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The synthesis, processing and electrical characterization of thin nanostructured thin films of barium titanate (BaTi[O.sub.3]) built from uniform nanoparticles are reported. The nucleation-mediated method is presented in terms of added degrees of control in the manipulation of thin film properties, where the nanoparticles can be used as initial building blocks for the preparation of thin films that display highly uniform nanostructured texture and grain sizes.

We present complete experimental determinations of the tunnel barrier parameters (two barrier heights, junction area, dielectric constant, and extrinsic series resistance) as a function of temperature for submicrometer Ni--NiO--Ni thin-film tunnel junctions, showing that when the temperature-invariant parameters are forced to be consistent, good-quality fits are obtained between I--V curves and the Simmons equation for this very-low-barrier system (measured [empty set] [approximately equal to] 0.20 eV). A splitting of [approximately equal to] 10 meV in the barrier heights due to the different processing histories of the upper and lower electrodes is clearly shown, with the upper interface having a lower barrier, consistent with the increased effect of the image potential at a sharper material interface. It is believed that this is the first barrier height measurement with sufficient resolution for this effect to be seen. A fabrication technique that produces high yields and consistent junction behavior is presented as well as the preliminary results of inelastic tunneling spectroscopy at 4 K that show a prominent peak at -59 meV, shifted slightly with respect to the expected transverse optic phonon excitation in bulk NiO but consistent with other surface-sensitive experiments. We discuss the implications of these results for the design of efficient detectors for terahertz and IR radiation. OCIS codes: 240.7040, 160.3900, 040.3060, 040.5160, 130.0250, 190.4360.

Reliability and robustness of low-k materials for advanced interconnects has become one of the major challenges for the continuous down-scaling of silicon semiconductor devices. Metal catalyzed time dependent breakdown is a major force preventing integration of sub-32 nm process technology nodes. Here, the authors demonstrate that ions can behave as trapping points for charge carriers. A mechanism for describing trapping of charge carriers into mobile ions under bias and temperature stress is presented. Charge carrier confinement into ionic center was found to be dominated by ionic transport. After extended bias and temperature stress, the magnitude of charge trapping into ionic centers decreased. Simulations suggest that built-in fields could reduce the effect of externally applied fields in directing ionic drift, therefore inhibiting the trapping mechanism. This work depicts the dual role of ionic species when catalyzing dielectric failure (mobile defect and local field distortion). [ABSTRACT FROM AUTHOR]

An experimental study is presented to probe the interface barriers of dopant-segregated silicide–Si diodes with internal photoemission. The spatial information of the interface dipoles, which is believed to be the cause of the effective Schottky barrier height (SBH) modification, is extracted from the field dependence of the barrier heights. A clear difference between the dopant segregation (DS) junctions and a pure Schottky junction is found: Boron DS modifies the effective SBH by forming a \p^+\- \n junction while arsenic DS forms a “Shannon” junction with a fully depleted 1.5-nm doping depth in front of the silicide. [ABSTRACT FROM AUTHOR]

A new technique for directly fabricating patterned thin films (<1 μm thick) of fully single-crystal strontium titanate uses deep H+ implantation into the oxide sample, followed by anodic bonding of the sample to a Pyrex or Pyrex-on-Si substrate. The dielectric properties and crystal structure of such thin films are characterized and are found to be essentially those of the bulk single crystal. [ABSTRACT FROM AUTHOR]

Near-infrared detectors based on metal-insulator-metal tunnel junctions integrated with planarized silicon nanowire waveguides are presented, which we believe to be the first of their kind. The junction is coupled to the waveguide via a thin-film metal antenna feeding a plasmonic travelling wave structure that includes the tunnel junction. These devices are inherently broadband; the design presented here operates throughout the 1500-1700 nm region. Careful design of the antenna and travelling wave region substantially eliminates losses due to poor mode matching and RC rolloff, allowing efficient operation. The antennas are made from multilayer stacks of gold and nickel, and the active devices are Ni-NiO-Ni edge junctions. The waveguides are made via shallow trench isolation technology, resulting in a planar oxide surface with the waveguides buried a few nanometres beneath.The antennas are fabricated using directional deposition through a suspended Ge shadow mask, using a single level of electron-beam lithography. The waveguides are patterned with conventional 248-nm optical lithography and reactive-ion etching, then planarized using shallow-trench isolation technology. We also present measurements showing overall quantum efficiencies of 6% (responsivity 0.08 A/W at 1.605 mum), thus demonstrating that the previously very low overall quantum efficiencies reported for antenna-coupled tunnel junction devices are due to poor electromagnetic coupling and poor choices of antenna metal, not to any inherent limitations of the technology.