Yuichi Haruyama

Characterization of Hard Diamond-Like Carbon Films Formed by Ar Gas Cluster Ion Beam-Assisted Fullerene Deposition

The coordination of carbon atoms in diamond-like carbon (DLC) thin films formed by Ar gas cluster ion beam (GCIB) assisted deposition using fullerene as the carbon source was investigated by measuring near-edge X-ray absorption fine structure (NEXAFS) spectra of the carbon K-edge over the excitation energy range 275–320 eV, using synchrotron radiation. With attention to the peak corresponding to the transition of the excitation electron from a carbon 1s orbital to a π* orbital, relative sp2 contents of various DLC films were estimated. The sp2 contents of the DLC films formed by the GCIB-assisted deposition were observed to be lower than those of the DLC films formed by other methods. The hardness value measured with a nano-indentation technique was found to be strongly related to the sp2 content of the DLC film.

Nozzle-nanostructure fabrication on glass capillary by focused-ion-beam chemical vapor deposition and etching

Three-dimensional nanostructures on a glass capillary have a number of useful applications such as manipulators and sensors in the various microstructures. This time, we have demonstrated the fabrication of a nozzle nanostructure on a glass capillary for a bio injector by 30 keV Ga+ focused-ion-beam assisted deposition with a precursor of phenanthrene vapor and etching. It has been demonstrated that nozzle nanostructures with various shapes and sizes have been successfully fabricated. An inner tip diameter of 30 nm on a glass capillary and a tip shape with an inclined angle have been realized.

Optical measurement and fabrication from a Morpho-butterfly-scale quasistructure by focused ion beam chemical vapor deposition

The Morpho-butterfly wing reflects interfered brilliant blue, which originates from nanostructures on its scales, for any incidence angle of white light. We have fabricated a Morpho-butterfly-scale quasistructure using focused ion beam chemical vapor deposition and observed brilliant blue reflection from this quasistructure with an optical microscope. We measured the reflection from real Morpho-butterfly scales and from the quasistructure with a photonic multichannel spectral analyzer system. The reflection spectra of the quasistructure were very similar to those of Morpho-butterfly scales.

Three-Dimensional Nanoimprint Mold Fabrication by Focused-Ion-Beam Chemical Vapor Deposition

Three-dimensional diamond-like carbon (DLC) mold fabricated by focused-ion-beam chemical vapor deposition (FIB-CVD) using a precursor of phenanthrene has been applied to a nanoimprint process. Various 3D nanostructure DLC molds have been delineated by FIB-CVD using a computer-controlled pattern generator which is a commercially available pattern generator for electron beam lithography. Then, the molds were imprinted into hydrogen silsequioxane (HSQ) as a material replicated at room temperature. It was confirmed that the 3D mold, after nanoimprint lithography (NIL), kept its original shape, and 3D mold structures were successfully imprinted into HSQ. These results reveal that the 3D mold fabricated by FIB-CVD can be applied to NIL.

Performance of nanomanipulator fabricated on glass capillary by focused-ion-beam chemical vapor depositiona)

An electrostatic 3D nanomanipulator that can perform inclusion of nano parts and cell operation has been developed by focused-ion-beam chemical vapor deposition (FIB-CVD). This 3D nanomanipulator has 4 fingers in order to catch the target of various shapes firmly. The movable principle is that an electric charge is accumulated in the structure by applying voltage to 4 fingers structure and it moves by repulsion of the electric charge. Furthermore, we succeeded to catch the microsphere (polystyrene latex with a diameter of 1μm) by using this 3D nanomanipulator with 4 fingers.

Nanomechanical switch fabrication by focused-ion-beam chemical vapor deposition

Focused-ion-beam chemical vapor deposition (FIB-CVD) is an excellent technology to form three-dimensional nanostructures. Various three-dimensional nanostructures such as an inductance, a capacitor, a resistance, and a filter-circuit have been demonstrated by applying FIB-CVD with phenanthrene (C14H10) source gas using a computer-controlled pattern generator (CPG). The electrical resistivity measurement of the free-space-nanowiring was carried out by two terminal electrode method. The resistivity was 1×102Ωcm in the case of using C14H10. To reduce the electrical resistivity, tungsten hexacarbonyl [W(CO)6] is added to C14H10 as a source gas. Increasing content of W(CO)6, the electrical resistivity becomes lower from 1×102to2×10−2Ωcm at room temperature. By using free-space-nanowiring fabrication technology, the world smallest nanomechanical switch composed of a coil and a nanowiring has been fabricated and confirmed the switching operation by applying a voltage.

Surface modification of fluorocarbon polymers by synchrotron radiation

Fluorocarbon polymers are fluorishingly used as the material for industry from some characteristic advantages - chemical stability, thermal stability, excellent electric property and so on. One of other characteristics of fluorocarbon polymers was hydrophobicity of these surfaces, and fluorocarbon polymers were applicable to various industrial yields by taking advantage of this characteristic. However, in the several yields, such as painting and adhesion, this hydrophobicity has restricted the application of fluorocarbon polymers. In the present study, wettability on the surface of polytetrafluoroethylene (PTFE) chip was modified by exposure to synchrotron radiation (SR). This is the first report on SIR exposure effects about wettability of PTFE.

Mechanical characteristics and applications of diamondlike-carbon cantilevers fabricated by focused-ion-beam chemical vapor deposition

Diamondlike-carbon (DLC) cantilevers were fabricated with a commercially available focused-ion-beam chemical-vapor-deposition (FIB-CVD) system using a beam of 30keV Ga+ ions, and the mechanical characteristics of the cantilevers were measured. Vibration frequency of the cantilevers was passively measured using scanning electron microscopy. Resonant frequency of DLC cantilevers fabricated at 0.1–0.5pA beam current was found to be constant. The equivalent spring constant of the cantilevers was identified by squeezing the tip of a Si3N4 cantilever and a DLC cantilever together. Using the measured displacement, the spring constant of the DLC cantilever was calculated as (1.1±0.2)×10−2N∕m. Furthermore, Young’s modulus and the density of the DLC cantilevers were measured to be 187±32GPa and (3.8±0.7)×103kg∕m3, respectively. The DLC cantilevers were used as mass sensors in an ultrasensitive sensing application. A small amount of DLC was deposited on the tip of a DLC cantilever as a mass adhesion by FIB-CVD at 0....

Characteristics of Nano-Electrostatic Actuator Fabricated by Focused Ion Beam Chemical Vapor Deposition

The three-dimensional (3D) nanostructure fabrication technology using focused ion beam chemical vapor deposition (FIB-CVD) is very effective for highly efficient 3D nanomechanical device fabrication. We can fabricate 3D nanostructure easily and freely with this fabrication technology using FIB-CVD. Here, we demonstrate the fabrication of various 3-D nano-electrostatic actuators and manipulators on a glass capillary by 30 keV Ga+ focused-ion-beam-assisted deposition with phenanthrene vapor as a precursor, and the operation of these actuators and manipulators by applying voltage onto a Au-coated glass capillary under an optical microscope is shown. Furthermore, the structural characteristics and functionalities of them are described in this paper.

X-Ray Photoelectron Spectroscopy Study of Synchrotron Radiation Irradiation of a Polytetrafluoroethylene Surface.

The effect of synchrotron radiation (SR) irradiation of a polytetrafluoroethylene (PTFE) surface was investigated using X-ray photoelectron spectroscopy (XPS). After the SR irradiation, the relative intensity of the F 1s peak to the C 1s peak decreased markedly. The chemical composition ratio of the F atoms to C atoms was estimated to be 0.29. From the curve fitting analysis of C 1s and F 1s XPS spectra, the chemical components and their intensity ratio were determined. The reason for the chemical composition change by the SR irradiation was discussed.