Low-voltage-driven organic thin-film transistors (organic TFTs) with spatially controlled threshold voltages (−1.2 and −0.36 V) were fabricated for the first time. Using the microcontact printing method, tetradecylphosphonic acid (HC14-PA) and pentadecylfluoro-octadecylphosphonic acid (FC18-PA) were transferred to form ultrathin layers in different regions on a substrate. Together with plasma-grown aluminum oxide (AlOx) layer, the stamped layers were shown to have equal insulating ability as the dipped method monolayer. The feasibility of the area-selective stamping method was displayed using locally controlled inverter circuits. The shift of turn-on voltage for those transistors was consistent with the threshold voltage shift of the transistors.

We have successfully achieved a transconductance of 0.76 S/m for organic thin-film transistors with 4 V operation, which is the largest value reported for organic transistors fabricated using printing methods. Using a subfemtoliter inkjet, silver electrodes with a line width of 1 µm and a channel length of 1 µm were printed directly onto an air-stable, high-mobility organic semiconductor that was deposited on a single-molecule self-assembled monolayer-based gate dielectric. On reducing the droplet volume (0.5 fl) ejected from the inkjet nozzle, which reduces sintering temperatures down to 90 °C, the inkjet printing of silver electrodes was accomplished without damage to the organic semiconductor.

We have investigated structural changes of amorphous borosilicon carbonitride materials with atomic ratios of B/Si/C of 2/3/6 and 4/3/6 calcined at several temperatures. The boron K-edge x-ray absorption spectra showed that the structures of both hexagonal boron nitride ([BN3] unit) with nitrogen-void defects ([BN2] and [BN1] units) and boron oxide existed in the samples, and the relative peak intensity due to the [BN3] unit became stronger by increasing the calcined temperature. It is thought that the well-developed B–N chain and the borosilicate glass coating lead to the high resistance to oxidation at high temperature. X-ray diffraction and infrared measurements followed the x-ray absorption near-edge spectroscopy findings.

Bi2Te3-based thin films were fabricated on glass substrates by the pulsed laser deposition (PLD) method. The vapor pressures of Bi and Te are significantly different, so controlling the stoichiometric composition is difficult when using conventional physical vapor deposition techniques, and the thermoelectric properties of Bi2Te3 films are sensitive to the film composition. PLD is a promising technique for the fabrication of telluride-based films such as Bi2Te3 due to its superior capability for controlling the film composition. Another advantage of PLD is the flexibility that it allows in terms of atmosphere in the reaction chamber; high concentrations of gases such as oxygen or argon can be introduced. We have measured various compositions of Bi2Te3 based films, and have identified the optimal compositions for both n-type and p-type material. The thermal conductivities of these Bi2Te3 films were evaluated by an exact measuring system, and the results were twice as low as those of conventional bulk materials. These results suggest that PLD has significant advantages for the deposition of in-plane Bi2Te3-based thin films.

In this paper we describe a new attempt of high-throughput screening of thermoelectric materials by combining the use of the “bulk composition-spread (CS)” or “bulk diffusion multiples (DM)” and the “scanning thermal probe microanalyzer (STPM).” The (Bi2Te3)1-x(Sb2Te3)x (0<x<1) and Ni1-xCux (0<x<1) bulk CS samples were prepared by conventional powder metallurgy method by using mechanical alloying and spark plasma sintering process. The Ni-Cu-X (X=Sn, In, Bi.) DM sample was prepared by post-heating of the CS samples in a molten metal. The two dimensional distributions of Seebeck coefficient and the thermal conductivity of the cross section of the CS and DM samples which composed of graded composition were visualized by using STPM at room temperature. The composition variation was checked by EDX. The relationship between composition and the thermoelectric properties was successfully determined by using the mapping results. The time required for mapping out the 100x100 pixel image was 8 to 11 hours. The total time required for this set of the screening experiment, from sample preparation to the final conclusion, was within 24 hours. For samples Ni-Cu-X DM the diffusion length of the elements at the interface can be large as 1mm and it was found that STPM is applicable to visualize the thermoelectric properties at the region of interest.

The thermoelectric properties of Ni1-xCux (0<x<1) alloy are measured from 323K to 950K. The sample with optimized composition, Ni70Cu30 is found to possess large power factor value of 0.012 Wm−1K−2 at around 950K. Estimated figure of merit value ZT is 0.21 for Ni50Cu50 and 0.18 for Ni70Cu30 at the same temperature. A novel attempt of high-throughput parallel synthesis using multiple-wells is carried out to test the feasibility of combinatorial approach in this material system. The Seebeck coefficient is visualized over the multiple-wells combinatorial library and the other Ni-Cu composition-spread, and it is proved that further enhancement of throughput could be possible by conducting systematic experiments based on the combinatorial approaches performed in this study.

By means of an optical tracer-particle tracking method, measurements for Lagrangian characteristics of turbulence, including the mean-square value of lateral diffusion from a point source $\overline{Y^2}$, the r.m.s. value of fluctuating velocity v′, the velocity autocorrelation coefficient RL(τ), and the integral scale ΛL, were made in approximately isotropic turbulent flow behind a grid. Comparison of these Lagrangian data with the Eulerian integral scale Λf and the double velocity correlation coefficient f(r) led to the following results: (i) for a moderate turbulent Reynolds-number range of Reλ = 20 − 70, the ratio β(= ΛL/Λf) is within the values of 0.6 – 0.3, becoming lower as Reλ increases, and (ii) the distribution of RL against time lag τ is analogous to that of f against βr/v′. Further, it was confirmed by both theoretical analysis and experiments that the growth of $\overline{Y^2}(t)$ was weakened by the decay of turbulent energy, particularly so for long diffusion times.

In every wafer processing step wafer stress management is extremely important for advanced device manufacturing. Thermally induced stress on device wafers has a large impact on lithography and affects device yield. Thermally induced stress during rapid thermal annealing (RTA) steps in high density 512MB DRAM device fabrication was investigated using a lamp-based (cold wall) RTA system and compared to results using a furnace-based (hot wall) single wafer RTA system. Compared to the lamp-based (cold wall) system, RTA in a furnace-based (hot wall) system was found to be very effective in suppressing thermally induced stress and increasing device yield due to superior pattern transfer characteristics in lithography.

In order to clarify the effect of bias treatments on the highly oriented growth of diamond, we investigated the relation between the silicon surface morphology changes after applying a bias voltage, and the orientation of the diamond crystallites after growth. We report two major findings. First, a textured structure on the Si surface after the bias pretreatment was found to be a necessary but insufficient indicator for the subsequent growth of highly oriented diamond. Second, although bias pretreatments effectively enhance nucleation, we did not find a clear relationship between the nucleation density and the percentage of oriented crystallites. The highest nucleation densities resulted in randomly oriented films. We conclude that bias pretreatments affect the nucleation enhancement and the diamond orientation through different mechanisms.

We report a case of recurrent laryngeal papillomatosis which developed into laryngeal squamous cell carcinoma 11 years after the first diagnosis. Interestingly, we could identify HPV type 18 DNA in the carcinoma tissue using the polymerase chain reaction (PCR). Other known risk factors of irradiation, smoking, exposure to chemical agents, or a hereditary tendency to malignant tumours were not present in this case. Our finding suggests that HPV type 18 is another aetiological agent for laryngeal carcinoma.

We show that the variation of the structural unit in tellurite glasses is due to the charge transfer from modifier atoms to TeO6 octahedra with use of first-principles molecular orbital calculations. Orbital overlap population analysis reveals that the transferred electrons to the Te- O antibonding orbital cause breaking Te-O bonds and lead to reducing the coordination number of the Te atom.

Eight cases of adenoid cystic carcinoma were reviewed to determine whether and how the histological features of the tumour vary with the progress of the disease. The tumours were classified by their histological patterns as tubular, cribriform, trabecular or solid. The relative amount of each pattern seen in routine light microscopic sections was calculated histomorphometrically and compared in the primary tumour and recurrent and/or metastatic lesions in the same case. In the early stage, the tubular pattern predominated. Later, the highest percentage shifted to the cribriform, then to the trabecular and finally, in the late stage, to the solid pattern. There was no reverse direction of histological transformation from the solid to the tubular pattern. These results may help to explain previous reports that the tubular pattern usually represents a favourable prognosis, the solid pattern a poor prognosis and the cribriform pattern an intermediate prognosis.

Specimens of borosilicate glass were irradiated in a material testing reactor at a neutron fluence of 1019–1020 nvt and a temperature of below 250°c. Tritium released from the specimen was determined by means of a specially designed sampling system and liquid scintillation counter.

Temperature and time dependence of the releasing behavior of tritium from borosilicate glass was obtained in the temperature range of 200 – 700°C. Very small amount of tritium as compared with the amount contained in the specimen was released in several hours at temperatures below 700°C. The greater part of tritium released from the specimen was tritium oxide, which is controlled by the diffusion step of tritium in the specimen. The diffusion coefficient of tritium in borosilicate glass was also obtained, which agreed with that of water in glasses.