Prussian blue (PB) layers were electrodeposited for the fabrication of Au/PB/Ag stacks to study the resistive switching effect. The PB layers were characterized by different techniques to prove the homogeneity, composition, and structure. Electrical measurements confirmed the bipolar switching behavior with at least 3 orders of magnitude in current and the effect persisting for the 200 cycles tested. The low resistance state follows the ohmic conduction with an activation energy of 0.2 eV.

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The aim of the experiments was the characterization of the first stages of film growth on silicon substrates with scanning tunneling microscopy (STM) and angle-resolved X-ray photoelectron spectroscopy (ARXPS). Thin Ta films were deposited in situ by magnetron sputtering onto Si in the thickness range from less than one monolayer up to 10 nm. The results of the experiments show a formation of tantalum silicide at the interface to the substrate. The local current-voltage characteristics obtained by scanning tunneling spectroscopy (STS) measurements show that the first stages of tantalum silicide growth are characterized by island formation. The in situ STM results are in good agreement with those of the ARXPS investigations. 1 Introduction Nowadays, copper is the material for metallic interconnects for the (ultra) large-scale integration in microelectronic devices. Because the copper diffusion into silicon must be minimized, additional diffusion barriers are necessary in such microelectronic devices using copper as wiring material. Up to now tantalum-based thin films are widely used as such barriers [1, 2] and were investigated with different experimental methods [3][4][5]. As a consequence of decreasing barrier thicknesses the knowledge of the first stages of thin film growth on the substrate is necessary [4]. Our experiments on magnetron sputtered ultra thin tantalum-based films complete the knowledge of the tantalum barrier system by results of scanning tunneling microscopy (STM) in comparison with results of X-ray photoelectron spectroscopy (XPS). This leads to additional information about the interface chemistry and the island-like film growth at the silicon substrate, because of the use of high lateral resolved STM also in its spectroscopic I(U)-mode (STS). In measurements with the constant current mode, STM provides hybrid information consisting of both the sample topography and the chemical states on the surface. The tunneling tip exactly follows the sample topography only if the sample surfaces are chemically homogeneous. The spectroscopic STS method in the scanning tunneling microscope also provides information on the sample's electronic surface state. Therefore it is possible to get local information about different chemical compounds on the surface with high lateral resolution using the measurement of the current voltage characteristics in dependence on local position on the sample. Complementary, XPS can deliver large-area information of element composition and chemical bonds at the surfaces. Investigation of surface chemistry is done with the analysis of peak shifts and/or peak shape changes of the photoelectron peaks. By additional use of the angle-resolved XPS (ARXPS) with appropriate model calculations [6,7] one can also get morphological information (film thickness, island growth) which can be compared with the STM/STS results. In this paper we will discuss the results of investigations of tantalum-based ultra thin layers deposited by reactive DC magnetron sputtering. Because of the high reactivi...

This paper presents a low-cost and high-throughput process for nanoscale imprinting of a novel thermally cross-linkable polymer via laser interference lithography. This technique was applied to produce the highly periodic nanometer structures such as lines and dots. The negative of this master pattern was imprinted in the solvent-cast polymer resist via hot-embossing nanoimprint lithography. Using polydimethylsiloxane stamps, it is possible to replicate the original pattern on the resist. The interference lithography process and the master structures are discussed. Lines and dots are hot-embossed applying different holding pressures, achieving a period of 630 nm