The induced co-deposition mechanism in one-step electrodeposition of Cu 2Ϫx Se and CuInSe 2 thin films was investigated. Cu 2Ϫx Se and CuInSe 2 thin films were deposited potentiostatically on Mo substrates by a one-step process from an acidic electrolyte containing SCN Ϫ ions as complexing agents. The films were examined by scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, and ion beam analysis methods. Good control of stoichiometry was achieved over a wide potential range, thus indicating that the film composition may indeed be controlled by the induced co-deposition mechanism. The effects of the thiocyanate ions on the reduction potentials of Cu ϩ , In 3ϩ , and Se 4ϩ ions were examined by cyclic voltammetry. In order to improve their crystallinity, the CuInSe 2 films were annealed under a N 2 atmosphere after deposition.

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For the first time an element other than a metal was deposited by atomic layer deposition (ALD). Pure and conformal thin films of elemental antimony were prepared by ALD using SbCl3 and (Et3Si)3Sb as precursors. In situ reaction mechanism studies showed that the dehalosilylation reactions involved are very efficient in eliminating the ligands from the growing surface enabling the use of low growth temperatures down to 95 °C. Various antimony compounds, such as GeSb, Sb2Te, GaSb, and AlSb, can also be deposited by reacting (Et3Si)3Sb with other metal halides or mixing Sb growth cycles with other ALD processes. The new antimony ALD process is a major step in the realization of non-volatile phase change random access memories (PCRAM) and ALD of III−V compounds.

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Uniform coating of macroscopic porous substrates is a great challenge with a huge potential impact. In principle, atomic layer deposition (ALD) is an ideal method of coating porous substrates but it has, so far, suffered significantly from the long processing times needed with high aspect ratio (depth to diameter ratio) structures. This paper is a report of a new ALD reactor design that makes it possible to uniformly coat macroscopic through-porous substrates nearly as quickly as planar surfaces. The improvement gained by this new reactor essentially brings a third macroscopic dimension into ALD processing, and is expected to open up entirely new application areas for coated porous substrates.Coating of substrates that are through-porous is needed in a wide variety of applications, such as 3D integrated circuits, printed circuit boards, electrodes for electrochemical applications like fuel cells and gas generators, 3D capacitors, X-ray optics based on microchannel plates, scaffolds for hard-and soft-tissue engineering and replacement, and heterogeneous catalysts and filters of various kinds. However, in only some of these applications can the coating be performed satisfactorily, and even in these cases there are certain minimum dimensions the pores must have. As the aspect ratio increases most of the coating methods will face problems in terms of film uniformity inside the pores. Methods such as thermal oxidation and anodization do not suffer from this limitation but are very limited in material selection, for example, with anodization only an oxide of the substrate material can be formed on the surface.Among the various thin-film deposition techniques, ALD [1][2][3] offers the greatest potential in coating high aspect ratio structures, including macroscopically porous substrates. The superior conformality of ALD is a consequence of its unique self-limiting growth process where alternately supplied precursor vapors react with each other on the surface in a saturating manner. The self-limiting growth mechanism ensures not only excellent conformality, but also large area uniformity, as well as simple and accurate control of film thickness and composition down to an atomic layer level. A wide variety of thin film materials can be produced using ALD, [1] giving it a considerable advantage over the few other methods, such as oxidation and anodization, that can be used in coating very high aspect ratio structures. When porous substrates are to be coated by ALD, the precursors need to diffuse into and out of the pores during each precursor pulse, i.e., twice during one ALD cycle and hundreds, or even thousands, of times when a film with a thickness in the range of 100 nm is needed. In typical ALD reactors the precursors flow over the surface of the substrate, carried by an inert carrier gas ( Fig. 1 top and middle), and the transportation of the precursor molecules