The change of an internal stress in each layer consisting of AZO/Cu/Mo multilayer thin films with temperature were experimentally measured for the first time by using a grazing incidence X-ray diffraction (GI-XRD). These measurements were performed by taking account of relatively large difference of the total reflection values among AZO(2 wt%Al2O3 + ZnO), Cu and Mo, so that the structural properties of each layer of AZO/Cu/Mo tri-layer can be measured in turn by changing an incident angle of a GI-XRD. It was found that the stress mode of AZO, Cu and Mo single layers were compression, tension and tension, respectively. Their stress mode does not change even after forming multilayers and with successive anneals up to 400 degrees C. The internal stress of each layer in multilayer tends to decrease to accommodate each thermal mismatch among AZO, Cu and MO layers. It was demonstrated that the internal stress in each layer of the multilayer thin films had been measured with a nondestructive method by using a GI-XRD.

The internal stresses in an each layer of multiple layer's film (AZO, Cu, and Mo) has been measured experimentally using grazing incidence X-ray diffraction. This was performed utilizing the difference of total reflection values between consisting layers so as to be able to measure the each internal stresses in turn by the GISD.

Landesman et al., “Magnetic and XPS Studies of YBa2 Cu3O7-8 annealed in O2 Plasmas', AIP No. 165, Nov., 1987, pp. 389-396. Tamura et al., "Effects of a Plasma Oxidation of YBa2 CuO7-8 Films', ISEC, 1987, Aug. Thakoor et al., “Insulator Interface Effects in Sputter Deposited NbN/MgO/NbN (Superconductor-In sulator-Superconductor) Tunnel Junctions'. J. Vac. Soc. Technol. A5(4) 1987, p. 1721-1725. Ono et al., “Election Cyclotron Resonance Plasma Deposition Technique Using Raw Material Supply by Sputtering', Jpn. J. Appl. Phys. 23 (1984) L 534-536. Chi et al., “Superconducting A-15 Nb3Ge Films Pro duced by Reactive Evaporation', Thin Solid Films 72 (1980) pp. 285-290.

The resistivities of Al thin films with added Sc or Tb largely decrease at over 350 °C. They reach to 5 -7 μΩcm after annealing at 450 °C, together with the segregation of fine Al 3 RE (RE = Sc or Tb) metallic compounds. However, the temperatures at which resistivity starts to decrease largely are much lower for Al-SC alloy films (150 °C) than for Al-Tb ones (250 °C). Furthermore, thermal defects of hillocks or whiskers start to appear on the film surface after annealing at 200 °C and 450 °C for Al-Sc and Al-Tb alloy films, respectively. It was revealed that the further addition of Zr to these binary alloy films largely retards a large decrease of resistivities on annealing and enhances the formation of hillocks or whiskers. On the contrary, the addition of Cu to Al-Tb or Al-Sc films significantly suppresses the formation of thermal defects and shows relatively low resistivities after annealing at 350 °C.

The addition of Ho or Er to Al thin films markedly suppresses the grain growth at high temperature (350 °C - 450 °C). However, different from the effect of adding elements of Y, La, Pr, Nd, Sm, Gd, and Dy, thermal defects of hillocks or whiskers start to appear on the film surface after annealing at 300 °C (though depending on the content of added elements). It has been revealed that small amounts of metallic compounds of Al3RE (RE = Ho and Er) have been segregated in a supersaturated solid solution of the Al phase after annealing at 300 °C, and that a large amount of added impurities still remained in the Al matrix. The resistivity of Al1−xREx alloy thin films (RE = Ho or Er, x = 2 - 7 atomic %) was 5 - 7 μΩcm after annealing at 450 °C.

Dilute Cu-TM alloy films (TM = Ni, Ti, Mn, Zn, Mg) were investigated in order to develop interconnect lines with low resistivity, high thermal stability and high adhesion to a glass substrate for the installation of an advanced thin film transistor (TFT)-liquid crystal display (LCD). We found that among these added impurities, Zn showed the lowest resistivity 2.8 mu Omega cm by adding less than 1 at% on annealing above 350 degrees C. Most of these dilute Cu alloy films except for Cu-Zn and Cu-Mn alloys show the formation of thermally grown hillocks on annealing above 300 degrees C. It was also found that the dilute Cu-Zn alloy films showed the highest adhesion to a glass substrate among present alloy systems. The high resolution EDS analysis of the cross section of the films after the 400 degrees C anneal shows not only a large segregation of Zn atoms at the interface between film and glass substrate, but also a relatively high concentration of Zn atoms at both free surface and grain boundaries. However, any precipitation of oxides, such as ZnO was not observed at the interface between film and glass substrate by using a high resolution cross-section TEM analysis. We conclude from these results that the segregation of Zn atoms in Cu alloy systems plays a large role not only to increase an adhesion to a glass substrate, but also suppress the formation of hillocks at elevated temperatures.

The temperature dependent internal stresses distribution in depth for Al/Mo and Cu/Mo bilayer films were measured first time by using a grazing incidence X-ray scattering (GIXS) method. It was found that the residual internal stresses in each as-deposited layer film were tensile, and that there was a large stress gap at the interface between layers. These stress distribution profiles with depth in each layer were largely changed on annealing at an elevated temperature. Particularly, each internal stress at the interface between layers tended to change with each other so as to relieve a large stress gap at the boundary between layers. It was also revealed that there was a large difference in stress change at the interfaces on annealing between Al/Mo and Cu/Mo films.

Great attention has been directed toward the suppression of the formation of thermal defects such as hillocks and voids in interconnect lines during the thermal process of TFT-LCD or VLSI devices in order to improve their reliability and to get a high product yielding. It was revealed that these thermal defects can be suppressed largely by the segregation of adding impurities to form an intermetallic compound on the grain boundaries. The grain boundary segregation in dilute Al alloy thin films was investigated by employing an ab-initio molecular orbital calculation and the McLean-Guttmann theory. It was found that the calculated bond overlap population between like atoms was related closely to their reported bond energy values of diatomic molecules, while the calculated Homo level between unlike atoms also correlated linearly with the reported bond energy values. By using these correlations, we obtained the binding energies between constituent atoms in Al thin films. The trend of the grain boundary segregation of impurities in Al alloys was then assessed by a binary interaction coefficient energy calculated from the binding energies. We demonstrated that the calculated binary interaction coefficient energies showed fairly good agreement with the grain boundary segregation phenomenon of impurities in Al alloy thin films.

Annealing behavior of dilute Cu-X alloys (adding element X = transition metal and rare-earth metal with less than 3 at %) was investigated in terms of resistivity, internal stress, grain growth and hillock formation. The resistivity increases with addition of impurities regardless of kinds of adding elements. Generally, resistivity starts to decrease on annealing above 200 °C. Among present Cu dilute alloys, Sn addition shows the lowest resistivity 2.5 μΩcm on annealing at 400 °C. However, compared with a pure Cu film, salient grain growth of present dilute alloys does not takes place even at temperatures above 300 °C , where the grain size is nearly the same as that of as-deposited films. In-situ surface observation using an atomic force microscope (AFM ) revealed that hillocks did not grow on cooling stage (under tension), but started to form on heating stage (under compression). The scanning electron microscopy (SEM) observation of hillocks thus formed in present dilute alloy films shows that the external appearance of these defects was quite different from those observed in Al and Al alloy films. They most likely grow with a preferential crystal plane, not irregular growth like Al and Al alloy films. The internal stresses in most of the present as-deposited dilute Cu alloy films were nearly zero or compression of –25 to –100MPa, and upon annealing, they started to increase in tensile manner due to thermal stresses induced by the mismatch of the thermal expansion between substrates and deposited films. A large stress relaxation started to occur above 250°C, associating with a large number of hillock formation.

The in-situ resistivity measurement of partial crystalline amorphous ITO films was performed on annealing in various flowing gas atmospheres (air, O-2, H-2). It was found that an abnormal increase of resistivity showing a sharp peak was observed at 250 similar to 300 degrees C regardless of annealing gas atmospheres. The temperatures at the peak were shifted to higher range in the order of H2, air and 02 gases. The Hall measurement revealed that the carrier density and Hall mobility both sharply decrease at the resistivity peaks. The activation energy of the abnormal resistivity change was measured to be 0.6 similar to 0.9 eV by using the Kissinger's method, whose values are different depending on the annealing atmospheres. The X-ray diffraction profiles and TEM observations revealed that the crystallization took place at similar to 150 degrees C on a whole specimen area and their crystal grains continuously grew with further increase of annealing temperature. It was tentatively concluded that the realignment of Sn-O bond to generate a neutral (2Sn(In)(+)O(i)(2-))(x) complex was most likely responsible for the present abnormal resistivity change observed.

The establishment of all optical WDM network architecture suitable for applications with large capacity, long holding time and real time, such as video transmission, has important technical issues. However, most of the conventional system assumes static traffic and lacks the flexibility to unexpected change of traffic demand. Hence, the enhancement for dynamic traffic must be provided on the network design. In this paper, we propose a coupled-layer waveband routed network architecture to accommodate dynamic traffic changes. Assuming an environment without a wavelength converter, our coupled-layer waveband path design method is applied to several network topologies to enable an evaluation of its performance. The effectiveness and feasibility of this method were confirmed in terms of the number of required wavelengths and the blocking probability.

The stress distribution of (111) textured Cu films with depth was measured by using a GIXS method. We derived the equation to correct a scattering diffraction angle with depth, measured in the GIXS Seemann-Bohlin geometry, to obtain the actual scattering angle. It was revealed after the correction of the measured scattering angles that the internal stresses of (111) grains, on the whole, tend to increase almost linearly with increasing film depth from the free surface toward the substrate. It was suggested that these results were opposite to the results of the elastic calculation reported, and hence that a large stress relaxation took place during and/or after deposition and annealing. After annealing at various temperatures, these stress distribution profiles are almost unchanged, and are simply shifted uniformly in magnitude.

Indium tin oxide (ITO) films prepared by dc magnetron sputtering were annealed in air, vacuum, and oxygen gas atmospheres. The electrical properties and internal stresses of these annealed ITO films were systematically investigated. It was found that, among the above postannealing treatments, oxygen gas annealing significantly reduced both the resistivity and the internal stress in ITO films at fairly low temperatures of 100–150 °C. Resistivities and internal stresses as low as 7×10−4 Ω cm and 38 MPa, respectively, were obtained by annealing in oxygen gas atmosphere at 100 °C. It was also revealed that the (111) crystal orientation becomes dominant and that whole grains grow dramatically as a result of postoxygen annealing, even at 100 °C.

This study is concerned with an oral administration of 5mg of [1,2,4,19-13C(4),11alpha-2H]cortisol (cortisol-13C(4),2H(1)) to a human subject to reliably evaluate the individual activities of two isozymes of 11beta-HSD. The use of a GC-MS method allowed the simultaneous measurement of the plasma concentrations of cortisol-13C(4),2H(1), cortisone-13C(4), and cortisol-13C(4) together with endogenous cortisol and cortisone. The loss of 11alpha-2H during the conversion of cortisol-13C(4),2H(1) to cortisone-13C(4) by 11beta-HSD2 and the regenerated cortisol-13C(4) from cortisone-13C(4) by 11beta-HSD1 provided a direct and accurate means of distinguishing the activities of the two isozymes. The kinetic analysis associated with the metabolism of orally administered cortisol-13C(4),2H(1) was of great importance in assessing the 11beta-HSD activities. From a viewpoint of the chemical stability and much less pronounced kinetic isotope effect of the 13C-label and the 2H-labeling in the 11alpha-position, cortisol-13C(4),2H(1) used in this study served as an appropriate tracer for elucidating the kinetics of the interconversion of cortisol to cortisone in man.

Indium tin oxide (ITO) films prepared by d.c. magnetron sputtering were annealed in air, vacuum, and oxygen gas atmosphere. The electrical properties and internal stresses of these annealed ITO films were systematically investigated. It was found that, among the above post-annealing treatments, oxygen gas annealing significantly reduced both the resistivity and the internal stress in ITO films at fairly low temperatures of 100-150degreesC. Resistivities and internal stresses as low as 7 x 10(-4) Omega.cm and 38 MPa, respectively, were obtained by annealing in oxygen gas atmosphere at 100degreesC. It was also revealed that the (111) crystal orientation becomes dominant and that whole grains grow dramatically as a result of post-oxygen-annealing, even at 100degreesC.

Application to aluminum deposition using ion-plating method is described. This method has several superior features for generating highly (111) orientation. The origin of this orientation and surface roughness are discussed in connection with a kinetic energy of the ions. The film properties thus made were compared with those of a conventional sputtered film. The higher (111) oriented film showed high resistance against hillock formation even after annealing at high temperatures. An effect of a plasma cleaning of substrate surface was confirmed to be quite helpful for promotion of (111) preferred orientation.

We investigated the effects of adding Zr or Nb to Al thin films on the structure and resistivity changes during annealing to assess the potential use for TFT-LCD (thin-film-transistor liquid-crystal displays) Sate electrodes. These as-made alloy films (with 1.5-4.2 at% of added elements) show very fine grain less than 100nm in size and mainly consist of a highly supersaturated solid solution of the Al phase. The addition of Zr or Nb to Al thin films markedly suppresses the grain growth at high temperatures (350-450 degrees C), but thermal defects of hillocks or whiskers start to appear on the film surfaces after annealing at 250 degrees C. It was shown that small amounts of metallic compounds of Al3X (X = Zr or Nb) precipitated in a supersaturated solid solution of the Al phase after annealing at 350 degrees C, and that a large amount of added impurities still remained in the Al matrix. The resistivity of Al98.5Zr1.5 alloy films showed about 5 mu Ohm . cm after annealing at 450 degrees C.