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ZrO2 films with a sub-10-nm thickness and a roughness of about 0.2 nm have been prepared on Si(001) by a sol-gel process based on zirconium-(IV)-n-propoxide. The topography of the obtained samples has been controlled by atomic force microscopy. Chemical composition and interface reactions of the deposited films have been studied by x-ray photoemission spectroscopy and Auger electron spectroscopy. The ZrO2 films are stable against heating (up to 700 °C) in a moderate oxygen atmosphere (2×10-5 mbar oxygen partial pressure). Minor changes in the surface composition occur after rapid annealing up to 1000 °C. [ABSTRACT FROM AUTHOR]

Optical second-harmonic generation (SHG) studies of Si/SiO2 interfaces by resonant two-photon excitation of Si interband transitions are reviewed. Three different types of interband resonances at Si interfaces are identified in SHG spectra: (i) E1 and E2 critical-point bulk interband transitions in the space-charge region of charged Si interfaces, (ii) E1- and E2-type transitions associated with Si atoms at the interface in bulk-like tetrahedral coordination, and (iii) transitions related to Si interface atoms with bonding properties specific of the atomic structure of the interface. The effects of the polarity of space-charge fields on SHG spectra of Si(100)/SiO2 interfaces are also discussed. [ABSTRACT FROM AUTHOR]

Embedded conventional fibre Bragg grating (FBG) sensors with acrylate coating have been chosen for monitoring novel textile-reinforced composite materials with a complicated wavy structure as a result of reinforcing textures. Problems of monitoring this type of material occur due to the harsh fabrication technology of the composite and its complicated structure. Embedded fibre sensors are exposed to the influence of transverse and point-wise deformations. To what extent will these effects influence the measurement signal of a sensor? Temperature cycles, tension and vibration tests were carried out to answer this question. Transverse and point-wise deformation and micromechanical indentation tests on non-embedded FBG sensors were carried out to clarify the reliability of recorded signals. [ABSTRACT FROM AUTHOR]

Examines the simplification of the inter-layer coupling calculations for secondary interconnect structures. Coupling of adjacent signal lines on individual layers; Coupling of lines on adjacent layers.

Examines the efficiency of lithium borate crystals as optical parametric generator and amplifier of tunable, high-power picosecond pulses. Performance of the pump-to-signal conversion in a device with a wide tuning range; Influence of the pump intensity on the bandwidth of the tunable output; Determination of the duration of signal and idler pulses.

ZrO2 films with a thickness as low as 4 nm and a roughness of about 0.2 nm have been deposited on Si(001) by a sol-gel process. After pyrolysis in air clean and dense ZrO2 films were obtained. To simulate the influence of thermal processes in complementary metal-oxide-semiconductor fabrication on high-k gate oxides, our samples have been subjected to heat treatments up to 1000 °C. The chemical composition of the ZrO2 films and of the interface region has been monitored by Auger electron spectroscopy (AES) and AES depth profiles. No notable chemical changes in the interface region have been detected after heating at 700 °C in 2×10-5 mbar oxygen partial pressure and rapid annealing to 1000 °C. At 700 °C and 10-4 mbar oxygen partial pressure an intermediate interface layer starts to grow by oxidation of the Si substrate. Annealing above 700 °C in UHV leads to the destruction of the sample. Loss of oxygen is accompanied with the formation of islands containing Zr and Si and of holes extending up to 200 nm deep into the Si substrate. [ABSTRACT FROM AUTHOR]