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In low temperature experiments, resins have many applications as glues or thermal and electrical insulators. Cyanate ester resins (CEs) are a high-temperature compatible thermoset resin whose glass-transition temperature $T_g$ is ~300 $^\circ$C. Recently, we found that CEs also withstand low temperatures without microcracking by measuring $^4$He permeability. Here, we measured specific heat C, thermal conductivity \kappa, and magnetic susceptibility $\chi$ of different kinds of CEs in the wide temperature range from room temperature to 0.5 K for C and 2 K for other two. The thermal properties, C and \kappa, of different kinds of CEs are surprisingly coincident with each other. We discuss chemical structures and crystallinity of CEs and their blends based on the measured thermal properties. Compared to Stycast 1266, a commonly-used epoxy resin in low temperature experiments, C of CEs is larger by a factor of 3 (, Comment: 7 pages, 10 figures

Cyanate ester (CE) thermoset is a polymer with a high glass-transition temperature of ≈ 300 °C. CE is expected to be an alternative to Stycast 1266 as a sealing and casting glue for low temperature experiments, especially for adsorption experiments where baking of the substrate at T > 100 °C before cooling is required to eliminate surface contaminations. We experimentally confirmed that thermosets of CE monomers are non-porous and absorbs/desorbs water very little from measurements of (1) 4He permeation properties at temperatures from room temperature (RT) to 77 K and of (2) weight gains (δW) after storage for days in water and in air at RT. The 4He permeation is rather large at RT but negligibly small at T 130 K where the diffusion constant of 4He in CE is vanishingly small. δW in water and air are 0.3–0.5% and 0.5–1.0%, respectively, which are much smaller than those of Stycast 1266. Therefore, cyanate ester is an excellent alternative to commonly used epoxy resins especially in surface-sensitive experiments at low temperature.

EPR spectra originating from phosphorus shallow donors occupying silicon sites in 3C-, 4H-, and 6H-SiC are identified by using CVD grown films in which the interference from the signals from the nitrogen shallow donors is practically absent. Phosphorus donors occupying both silicon and carbon sites are observed in high-energy phosphorus ion implanted semi-insulating 6H-SiC which was also free from the interference from the signals from the nitrogen shallow donors.

Electrical characteristics of n-type diamond Schottky diodes and metal/diamond interfaces have been systematically investigated for phosphorus (P)-doped homoepitaxial diamond layers. The current-voltage (I-V) characteristics of the Ni/n-type diamond Schottky diode show excellent rectification properties from 297 K to 773 K. The ideality factor and the rectification ratio were 1.0 and ∼10 6 at +10 V at 573 K, respectively. The rectifying properties deteriorated with increasing P concentration in the diamond layers. Temperature-dependent capacitance-frequency (C-f) and conductance-frequency (G-f) measurements on the Schottky diodes have shown that the capacitance is reduced at high frequency due to the inability of deep centers to maintain an equilibrium ionization state under a high-frequency modulation. C- V measurements deduced that the P electrical activity (the ratio of the net donor concentration to the P concentration) was nearly 1 from low concentration (1.6 x 10 16 cm -3 ) to high concentration (2.7 x 10 18 cm -3 ) of P. The Schottky barrier height was found to be almost constant at ∼4.3 eV independent of the metal work function (Ni, Pt, Al and Ti).

We develop a web-based database system for electron paramagnetic resonance (EPR) centers in semiconductors. This database is available to anyone at http://www.kc.tsukuba.ac.jp/div-media/epr/ . It currently has more than 300 records of the spin-Hamiltonian parameters for major known EPR centers. One can upload own new records to the database or can use simulation tools powered by EPR–NMR © . Here, we describe the features and objectives of this database, and mention some future plans.

Phosphorus shallow donors having the symmetry lower than T d are studied by pulsed EPR. In diamond:P and 3 C –SiC:P, the symmetry is lowered to D 2 d and the density of the donor wave function on the phosphorus atom exhibits a predominant p-character. In 4 H –SiC:P with the site symmetry of C 3 v , the A 1 ground state of the phosphorus donors substituting at the quasi-cubic site of silicon shows an axial character of the distribution of the donor wave function in the vicinity of the phosphorus atom.

Electrical properties of phosphorus (P)-related donors have been investigated for P-doped homoepitaxial diamond layers grown by microwave plasma CVD. Temperature-dependent current–voltage (I–V), capacitance–voltage (C–V) measurements and frequency-dependent C–V measurements have been carried out with lateral dot-and-plane (with ring-shaped gap) Schottky barrier diodes. N-type Schottky junction properties were obtained. The ideality factor and the rectification ratio of the Schottky junction were obtained to be 1.9 and 1.7×105 at ±10 V and 473 K, respectively. Frequency-dependent measurements on these Schottky barrier diodes have shown that the capacitance is reduced at high frequency, most likely due to the inability of deep centers to maintain an equilibrium ionization state under a high-frequency modulation. C–V measurements deduced that the net donor concentration was 6.2×1017 cm−3 and the corresponding built-in potential was 4.0 eV, when the P concentration was 8.3×1017 cm−3. Phosphorus electrical activity was 0.75 in the P-doped diamond layer. The carrier thermal activation energy (the donor level) was evaluated to be 0.6 eV from the relation between the net donor concentration and the carrier concentration.

Electron spin resonance technique has been applied to characterize defects and to determine local structure of phosphorus in phosphorus-doped (111)-homoepitaxially grown CVD diamond films. Dominant defects have g-value similar to that of the H1 center in polycrystalline CVD diamond, however, are not accompanied with a unique nearby hydrogen atom. These defects are likely to be located near substrate/ epilayer interface. New phosphorus related center with a tetragonal symmetry has been found.

It has traditionally been thought that animals can utilize ammonia for amino acid biosynthesis, and that for them some amino acids are nutritionally nonessential. Presumably this idea originates from the notions of Schoenheimer (G. L. Foster et al. [1939] J. Biol. Chem. 127, 319-327) and of Rose (W. C. Rose et al. [1948] J. Biol. Chem. 176, 753-762), which we question for the following reasons. First, Schoenheimer's experiments only showed the incorporation of ammonia into amino acids. This may occur simply as an exchange between ammonia and the alpha-amino group of endogenous amino acids and reflects the enzymatic properties of glutamate dehydrogenase, which is a reversible enzyme. Second, Rose's nutritional experiments were concerned with whether carbon skeletons of particular amino acids can (nonessential) or cannot (essential) be synthesized from common intermediates of carbohydrate metabolism. We propose that mammals, living as they do at the top of the food web, are absolutely dependent directly or indirectly on higher plants and microorganisms for preformed alpha-amino nitrogen per se and that the first joining of C- and N-atoms to make glutamate constitutes a basic anabolic system in nature after the fixation of CO2 and N2.

An intercalation process for narrow graphene interconnects with linewidths of 5 µm size induced partial delamination of the graphene layers and insufficient intercalation in some graphene interconnects with linewidths of

We have developed a CMP process providing a short polishing time and sufficient uniformity that is applicable to 300 mm scale carbon nanotube (CNT) via integration. To achieve our target, we have developed a new CMP process to make selectively grown CNT in a via hole. Spin on carbon (SOC)film was coated to protect nickel (Ni) catalyst and titanium nitride (TiN) film inside the via hole during SOC-CMP. The SOC-CMP process was used to perform two-step polishing to remove Ni catalyst and TiN film from the field area. CNT-CMP polishing time was reduced from 1690 sec to 200 sec and the yield ratio improved to 100%. CNT-CMP performance improved to a level usable for practical use by selectively growing CNT only from the via. We also evaluated the behavior of CNT-CMP during polishing using a damascene pattern wafer. Step height (Step height means a step between the wiring area and field area) occurred when CNT-SOG (spin-on glass) composite film was appeared upper the via hole but was reduced by concentrating the polishing pressure to project the CNT-SOG composite film. This result indicates that CNT-SOG composite film was polished by mechanical force.

Graphene is a promising material to replace copper interconnect metallization under 10 nm in width. We report a method for evaluating graphene interconnect wiring structure by conductive atomic force microscopy (C-AFM), which enables direct measurement of the 2D-resistance distribution and coverage evaluation of multilayer graphene (MLG) grown on Ni interconnects using a 300 mm damascene process. It is demonstrated that the coverage of MLG upon Ni can be estimated more precisely by C-AFM than that by back-scattered electron scanning electron microscopy (BSE-SEM) observation. We also measured the resistance of the MLG/Ni conductor and confirmed conduction paths of the MLG/Ni interconnect. Process dependence of MLG shows that lower local resistance corresponds to higher G band and D band intensity ratio (G/D ratio) in Raman spectra. C-AFM is demonstrated to be a potential technique for local conductance evaluation of next generation interconnects.

We fabricated a carbon nanotube (CNT) via structure on a 300-mm wafer. We investigated the CNT chemical-mechanical polishing (CNT-CMP) behavior in an actual via pattern structure and clarified the technical issues of the CNT-CMP process. We developed a fabrication process of CNT via structures using selective CNT growth, which has a high potential for applying CNTs to high aspect ratio via structures.

SUMMARY Seven unialgal cultures of picoplanktonic cyanobacteria isolated from freshwater lakes in Japan were examined in the present study. They are assignable to the Cyanobium cluster of the Synechococcus group sensu Waterbury and Rippka (1989) based on morphology, GC content, fatty acid and quinon compositions. They include one blue-green colored strain (NIES-680) with only phycocyanin as well as the PCC strains of Cyanobium cluster (Waterbury and Rippka 1989) and six reddish colored strains (NIES-715, -717, -718, -721, -722 and -723) with both phycocyanin and phycoerythrin. All the strains examined developed colonies in pour-plates I of 1.4%‘ultra-low-gel-ling-temperature agarose’within 1 month. The colony numbers were 12–20 × 102 c.f.u. mL-1. Most clones derived from the colonies were axenic by the bacteria-free check. The length of this procedure, preculture excepted, was 4–6 weeks. Colony formation in pour-plate II of 0.6% agarose was observed in the blue-green strain (NIES-680) and the three reddish strains (NIES-717,-721 and -723) after 1–2 months. The number of colonies formed on pour-plate II were 1–2 × 102 c.f.u. mL-1, much lower than those on pour-plate I. Only a blue-green strain formed colonies on spread plates of 0.6% agarose. The colony numbers developed were 10–15 × 102 c.f.u. mL-1 and similar to those on pour-plate I. The other reddish strains did not develop colonies on spread plates. The pour-plating method developed provides a highly efficient and successful method for obtaining axenic clonal cultures of planktonic cyanobacteria.

We fabricate multilayer graphene interconnects with 100-nm-class line widths. Multilayer graphene is grown on a Ni catalyst layer using remote plasma-enhanced chemical vapor deposition (CVD) at a low temperature of 600°C and transferred onto a SiO2/Si substrate after exfoliation from the Ni layer. The sheet resistance of the CVD graphene interconnects is as low as 500 Ω sq. The temperature dependence of resistance reveals that the CVD graphene exhibits half-metallic transport properties.

We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. We use Hartmann-Hahn double resonance to coherently enhance the signal from a single nuclear spin while decoupling from the noisy spin-bath, which otherwise limits the detection sensitivity. As a proof-of-principle we: (I) observe coherent oscillations between the NV center and a weakly coupled nuclear spin, (II) demonstrate nuclear bath cooling which prolongs the coherence time of the NV sensor by more than a factor of five. Our results provide a route to nanometer scale magnetic resonance imaging, and novel quantum information processing protocols.

We investigated doping material selection for multilayer graphene (MLG) interconnects and a passivation process to stabilize the doped state. Intercalation doping with Br2, FeCl3, and MoCl5 was compared in terms of doping ability and robustness against environmental effects, which are exacerbated by miniaturization. We found that MoCl5 was advantageous for miniaturization. We hypothesized that environmental stability would be enhanced by partially oxidizing MoCl5 and avoiding hydrolysis by water vapor in air. To test this, we examined a passivation process by dry oxygen exposure. We verified that the doping effect was improved and that intercalated material (MoCl5) was partially oxidized and confined in the MLG.

Lightly phosphorus-doped {111} homoepitaxial diamond films have been grown by microwave plasma-assisted chemical vapor deposition under optimized growth conditions. The Phosphorus concentration in the film can be controlled at a low doping level of the order of 1016cm−3. N-type conductivity of the films with phosphorus concentrations above 1×1016cm−3 is reproducibly confirmed by Hall-effect measurements in the temperature range from 300to873K. The highest value of the Hall mobility at room temperature is 660cm2∕Vs obtained for a film with a phosphorus concentration of 7×1016cm−3.

There is still much to be learned regarding the nature of the interaction between lexical tone and utterance-level intonation. Previous studies in individual languages tend to be too narrow, focusing on ways to model the final F0 output without regard to cross-linguistic implications; studies mainly concerned with phonological patterns across languages tend to over-generalize, missing or glossing over many language-specific and category-specific phenomena. This dissertation attempts to address the gap left by these previous studies. The first part of the dissertation presents results from a series of production and perception experiments conducted for a handful of tone languages, including Standard Mandarin, Henanhua, Cantonese, North Kyeongsang Korean, and Kansai Japanese (a family of dialects including Shiga, Kyoto, Osaka, and Kobe Japanese). The production experiments were designed to elicit multiple renditions of various lexical tones in declarative and echo question contexts, and the perceptual experiments were designed to test the degree of recoverability for each communicative function (lexical tone and utterance-type intonation) in the various conditions. The second part of the dissertation considers the implications of the experimental results for building a comprehensive model of speech melody. First, by examining the behavior of intonation across tonal categories within each language, it is shown that there is evidence for unpredictable tone-dependent intonation implementation, suggesting that our model must allow for some interaction between the two at some level before phonetic implementation (a principle taken for granted by some models and ruled out by others). In addition, the results are assessed cross-linguistically, characterizing the ways in which the model must be parameterized. Finally, an enhanced autosegmental-metrical model that meets both of the above demands is proposed. The model includes an autosegmental geometry that encodes lexical tones in languages like Mandarin and Cantonese as tunes associated with syllables and so-called “accentual melodies” in languages like Kansai Japanese and NKK as tunes associated with words. The scope of a given melodic unit’s effect on an utterance is determined by the level(s) of the prosodic constituent(s) with which it is associated., This dissertation is copyright 2013 by the author. This paper is copyrighted, and is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) - see https://creativecommons.org/licenses/by-nc-nd/4.0/

The Urban Expressways should be designed as a regional symbol to consider the landscape and the environment. The image is difficult to be described with linguistic expression as impacts given by regional mentality and surrounding factors. Therefore “the colour” is introduced to describe them in terms of information of planning. In the study, Neural Network (NN) Models are used to analyze the relation between “Environmental factors and the colour image” as well as “the colour image and degree of preference.” And also the evaluation of the road network is carried out as the combination of the colour images of consistent routes. The genetic algorithm involving NN model provides the future ideal image of the roads.

Ohmic contacts with low contact resistivity were formed on phosphorus-doped n-type {111} diamond thin films grown by microwave-plasma chemical-vapor deposition. Heavily-doped diamond layers were selectively grown on a diamond substrate by covering a part of substrate surface with a titanium/gold layer. Gold contacts deposited directory on a lightly phosphorus-doped diamond showed a rectification characteristic, while those formed on the selectively grown, heavily doped diamond layers showed an Ohmic characteristic. The Ohmic property of contacts formed with the heavily doped layers was found to be independent of the metals. It is therefore concluded that the tunneling current dominates carrier transport at the interface between the metal and the heavily doped n-type diamond.

We have succeeded in fabricating ultrafine carbon nanotube (CNT) via interconnects with SiOC interlayer dielectrics. High-quality multiwalled CNTs are grown in via holes with a diameter of 70 nm using pulse-exited remote plasma-enhanced chemical vapor deposition at 450 °C. The resistance of a 70-nm-diameter CNT via is 52 Ω, which is the lowest ever reported for CNT via interconnects. The CNT via interconnect has the capability to sustain current density as high as 1×108 A/cm2.

In a survey of biochemistry textbooks and reviews, we encountered problems, on the glutamate metabolism in animals. From the perspective of both basic mammalian biochemistry and the world’s major nutritional problems we urge that all textbooks and relevant reviews address the issue of glutamine/glutamate metabolism more clearly and appropriately.

Multiwalled carbon nanotubes (CNTs) have been grown by remote plasma-enhanced chemical vapor deposition at temperatures as low as 400 °C. In via formation, the selective growth of CNT bundles in via holes at 430 °C and chemical mechanical polishing for planarization have been performed. The electrical evaluation of CNT single vias with various diameters reveals that the via resistance is inversely proportional to the via area. This result indicates that the CNTs are grown with uniform quality and density in the via holes with various diameters and stable contact formations are obtained. Moreover, the resistances of single vias are approximately equivalent to the via resistances estimated from the resistances of via chains, demonstrating the via-to-via uniformity of the CNT vias obtained by the remote plasma-enhanced chemical vapor deposition.

Graphene is a promising material to replace Cu-interconnect metallization under a width of 10 nm. We report a method for evaluating the graphene interconnect wiring structure by conductive atomic force microscopy (C-AFM), which enables the direct measurement of the two-dimensional (2D) resistance distribution and the coverage evaluation of multilayer graphene (MLG) grown on Ni interconnects using a 300 mm damascene process. The resistivity of exfoliated two-layer graphene was measured and a reasonable value of 30 µΩcm was obtained. We also measured the resistance of the MLG/Ni stack of 350 nm L/S patterns and confirmed the conduction paths of the MLG/Ni stack. It is demonstrated that the coverage of MLG on Ni interconnects can be estimated more precisely by C-AFM than by backscattered electron scanning electron microscopy (BSE-SEM) observation. C-AFM is demonstrated to be a potential technique for the local conductance evaluation of next-generation interconnects.

Continuous-wave (cw) electron paramagnetic resonance (EPR) at both $X$-band and $W$-band frequencies, pulsed-EPR, and pulsed electron nuclear double resonance (ENDOR) were used to study phosphorus shallow donors in $3C$-, $4H$-, and $6H\text{\ensuremath{-}}\mathrm{SiC}$ doped with phosphorus (P) during chemical vapor deposition (CVD) growth. In $3C\text{\ensuremath{-}}\mathrm{SiC}$, a spectrum with ${D}_{2d}$ symmetry and the principal $g$ values, ${g}_{\ensuremath{\Vert}}=2.0051$, ${g}_{\ensuremath{\perp}}=2.0046$, was detected. The $^{31}\mathrm{P}$ hyperfine (hf) constants of the center, ${A}_{\ensuremath{\Vert}}=0.53\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$ and ${A}_{\ensuremath{\perp}}=\ensuremath{-}0.13\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, were determined from pulsed-ENDOR measurements. A doublet with ${C}_{3\mathrm{v}}$ symmetry (${g}_{\ensuremath{\Vert}}=2.0065$, ${g}_{\ensuremath{\perp}}=2.0006$, and $^{31}\mathrm{P}$ hf constants ${A}_{\ensuremath{\Vert}}=8.24\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, ${A}_{\ensuremath{\perp}}=5.89\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$) was detected in P-doped $4H\text{\ensuremath{-}}\mathrm{SiC}$. In the $6H$ polytype, the same ${\mathrm{P}}_{1}$ and ${\mathrm{P}}_{2}$ doublets [Greulich-Weber, Phys. Status Solidi A 162, 95 (1997)] or $d{\mathrm{P}}_{\mathrm{h}}$, $d{\mathrm{P}}_{\mathrm{c}1}$, and $d{\mathrm{P}}_{\mathrm{c}2}$ doublets [Baranov et al., Phys. Rev. B 66, 165206 (2002)] previously reported in material doped with P by neutron transmutation were detected. Our cw-EPR, two-dimensional EPR, and electron spin-echo envelope modulation (ESEEM) results confirm that the $d{\mathrm{P}}_{\mathrm{c}1}$ and $d{\mathrm{P}}_{\mathrm{c}2}$ doublets are related to different allowed and forbidden transitions of the ${\mathrm{P}}_{2}$ center with $S=1∕2$ and $I=1∕2$. Based on the observed $^{31}\mathrm{P}$ hf interaction (for three polytypes) and the $^{13}C$ hf interaction with nearest neighbors (for $4H$- and $6H\text{\ensuremath{-}}\mathrm{SiC}$), the P-related spectra are assigned to the ground states of the isolated shallow P at Si site. The valley-orbit splitting of the shallow P donors was estimated from the temperature dependence of the spin-lattice relaxation time and of the cw-EPR signal intensities. Based on the ab initio supercell calculations of the spin localizations on the P atom and the nearest C neighbors in $4H\text{\ensuremath{-}}\mathrm{SiC}$ and the similarity between the spectra in the $4H$ and $6H$ polytypes, we reassign the spectrum in $4H\text{\ensuremath{-}}\mathrm{SiC}$ to the shallow P donor at the quasicubic site $({\mathrm{P}}_{\mathrm{k}})$ and the two doublets ${\mathrm{P}}_{1}$ and ${\mathrm{P}}_{2}$ in $6H\text{\ensuremath{-}}\mathrm{SiC}$ to the shallow P donors at two quasicubic sites, ${\mathrm{P}}_{\mathrm{k}1}$ and ${\mathrm{P}}_{\mathrm{k}2}$, respectively.

In this brief review, I recollect my experiences of how the studies of pyrocatechase and salicylate hydroxylase led to the isolation and revelation of P450cam. Those experiences were instrumental in the separation, purification, and characterization of the two forms of adrenal cortex mitochondrial P450.

In this article, we advocate the radical revision of the 20th-century version of amino acid metabolism as follows. (1) Classic studies on the incorporation of [15N]ammonia into glutamate, once considered to be an epoch-making event, are not distinctive proof of the ability of animals to utilize ammonia for the synthesis of alpha-amino nitrogen. (2) Mammalian glutamate dehydrogenase has been implicated to function as a glutamate-synthesizing enzyme albeit lack of convincing proof. This enzyme, in combination with aminotransferases, is now known to play an exclusive role in the metabolic removal of amino nitrogen and energy production from excess amino acids. (3) Dr. William C Rose's "nutritionally nonessential amino acids" are, of course, essential in cellular metabolism; the nutritional nonessentiality is related to their carbon skeletons, many of which are intermediates of glycolysis or the TCA cycle. Obviously, the prime importance of amino acid nutrition should be the means of obtaining amino nitrogen. (4) Because there is no evidence of the presence of any glutamate-synthesizing enzymes in mammalian tissues, animals must depend on plants and microorganisms for preformed alpha-amino nitrogen. This is analogous to the case of carbohydrates. (5) In contrast, individual essential amino acids, similar to vitamins and essential fatty acids, should be considered important nutrients that must be included regularly in sufficient amounts in the diet.

Adrenal P-450 activities were measured by an in vitro reconstitution system from tissues obtained from human aldosteronomata, and the results compared with those of the normal adrenal tissues from patients with Grawitz's tumor. The P-45011 beta activity was significantly increased in adenoma tissue (55.6 +/- 5.3 vs 9.0 +/- 6.2 nmol corticosterone/mg of protein/min in the control tissues, P less than 0.01). P-450scc activity in adrenal adenomata was 13.4 +/- 2.0 nmol pregnenolone/mg of protein/min, significantly higher than control (P less than 0.05). The present results suggest that increased mitochondrial P-450(11 beta) activities may be characteristic of aldosterone-producing adenomata.

To investigate the feasibility of nanocarbon interconnects for future LSIs, the electrical resistance of exfoliated multilayer graphene (MLG) wirings has been studied with accurate measurements of the number of layers. We employed transmission electron microscopy (TEM) as an exact number determination method, atomic force microscopy (AFM) as a simple method, and an extended optical contrast method as an easy distinction method, which we proposed for determining the number of layers. The sheet resistance of MLG wirings, including TEM determined 3-, 54-, and 341-layer MLGs, has been measured using the four-probe method and the layer number dependence of sheet resistance was discussed on the basis of a ladder circuit model simulation. It is shown that the dependence agrees well with the simulations, suggesting parallel conduction in MLG wirings, even if the probe electrodes are deposited just on the top layer of MLG.

In order to realize a high conductive carbon nanotube (CNT) via structure, an accurate evaluation of electrical properties of CNTs and their metal contacts is essential. We succeeded in evaluating the resistance of CNTs and their contacts individually by using our proposed test method and test structure. The contact resistance of CNTs to metals was dependent on the types of contacting metals, which can be explained by the Gibbs energy of oxide formation and differences in work functions of each metal with CNTs and adhesion property. Ti and Pd had common chemical and mechanical characteristics and showed the lowest contact resistance with CNTs among contact metals we used.

We fabricate planarized carbon nanotube (CNT) via interconnects using chemical mechanical polishing (CMP). The selective growth of CNT bundles in via holes and the filling of spin-on-glass into the space among the CNTs are performed, followed by a CMP process. The via resistance is reduced by post-CMP treatment and post-annealing due to the improvement in the top contact formation. The measured CNT via resistance is higher than the CNT bundle resistance estimated from the measured resistance of an individual CNT. This indicates that contact resistance is higher than the CNT resistance in the CNT via interconnect.

We explored the characteristic behavior of low-temperature graphene growth on catalytic metal films. The results suggested that graphene growth originates from the crystalline facets with specific angles with respect to the crystalline orientation of the catalytic metals at low temperatures, which is different from the conventional growth models. The G/D ratio of the Raman spectrum of the graphene film was affected by both the number of specific facets and the width of the terrace. Because of this behavior, it is important to prepare the surface conditions with a smaller number of facets and a wider terrace for high-quality graphene growth at low temperatures.

We report on the electrical properties of carbon nanotube (CNT) via interconnects with improvement in contact formations between the CNT via and metal electrodes. For the improvement of the bottom contact formation, a TiN/TaN multilayer on a Cu bottom wiring layer is applied to suppress formation of a highly resistive oxide layer on the TaN barrier layer. The top electrode formation with good coverage on CNTs reduces contact resistance. The current–voltage characteristics of ultrafine CNT via interconnects exhibit ohmic behavior. The resistance of the CNT via interconnect is inversely proportional to the via area, indicating that the CNT bundles are grown with uniform quality and density in various-diameter via holes.

We report a synthesis of a closely packed multi-walled carbon nanotube (MWCNT) forest by a multi-step growth method, including a new approach to immobilize catalytic nanoparticles, using plasma-based chemical vapor deposition. The CNT packing density reaches one-half of the theoretical value, where the space of 30–40% is filled with MWCNTs. This value is approximately one order of magnitude larger than that of as-grown CNT forest synthesized using conventional methods. The method is applicable even at a spatially restricted region, for example, in trench or via hole, and is available at the growth temperature as low as 450 °C.

The minor steroid hydroxylase activity of purified bovine adrenocortical mitochondrial P-450 is described. The results indicate that both P-450scc and P-450(11 beta) act on deoxycorticosterone and androstenedione to form 6 beta-hydroxydeoxycorticosterone and 6 beta-hydroxyandrostenedione (6 beta-hydroxylase), respectively. Both forms of P-450 also catalyze 6-desaturation of androstenedione to form 4,6-androstadiene-3,17-dione (6-desaturase).

Carbon nanotubes (CNTs) have been grown by surface-wave plasma-enhanced chemical vapor deposition (CVD) using size-classified Co nanoparticles at low temperatures. A mesh grid is used in the remote plasma-enhanced CVD system for the suppression of ion bombardment damage from plasma. The control of the electric field distribution using a mesh grid with a narrower opening is effective for the CNT growth. Multiwalled CNTs are obtained at a low temperature of 400 °C under low ion-density conditions. No significant difference in the microscopic structure of the CNTs grown at temperatures between 400 and 500 °C is observed.

Carbon nanotube (CNT) growth at temperatures below 400 °C by pulse-excited remote plasma chemical vapor deposition was demonstrated. Reduction of plasma power was carried out in order to decrease the amount of all particles, ions, electrons, and radicals. In addition, a biased plate-type screening electrode was introduced to removal of charged particles, ions, and electrons. The negative bias below 50 V was most effective for growth rate. High-quality CNT growth with the growth rate of 98 nm/min was successfully obtained at 400 °C. The results suggest that both removal of charged particles and control of the amount of radicals are important for high-quality CNT growth at temperatures below 400 °C.

Purified bovine P -450 SCC , the cholesterol side-chain cleaving P -450 in adrenal cortex mitochondria, was found to catalyze a deoxycorticosterone 6β-hydroxylase reaction. A turnover number (moles of product formed/min/mol of P -450) of 12 was found similar to that for cholesterol side chain cleavage activity. Conversion was dose-dependent in terms of P -450 SCC and no reaction took place when any one of the required electron donating components such as NADPH, NADPH-adrenodoxin reductase, or adrenodoxin was omitted. These results confirm and extend earlier observations that 21-hydroxypregnenolone is transformed into both deoxycorticosterone and 6β-hydroxycorticosterone by incubation of adrenal gland slices.

The carbonylation of methane with carbon monoxide in the presence of nitrous oxide produces methyl acetate on a rhodium-doped iron phosphate catalyst under atmospheric pressure and at 573–673 K.