP films on A1 alloy [59]. AFM was used to study adhesion between polypyrrole and mild steel [60], whereas electric force microscopy (EFM) has been used to study local variations in the surface potential (work function) of CP films [61]. AFM with a conductive tip permits a nanoscale AC impedance measurement of polymer and electrolyte interfaces, permitting differentiation between highly conductive amorphous regions and less-conductive crystalline regions of the CP film [62]. 

Nichols RJ, Bach CE, Meyer H (1993) The effect of three organic additives on the stmcture and growth of electrodeposited copper an in-sity scaning probe microscopy study. Ber Bunsenges Phys Chem 97 1012-1020... 

Pavlovic MG, Kindlova S, Rousar I (1992) The initiation of dendritic growth of electrodeposited copper on a rotating disc electrode with changing copper concentration and diffusion layer thickness. Electrochim Acta 37 23-27... 

Abyaneh, M.Y. and Tajali Pour, A. (1994) The initial nucleation and growth of electrodeposits... 

Lee, I., Chan, K.Y. and Phillips, D.L (1998) Growth of electrodeposited platinum nanocrystals studied by atomic force microscopy. Applied Surface Science, 136, 321. 

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