This study examined the properties of Schottky-type diodes composed of Pt/TiO(2)/Ti, where the Pt/TiO(2) and TiO(2)/Ti junctions correspond to the blocking and ohmic contacts, respectively, as the selection device for a resistive switching cross-bar array. An extremely high forward-to-reverse current ratio of approximately 10(9) was achieved at 1 V when the TiO(2) film thickness was 19 nm. TiO(2) film was grown by atomic layer deposition at a substrate temperature of 250 degrees C. Conductive atomic force microscopy revealed that the forward current flew locally, which limits the maximum forward current density to < 10 A cm(-2) for a large electrode (an area of approximately 60 000 microm(2)). However, the local current measurement showed a local forward current density as high as approximately 10(5) A cm(-2). Therefore, it is expected that this type of Schottky diode effectively suppresses the sneak current without adverse interference effects in a nano-scale resistive switching cross-bar array with high block density.

A variety of major complications occur after intra-abdominal operations. Knowledge of when specific complications occur during the postoperative period would be useful in their diagnosis, prevention, and management. Our aim was to determine the incidence of major complications during specific postoperative intervals. Design: One thousand twenty-one patients undergoing intra-abdominal operations were studied postoperatively as part of a randomized clinical trial. Thirteen defined major complications were sought at the following specific intervals: less than 1, 1 through 3, 4 through 7, and 8 through 30 days after the operation. Setting: Cooperative trial from 15 Veterans Affairs medical centers.

The effect of anesthetic and postoperative analgesic techniques on perioperative outcome varies with the type of operation performed. Overall, epidural analgesia provides better postoperative pain relief. Epidural anesthesia and epidural analgesia improve the overall outcome and shorten the intubation time and intensive care stay in patients undergoing abdominal aortic operations.

The retention behavior of a HfO2 resistive switching memory device with a diameter of 28 nm and an ultra-thin (1 nm) HfO2 layer as the switching layer was examined. Ta and TiN served as the oxygen vacancy (VO) supplying the top and inert bottom electrodes, respectively. Unlike the retention failure phenomenon reported in other thicker oxide-based resistance switching memory devices, the current of both the low and high resistance states suddenly increased at a certain time, causing retention failure. Through the retention tests of the devices in different resistance states, it was concluded that the involvement of the reset step induced the retention failure. The pristine device contained a high portion of VO-rich region and the location of the border between the VO-rich and VO-free regions played the critical role in governing the retention performance. During the reset step, this borderline moves towards the Ta electrode, but moves back to the original location during the retention period, which eventually induces the reconnection of the disconnected conducting filament (in a high resistance state) or strengthens the connected weak portion (low resistance state). The activation energy for the retention failure mechanism was 0.15 eV, which is related to the ionization of neutral VO to ionized VO.

This study investigated the structural and electrical properties of (Ba,Sr)TiO3 (BST) thin film capacitors with thicknesses ranging from 18 to 215 nm, which were prepared by on- and off-axis rf magnetron sputtering technique on Pt/SiO2/Si substrates. The deposition rate and cation composition ratios of the films were controlled to be the same regardless of the sputtering geometry. All the films show elongations in the out-of-plane lattice spacing, suggesting the presence of compressive stress with a smaller value by on-axis sputtering than by the off-axis system. There was no thickness dependence of the strain in the polycrystalline BST films. The BST films deposited using the on-axis system showed a higher bulk dielectric constant with a higher interfacial capacitance and a lower leakage current level than the films produced by the off-axis system. The strain effect was proposed to explain the correlations between the structural and electrical properties.