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The high- k dielectric material (Ba,Sr)TiO 3 has been intensively investigated for possible applications in dynamic random access memory circuits. During the BST deposition process in O 2 ambient, typically at 650°C, the diffusion of oxygen through the bottom electrode into the poly Si plug must be prevented. Amorphous TaSiN films are excellent candidates as oxygen barrier layers. Ba 0.5 Sr 0.5 TiO 3 (BST) films with thickness of 100 nm were deposited on the electrode structure SiO 2 /TaSiN/Pt. The sol–gel method was used to grow the BST films. The barrier effect for oxygen diffusion is studied in TaSiN layers with thickness of 50 nm, which were deposited by a reactive sputter process. X-ray photoemission spectroscopy results confirm that this amorphous material is a suitable barrier against oxygen diffusion at 650°C. The BST films, deposited at 650°C and post-annealed at 650°C show a dielectric constant of 100 at 100 kHz and a dissipation factor of less than 5%.

Die direkte Analyse elektrisch nichtleitender Materialien mit Hochfrequenzanregung in der Glow Discharge Optical Emission Spectroscopy (GD-OES) eroffnete eine Vielzahl neuer analytischer Einsatzgebiete in der Elementanalyse von Bulk- und Schichtwerkstoffen.

We propose a reaction model for the synthesis of YBa2Cu4O8 under normal pressure conditions, which contains 4 partial reaction steps. In a first step bariumnitrate and copperoxide react to Ba2Cu3O5+δ. This substance will be formed for each mixtures Ba:Cu=2∶3...3∶2. The following two partial reaction steps are connected to Ba2Cu3O5+δ, which reacts with Y2O3 and CuO to YBa2Cu4O8 or decomposes to BaCuO2 and CuO. In a last step parts of BaCuO2 reacts with Y2O3 and CuO to YBa2Cu4O8.

Investigations about the synthesis and the dielectric properties of complex lead-perovskites of the formular Pb (B'B”)O3 (B': Mg, Zn, Ni, Fe; B”: Nb) were presented.

In comparison to the Y 1− x Pr x Ba 2 Cu 3 O 7−δ (Y/Pr-123) system the influence of the substitution of Pr for Y on the structural and superconducting properties of the Y 1− x Pr x Ba 2 Cu 4 O 8 (Y/Pr-124) system was investigated. Among the different reaction procedures for the synthesis at ambient oxygen pressure a technique involving the crystallization from the quenched melt was employed for the first time. In analogy to the Y/Pr-123 system the Pr substitution leads to an increase of the unit-cell parameters and to a successive suppression of superconductivity in Y/Pr-124 with a critical Pr concentration x cr of 0.75 which is higher than that of 0.56 for Y/Pr-123. The normal-state behavior of the Y/Pr-124 samples could be described by a Curie-Weiβ law, yielding effective Pr moments of about 2.5μ B that correspond to a Pr valence of 4+. Different from the Y/Pr-123 system, the Curie-Weiβ temperature θ was found to be positive for the superconducting and negative for the normal samples, whereas in Y/Pr-123 θ was always negative.

It was demonstrated that superconducting 124 material can be successfully prepared by using oxide-nitrate- mixtures or nitrate-mixtures with short reaction times at normal oxygen pressure conditions. Small quantities of CuO, BaCuO2 and Y2BaCuO5 could be detected as phase impurities by X-ray diffraction. The best quality samples were prepared using freeze-dryed nitrate solution with Na2CO3 as an accelerator. The amount of impurity phases in these samples was near the detection limit of X-ray diffractometry.

Ceramic films are considered as key functional material in nano and microsystems technology. IKTS has built the experimental basis for the development of functional films using screen printing, CSD, CVD, PVD, RIE and CMP, covering a wide range of chemical composition, film thickness and processing windows. Substrates of interest are those, forming the integration basis of microsystems, like Silicon (Si) wafers and glass ceramics (LTCC). The present paper is going to discuss the availability of various ceramics films for the design, development and fabrication of advanced nano and microsystems.

Pb(Zr,Ti)O3 (PZT) thin films have been reported to show a significant polarization after deposition without any previous poling treatment which is referred to as self-polarization. This effect has also been found in the here derived PZT thin films using a sol-gel method. The aim of this experimental work was to study the influence of Ti/Pt bottom electrodes on the texture and polarization of sol-gel PZT films The Pt films showed a complete (111) texture. Ti diffused along Pt grain boundaries during pre-annealing of the Ti/Pt electrode and formed TiO2 elevations on the Pt surface. The TiO2 elevations strongly affected the PZT film texture.