We have fabricated Pt/Si-rich oxide (SiOx)/TiN stacked MIM diodes and studied an impact of the structural asymmetry on their resistive switching characteristics. XPS analyses show that a TiON interfacial layer was formed during the SiOx deposition on TiN by RF-sputtering in an Ar + O2 gas mixture. After the fabrication of Pt top electrodes on the SiOx layer, and followed by an electro-forming process, distinct bi-polar type resistive switching was confirmed. For the resistive switching from high to low resistance states so called SET process, there is no need to set the current compliance. Considering higher dielectric constant of TiON than SiOx, the interfacial TiON layer can contribute to regulate the current flow through the diode. The clockwise resistive switching, in which the reduction and oxidation (Red-Ox) reactions can occur near the TiN bottom electrode, shows lower RESET voltages and better switching endurance than the counter-clockwise switching where the Red-Ox reaction can take place near the top Pt electrode. The result implies a good repeatable nature of Red-Ox reactions at the interface between SiOx and TiON/TiN in consideration of relatively high diffusibility of oxygen atoms through Pt.

Our purpose in this study is to develop a scheme to segment the rectus abdominis muscle region in X-ray CT images. We propose a new muscle recognition method based on the shape model. In this method, three steps are included in the segmentation process. The first is to generate a shape model for representing the rectus abdominis muscle. The second is to recognize anatomical feature points corresponding to the origin and insertion of the muscle, and the third is to segment the rectus abdominis muscles using the shape model. We generated the shape model from 20 CT cases and tested the model to recognize the muscle in 10 other CT cases. The average value of the Jaccard similarity coefficient (JSC) between the manually and automatically segmented regions was 0.843. The results suggest the validity of the model-based segmentation for the rectus abdominis muscle.

Grazing incidence X-ray diffraction experiment proved that the a- and c-axes of PMDA-ODA crystals preferentially aligned in normal and parallel directions to rubbing at surface of rubbed film, and that polymer chains of residual amorphous phase aligned in rubbing direction.

The metallic waveguide is one of many effective media for millimeter- and submillimeter-waves because of the advantage of its low-loss nature. This paper describes the fabrication method of PTFE-filled waveguide components with the use of the SR (synchrotron radiation) direct etching process of PTFE, sputter deposition of metal, and electroplating. PTFE is known as a difficult material to process with high precision. However, it has been reported that PTFE microstructures can be fabricated by the direct exposure to SR. First, an iris-coupled waveguide BPF with 5-stage Chebyshev response is designed and fabricated for the Q-band. It is demonstrated that the present process is applicable for the fabrication of the practical components inclusive of narrow patterns. Then, a cruciform 3 dB coupler with air-filled posts is designed and fabricated for the Q-band. Directivity and matched state of the coupler can be realized by “holes” in the dielectric material. The measurement results are also shown.

Depth profile of mass density of vertical alignment film was investigated by X-ray reflectivity, in order to characterize side chains at film surface for vertical alignment of liquid crystals. Existence thin and low density top layer at surface of polyimide film, which was considered to be side chains, was clearly detected. Furthermore, existence of high density layer just below side chain layer was also found, and it is suggested that backbone chain ordering at film surface. Effect of rubbing on VA film was not detected. However, density growth by annealing just below side chain layer of rubbed VA film suggests more ordered backbone chain alignment induced by rubbing.

This paper presents a novel charge transfer CMOS readout circuit for an X-ray time delay and integration (TDI) array with a depth of 64. In this study, a charge transfer readout scheme based on CMOS technology is proposed to sum 64 stages of the TDI signal. In addition, a dead pixel elimination circuit is integrated within a chip, thus resolving the weakness of TDI arrays related to defective pixels. The proposed method is a novel CMOS solution for large depth TDI arrays. Thus, a high signal-to-noise ratio (SNR) can be acquired due to the increased TDI depth. The readout chip was fabricated with a 0.6 µm standard CMOS process for a 15064 CdTe X-ray detector array. The readout circuit was found to effectively increase the charge storage capacity up to 1.6108 electrons, providing an improved SNR by a factor of approximately 8. The measured equivalent noise charge resulting from the readout circuit was 1.68104 electrons, a negligible value compared to the shot noise from the detector.

We developed a new method for characterizing molecular distribution in very thin liquid crystal layer (5-40 nm) evaporated onto rubbed polyimide film used by grazing-incidence X-ray diffraction (GIXD). The diffraction peaks corresponding to intermolecular correlation perpendicular to longitudinal axis of liquid crystal molecule and the clear anisotropic distribution of liquid crystal molecules in a thin layer were successfully observed. We found that in the vicinity of the alignment film, the intermolecular spacing correlation perpendicular to longitudinal axis of the 5CB molecule was expanded by the alignment film, and that the ordering of the 5CB was not so high. As the distance from the alignment film the spacing came close to the intrinsic intermolecular spacing.

We investigated effect of annealing after rubbing by grazing incidence X-ray diffraction, since annealing process is performed in the actual process of liquid crystal display (LCD) fabrication. It was found that rubbed surface polymers were highly crystallized by annealing at 250 after rubbing, and that the crystallization of surface polymers by annealing occurred in the aligned polymer region induced by rubbing. Crystallization of surface polymers by annealing increasingly occurred as increasing of rubbing strength. Thus, it is considered that annealing process after rubbing should also play an important role to control liquid crystal alignment in LCD.

The Transition Edge Sensor (TES)-Energy Dispersive Spectrometer (EDS) is an X-ray detector with high-energy resolution (12.8 eV). The TES can be mounted to a scanning electron microscope (SEM). The TES-EDS is based on a cryogen-free dilution refrigerator. The high-energy resolution enables analysis of the distribution of various elements in samples under low acceleration voltage (typically under 5 keV) by using K-lines of light elements and M lines of heavy elements. For example, the energy of the arsenic L line differs from the magnesium K line by 28 eV. When used to analyze the spore of the Pteris vittata L plant, the TES-EDS clearly reveals a different distribution of As and Mg in the micro region of the plant. The TES-EDS with SEM yields detailed information about the distribution of multi-elements in a sample.

Rubbed polyimide films have been widely used as liquid crystal alignment films for liquid crystal displays. Washing after rubbing is essential to fabricate liquid crystal displays, and should affect alignment of liquid crystal as well as rubbing. We investigated the effects of rubbing condition and soaking in acetone on polyimide films by grazing incidence X-ray diffraction. It was found that soaking in acetone promoted crystallization of surface aligned polymers, and that the crystallization by acetone was dependent on the initial polymer alignment. The larger initial crystalline phase was, the more newly crystallization occurred by soaking. It was also revealed that the crystallization by soaking in acetone was completed within 1 min.

We report effects of washing rubbed polyimide film on the near surface. Especially we focused dependence of solvent. Rubbed polyimide films have been used as liquid crystal alignment films in Liquid crystal displays (LCDs), and in actual LCD panel fabrication washing on film surfaces after rubbing is essential process to remove dust and pollution. We investigated the effects of washing by grazing incidence X-ray diffraction (GIXD) measurements. In GIXD, the X-ray penetration into the polymer was changed from 8 nm (suface sensitive) to 4 nm (bulk sensitive) by variation of the X-ray incidence angle. It was found that crystallization near the surface induced by soaking was considerably dependent on solvent. However, in-plane distribution of the surface polymer chains of polyimide film was not found to be dependent on the solvents.

The surface amino groups of plasma-polymerized films prepared from various nitrogen-containing monomers were quantitatively characterized for bioelectronic and biomedical applications. X-ray photoelectron spectroscopy (XPS) measurements were conducted on two kinds of surfaces: pristine surfaces of plasma-polymerized film prepared using various nitrogen-containing monomers, and theirs surfaces whose amino groups had been derivatized by a primary-amine-selective reagent carrying an XPS label. The XPS data showed that the maximum surface density of amino groups for this film was 8.41013 cm-2. Amino groups constituted 14-64% of all surface nitrogen atoms (NH/N), depending on the monomer used.

PIN diodes for digital X-ray detection as a single photon counting sensor were fabricated on a floating-zone (FZ) n-type (111), high resistivity (5-10 kΩcm) silicon substrates (500 µm thickness). Its electrical properties such as the leakage current and the breakdown voltage were characterized. The size of pixels was 100 µm100 µm. The p+ guard-ring was formed around the active area to reduce the leakage current. After the p+ active area and guard-ring were fabricated by the ion-implantation, the extrinsic-gettering on the wafer backside was performed to reduce the leakage current by n+ ion-implantation. PECVD oxide was deposited as an IMD layer on front side and then, metal lines were formed on both sides of wafers. The leakage current of detectors was significantly reduced with a guard-ring when compared with that without a guard ring. The leakage current showed the strong dependency on the gap distance between the active area and the guard ring. It was possible to achieve the leakage current lower than 0.2 nA/cm2.

An ultra-deep polymer cavity structure exposed using deep X-ray lithography is used as a template for metal electroforming to produce a 24-GHz cavity resonator. The metal cavity is 1.8 mm deep and has impressive structure, including extremely vertical and smooth sidewalls, resulting in low conductor loss. The measured resonator has an unloaded quality factor of above 1800 at a resonant frequency of 23.89 GHz.

Rubbed polyimide films have been widely used as liquid crystal alignment films for liquid crystal displays (LCDs). We investigated the effect of rubbing on the surface molecules of polyimide films by using grazing incidence X-ray diffraction (GIXD) and reflection ellipsometry. We found that rubbing not only caused the polymer chains to align in the direction of rubbing but also to elongate near the film surface. However, the in-plane distribution of surface polymer chains of polyimide film was not found to be dependent on the rubbing conditions.

This paper proposes a design method for representing monochrome medical X-ray images on an electronic display. The required quantizing resolution of the input density and output voltage are theoretically clarified. The proposed method makes it easier to determine the required quantizing resolution which is important in a X-ray diagnostic system.

A normal-distribution-function-shaped superconducting tunnel junction (NDF-STJ) which consists of Nb/Al-AlOx/Al/Nb has been fabricated as an X-ray detector. Current - voltage characteristics were measured at 0.4 K using three kinds of STJs, which have the dispersion parameters σ of 0.25, 0.45 and 0.75. These STJs showed very low subgap leakage current of about 5 nA. By irradiating with 5.9 keV X-rays, we obtained the spectrum of these NDF-STJs. They showed good energy resolution with small magnetic fields of below 3 mT, which is about one-tenth of those for conventional-shaped STJs.

In this study, we propose a robust approach for blind source separation (BSS) by using radial basis function networks (RBFNs) and higher-order statistics (HOS). The RBFN is employed to estimate the inverse of a hypothetical complicated mixing procedure. It transforms the observed signals into high-dimensional space, in which one can simply separate the transformed signals by using a cost function. Recently, Tan et al. proposed a nonlinear BSS method, in which higher-order moments between source signals and observations are matched in the cost function. However, it has a strict restriction that it requires the higher-order statistics of sources to be known. We propose a cost function that consists of higher-order cumulants and the second-order moment of signals to remove the constraint. The proposed approach has the capacity of not only recovering the complicated mixed signals, but also reducing noise from observed signals. Simulation results demonstrate the validity of the proposed approach. Moreover, a result of application to X-ray image separation also shows its practical applicability.

In frequency-domain multiplexing (FDM) for TES signals, a magnetic field summation method utilizing a multi-input SQUID has the fundamental merit of small degradation of the signal-to-noise ratio. We formulated shifts of the operation point due to a common impedance and cross talk currents. These effects are evaluated for several FDM methods, and the requirements for the bandwidth and filters are summarized. The design parameters of multi-input SQUIDs and a flux locked loop driving circuits are also presented.

This paper proposes the design of a physically accurate spine model and its application to estimate three dimensional spine posture from the frontal and lateral views of a human body taken by two conventional video cameras. The accurate spine model proposed here is composed of rigid body parts approximating vertebral bodies and elastic body parts representing intervertebral disks. In the estimation process, we obtain neck and waist positions by fitting the Connected Vertebra Spheres Model to frontal and lateral silhouette images. Then the virtual forces acting on the top and the bottom vertebrae of the accurate spine model are computed based on the obtained neck and waist positions. The accurate model is deformed by the virtual forces, the gravitational force, and the forces of repulsion. The model thus deformed is regarded as the current posture. According to the preliminary experiments based on one real MR image data set of only one subject person, we confirmed that our proposed deformation method estimates the positions of the vertebrae within positional shifts of 3.2 6.8 mm. 3D posture of the spine could be estimated reasonably by applying the estimation method to actual human images taken by video cameras.