Two-dimensional molecular clusters of a few tens nanometer size were found in spread monolayers of a series of partially fluorinated long-chain acids. Atomic force microscopy images have revealed that the size of the clusters is sharply monodisperse. The size changes systematically with changing structure of the hydrophobic chain of the amphiphiles. The smallest cluster has a circular shape of 17 nm diameter. One cluster is composed of about 700 film molecules. These clusters gather to form macroscopic domains of millimeter size without compression. A formation mechanism of these molecular clusters is discussed. Clusters are formed during the spreading process due to the instability of the film materials at the spreading process. It was made clear that cluster formation during the spreading is rather general for amphiphiles under the conditions where condensed monolayers are formed.

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Distribution of the electrical properties of indium-tin oxide (ITO) film prepared by both a planar-magnetron sputtering system (PMSS) and a facing-targets sputtering system (FTSS) at room temperature were investigated. It was found that the outstanding non-uniformities of the electrical properties in noncrystalline ITO films are mainly due to the variation of the oxygen stoichiometry dependent on film positions on substrate surfaces. Furthermore, ITO film with uniform distribution of electrical properties was obtainable using FTSS.