Thin film formation, electroless deposition

Simple electroless techniques have been used for the formation of CdTe layers following an anodic or a cathodic route of deposition. For instance, spontaneous cathodic formation of CdTe was observed on Ti or glass electrodes short circuited with a corroding A1 contact (electron source) in a solution of Cd " " and HTe02 ions [96]. After thermal treatment and subsequent growth of an a-Pb02 layer on them, the as-obtained CdTe thin films were found to exhibit n-type behavior in alkaline polysulfide PEC cells. 

There are four types of fundamental subjects involved in the process represented by Eq. (1.1) (1) metal-solution interface as the locus of the deposition process, (2) kinetics and mechanism of the deposition process, (3) nucleation and growth processes of the metal lattice (M a[tice), and (4) structure and properties of the deposits. The material in this book is arranged according to these four fundamental issues. We start by considering the basic components of an electrochemical cell for deposition in the first three chapters. Chapter 2 treats water and ionic solutions Chapter 3, metal and metal surfaces and Chapter 4, the metal-solution interface. In Chapter 5 we discuss the potential difference across an interface. Chapter 6 contains presentation of the kinetics and mechanisms of electrodeposition. Nucleation and growth of thin films and formation of the bulk phase are treated in Chapter 7. Electroless deposition and deposition by displacement are the subject of Chapters 8 and 9, respectively. Chapter 10 contains discussion on the effects of additives in the deposition and nucleation and growth processes. Simultaneous deposition of two or more metals, alloy deposition, is discussed in Chapter 11. The manner in which... 

Gas phase reduction of the hydrated hexafluoroacetylacetonates of Cu and Ni and of the trifluoroacetylacetonates of Cu" and Rh leads to deposition of thin films of the respective metals. Reduction can be carried out at as low as 250 °C and the diketone byproduct can, in principle, be recycled. The facile reduction by hydrogen or hydrocarbons of Pd(CF3COCHCOCF3)2 and its Lewis base complexes provides thin palladium films useful as catalysts or primers for electroless plating. In this case, reduction is facilitated by complex formation since, in the complexes, palladium has a formal positive charge and thus an increased electron aflSnity. Use instead olF hydrogen sulfide allows chemical vapor deposition of metal sulfides such as CdS. ... 

Nanocrystalline particulate films, which exhibit pronounced quantum size effects in three dimensions, are of great interest due to applications in solar cell (108-112) and sensor (57, 113-115) applications. They exhibit novel properties due to not only the SQE manifested by individual nanoparticles but also the total surface area. Unlike MBE and MOCVD methods used to prepare quantum well electrodes, these electrodes can be prepared by conventional chemical routes described in Section 9.5.2.2. For example, II-VI semiconductor particulate films were prepared by using low concentrations of precursors and by controlling the temperature of the deposition bath. Nodes demonstrated the SQE for CdSe thin films deposited by an electroless method (98). The blue shift in the spectra of CdSe films has been demonstrated to be a function of bath temperature. As described in Section 9.5.2.1, electrodeposition of semiconductors in non-aqueous solvents leads to the formation of size-quantized semiconductor particles. On a single-crystal substrate, electrodeposition methods result in epitaxial growth (116, 117), and danonstrate quantum well properties. 

Plated Copper Technology. The various methods of plating copper to a ceramic all begin with the formation of a conductive film on the surface. This film may be vacuum deposited by thin-fihn methods, screen printed by thick-film processes, or deposited with the aid of a catalyst. A layer of electroless copper may be plated over the conductive surface, followed by a layer of electrolytic copper to increase the thickness. 

Peng KQ, Zhu J (2004) Morphological selection of electroless metal deposits on silicon in aqueous fluoride solution. Electrochim Acta 49 2563-2568 Polisski S, Goller B, Lapkin A et al (2008) Synthesis and catalytic activity of hybrid metal/silicon nanocomposites. Phys Status Solidi RRL 2 132-134 Polisski S, Goller B, Heck SC et al (2011) Formation of metal nanoparticles in silicon nanopores plasmon resonance studies. Appl Phys Lett 98 011912 Renaux C, Scheuren V, Flandre D (2000) New experiments on the electrodeposition of iron in porous silicon. Microelectron Reliab 40 877-879 Ronkel F, Schultze JW, Arens-Fischer R (1996) Electrical contact to porous silicon by electrodeposition of iron. Thin Sohd Films 276 40—43... 

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