Platinum thin films were prepared by chemical vapor deposition based on the oxidative decomposition of ͑methylcyclopentadi-enyl͒trimethylplatinum ͓CH 3 C 5 H 4 Pt͑CH 3 ͒ 3 ͔ as a precursor. The film growth is characterized by slow growth during the initial stage, followed by explosive growth on the initial layer. With increasing oxygen ratio and temperature, the duration of the initial stage is shortened and the growth rate on the initial growth layer is increased. However, an Arrhenius plot gives an activation energy of 0.7 eV regardless of the temperature or the oxygen ratio. Therefore, the rate-determining step of the entire reaction is the oxidative decomposition of the precursor on the growth front. On the other hand, an autocatalysis of platinum enhances the oxygen adsorption, which increases the collision frequency between the oxidizing species adsorbed and the source transferred on the growing surface. That is, the oxygen molecules that adsorbed and eventually saturated on the substrate surface shorten the duration of the initial stage and increase the growth rate, since the oxidative decomposition is enhanced by the autocatalysis of a self-seed platinum layer.High permittivity materials such as tantalum pentoxide (Ta 2 O 5 ) and barium strontium titanate ͓͑Ba, Sr͒TiO 3 ͔ will be applied as capacitor dielectrics in 0.13 m generation dynamic random access memories ͑DRAMs͒. Noble metals that are inert against oxidation processes and oxide dielectrics are used for capacitor electrodes because they form a clean interface without forming any additional low permittivity layer between the dielectrics and electrode. In addition, gigabit capacitors must have a three-dimensional structure in order to enhance the surface area of the dielectrics, and consequently to ensure the capacitance.A solution to the above requirements is a chemical vapor deposition ͑CVD͒ of noble metals, ruthenium and platinum. Moreover, a production-worthy process requires CVD precursors that are liquid at ambient temperature and that have high vapor pressure and chemical stability. Alternatively, the precursor would be diluted with some kind of organic solvent in a liquid transfer technique. Fluorides 1 and carbonyl complexes 2 were developed in the early days of the CVD of noble metals. However, they have the disadvantage of bringing about residual fluorine and carbon contaminants in the film. New precursors of cyclopentadienyl ͑Cp͒ complexes were thus developed to avoid this disadvantage. 3-5 Cp complexes have high vapor pressure and chemical stability, and they are easily decomposed in a reducing atmosphere containing hydrogen gas, resulting in carbon-free films. 6 However, the CVD process of noble electrodes in gigabit devices must involve an oxidative decomposition in order to prevent the dielectrics from being reduced during electrode deposition. Recent studies have reported that the platinum electrode is formed by oxidative decomposition of fluoride precursor 7 and the ruthenium electrode is formed from a solid cyclopentadienyl precur...
This paper provides an overview of two topics. First, it presents a unified approach to various techniques addressing the non-uniqueness of the solution of the inverse gravimetric problem; alternative, simple proofs of some known results are also given. Second, it summarizes in a concise and self-contained way a particular multiscale regularization technique involving scaling functions and wavelets. 0266-5611/08/045019+25$30.00
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