In dental treatment with Nd:YAG laser, the laser beam which ordinarily comes out from the optical fiber is effective to eliminate the enamel and the dentin. A diffused and circumferential laser beam, which is produced by using a processed optical fiber at the tip, is effective for the treatment of soft tissue. In the present study, processing characteristics at the tip of the optical fiber is investigated, when TiO₂ powder with average grain size of 1mm is used. An experimental instrument is developed to measure the power and the energy distribution of the straight beam radiated from the processed optical fiber. Furthermore, on the cavity made in the enamel by the straight beam, the volume and maximum depth are measured by a 3D surface profiling system and the surface is observed by SEM.

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This study proposes a novel process of nano–scale patterning method on a metallic glass surface using focused ion beam (FIB) irradiation, followed by wet chemical etching. We found that etch rate of a metallic glass surface irradiated by FIB can be drastically changed, and rapid patterning is possible utilizing this method. Dependences of etch rate of irradiated area on various conditions are investigated. As a result, concave structures can be fabricated at the high dose conditions. The result of the depth dependence on etch time reveals that the affected layer is formed on the interior of the substrate. These results indicate a possibility of these results to novel nano–patterning method of metallic glass.

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It is possible to etch only to the part where the ion beam was irradiated selectively by irradiating the focused ion beam to quartz, and developing it with the buffered hydrogen fluoride afterwards. The etching speed in this case is about two digits earlier than the etching speed by the FIB processing. And, it has been understood to be able to process the nano order. Then, this technique was used, the mask was not used, and the line and the space pattern were made.

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We describe the fabrication of carbon microstructures by laser induced chemical vapor deposition. In this research, ethylene was used as a source gas. Carbon was deposited by argon ion laser irradiation. Plate shaped microstructure fabrication was tried with scanning laser beam irradiation on substrates: SUS304 and absorbent painted glass. As a result, column shaped microstructure was deposited on the SUS304 in spite of scanning laser beam. The mechanism of the column shaped structure deposition was investigated. Laser irradiation with changing irradiation conditions revealed that the difference of the thermal conductivity of the substrates effects for the shape of the deposits. Plates shaped microstructure was fabricated on glass substrate.

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Sphere shaped carbon particles consist of carbon fiber which has a diameter of 20nm to 2000nm, it is called nano–fiber ball (NFB), was synthesized by laser chemical vapor deposition. An Ar ion laser with the wavelength of 514nm was focused on a Ni coated glass plate in a chamber filled with hydrocarbon and sulfur–contained–gas. Those gases were thermally decomposed in the vicinity of laser irradiation spot. Maintaining a laser irradiation formed a NFB at high growth rate. SEM observations of irradiation spot indicated catalytic growth. We discuss about the growth mechanism of NFBs and dependence of catalysis thickness on NFBs growth.

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Laser enhanced wet etching of single crystalline silicon has been investigated. In this report, KOH and NH₄HF₂ has been tested as etchant to discuss possibility of chemical drilling of silicon enhanced by laser beam transmitted through optical fibers. As a result of CW Nd:YAG laser irradiation in KOH, the entire silicon surface including the area out of the laser spot was corroded. H₂O₂ was accordingly added to the solution to realize local selective drilling. Suitable concentration of KOH depends on H₂O₂ concentration, laser power and dopant type. The fact suggests that composition optimization will make the etchant applicable to drilling with optical fibers. In case of NH₄HF₂ laser enhanced etching, the etch rate matched with the rate of KOH and H₂O₂. However, ideas of protecting silica optical fiber from NH₄HF₂ should be necessary for achievement of drilling with fibers because high laser power which must damage plastic optical fiber is required for enough etch rate.

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Color marking in Ti is carried out by YAG laser in the atmosphere. Relations between processing conditions such as the irradiation power, beam diameter, scanning speed and coloring characteristics are obtained. In addition, the marking area is analyzed by AUGER and XPS.

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CO2 laser beam was applied to the cladding of nickel alloy on alloy tool steel by a preplaced powder method. The hardness and microstructure of the clad layer were investigated by changing the power of laser, number of clad layers. The average hardness of the clad layer was 240˜260 HV0.1 under the following conditions:laser power of 2200 W to 3100 W, cladding speed of 400 mm/min, defocusing distance of 30 mm, oscillation width of 7 mm and argon gas shielding. The microstructure of clad layer showed a fine dendeites of which secondary dendrite arm apacing was 5 μm because of their rapid solidification. A heat affected zone was produced near the clad layer on the surface of the alloy tool steel and their martensitic structure was observed.

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We describe modification of various glasses by a CW Laser Backside Irradiation (LBI) method. In this method, an absorbent which was attached on one side of a glass sheet, was irradiated from the other side through the glass with CW laser beam. The characteristics of modified zone were examined by etching in 8 wt.% HF solution. As a result, it turned out that modified zone consisted of two layers and etching rate of the inner part was lower than that of the outer part. The Raman spectroscopy revealed that the density of the inner part increased by the modification.

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When a pulsed Nd:YAG laser is focused into a single crystal silicon and a locally melted region is solidified, internal cracks are developed from the polycrystalline layer to the single crystal layer. This processing is used for dicing of silicon wafer, which is called ″Stealth Dicing″ and attracts attention. In this paper, we conducted thermal–elastoplasticity analysis by Finite Element Method (FEM) in order to evaluate the processing phenomena, and calculated the stress intensity factor of Mode I type for various crack lengths. It was found that the stress intensity factor exceeds the fracture toughness when a crack length is almost the same to the width in the longitudinal section of the polycrystalline layer. Therefore, a possibility of crack propagation was suggested.

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The micro–fluidic devices for blood test are developed. A number of heat–hardening resin–films were piled up on a soda glass. A laser fabricated apart of the channel at each film on every lalmination. The microchannel with then 3–D honeycomb structure and groove structure was fabricated. The artificial capillary vessel sizes have φ13µm and depths of 90µm. In this research processing conditions for artificial capillary vessel were examined. Blood was injected into them. The relation between erythrocyte deformability and the structures of vessel was observed.

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Heating by laser beam and electric discharge energy is applied to material removal process. A tip of electrode is set above a metal target and electric field is applied. The electric discharge is caused by the plasma generation depending on laser heating. In the present experiments, fundamental characteristics of melting and removal in this process are discussed.

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We investigated the light emission from high density plasma produced by pulse laser, which is essential to extreme–ultraviolet (EUV) source for the next generation lithography. We measured EUV intensity and visible light emission from the plasma generated by focused laser to targets of three metals (Sn, Al, Cu) and two target shapes (flat, cone), using a photo diode senser with Si/Zr filter and a high–speed framing camera. The EUV emission from Sn target was highest. The duration of visible light emission from the cone shaped target was longer than that for flat target. These results suggest that the cone shaped Sn target is promising for the high power EUV light source application.

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This paper summarizes some of QED Technologies′ latest developments in the field of high–precision polishing and metrology. Magneto–Rheological Finishing (MRF) is a deterministic sub–aperture polishing process. MRF has demonstrated the ability to produce optical surfaces with accuracies better than 30 nm peak–to–valley (PV) and surface micro–roughness less than 0.5 nm rms on a wide variety of optical glasses, single crystals, and glass–ceramics. The MR fluid forms a polishing tool that is perfectly conformal and therefore can polish a variety of shapes, including flats, spheres, aspheres. QED′s Sub–aperture Stitching Interferometer (SSI) complements MRF by extending the effective aperture, accuracy, resolution, and dynamic range of a phase–shifting interferometer. This workstation performs automated sub–aperture stitching measurements of spheres, flats, and mild aspheres. Aside from the correction of sub–aperture placement errors, our software also accounts for reference–wave error, distortion, and other aberrations. By addressing these matters up front, we avoid limitations encountered in earlier stitching work and significantly boost reproducibility beyond that of the integrated interferometer on its own.

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Atmospheric compensator to reduce the laser measurement error caused by change in the refractive index of air has been produced and applied to the ultra–precision machine tool, and the position measurement error of the machine tool is actually reduced. In this study, the initial length which corresponds to deadpath length in optical path of the laser interferometer is treated to improve the performance of the compensator. The influence of the difference between the set value of initial length and the true one on measurement error is evaluated. The positioning accuracy of the machine tool has been improved by introducing the optimal value of initial length estimated by experimental results to the compensator.

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Laser micro–Raman spectroscopy was used to examine the silicon substrates plunge–cut by a round–nosed diamond tool under various conditions, and the results were compared with those of continuous diamond turning tests described in a previous paper. The results showed that the subsurface layer was partially transformed to amorphous, the extent of amorphization depending strongly on the depth of cut and tool rake angle. The Raman intensity ratio of the amorphous phase to the crystalline phase reaches maximum within the ductile–brittle transition region; while as the depth of cut increases or decreases from the ductile–brittle transition region, the intensity ratio decreases. It was also indicated that although a higher negative tool rake angle can achieve a larger critical depth of cut, it may cause more significant amorphization and subsurface damage than a lower negative rake angle.

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None axis–symmetric aspherical surfaces are required for recent advanced digital devices, such as DVD/CD lenses, fθ lenses and rear projector mirrors in. This paper deals with ultra precision fly cutting of none axis–symmetric aspherical surfaces by single crystal diamond tool. The tool trace in fly cutting of none axis–symmetric aspherical surfaces was introduced and the fly cutting system of 3–axes (X,Z,C) control was developed. In this cutting experiment, electronless Ni was fly–cut and the surface roughness in different radial position was measured. From the experiments, the feed rate control method was useful.

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This report deals with high precision and high efficiency truing of poly–crystalline daimond tools by use of molybdenumalloy.Tungsten carbide can be cut ultra precisely with poly–crystalline diamond micro milling tool,which is installed onto a high speed tool spindle with collet chuck.In this case,the micro milling tool should be trued on the machine.
The poly–crystalline diamond tool has been usually ground with diamond wheel or electric discharge machining.But the traing preciseness with conventional methods was not so high and the truing of poly–crystalline diamond tools by molybdenum alloy is proposed and basic reserch was carried out with comparisons of GC,stainless steel.

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The moulding dies are usually made of electroless nickel to be cut precisely with single crystal diamond tool. Recently, hard materials such as hardened steels or WC have to be cut for more moulding times. In this study, a new micro milling tool of PCD was developed and basic cutting characteristics were researched in milling of WC. And a feasibility study of a precision aspherical cutting was carried out. From the experimental results, mirror surface of 6.5 nmRz and form accuracy of 0.09μmP–V were obtained. It is clarified that precision cutting of WC dies can be done with the developed PCD milling tool.

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This paper presents a new aspheric generator and high–precision measuring and compensation method for next–generation DVD lens mold. It reports on composition of new aspheric generator, on the on–machine measuring system. It is confirmed that the small radius lens mold for next generation DVD is machined by using this machine and on–machine measuring system with 40 nm accuracy.

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[in Japanese]

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[in Japanese]

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Three–Dimensional Internal Structure Microscopes (3D–ISM), developed by authors, have enabled us to observe internal structures of biological specimens by cutting cross–sections with rotating knives. A number of different biological specimens were successfully observed, however, 3D–ISM are effective only for soft tissues due to its cutting mechanism, flat and thin rotating knives. In this report, we used a new cutting mechanism, a single crystalline diamond fly–cutting tool on a high precision cutting machine, and measured bone cutting force. We developed a special device based on a milling machine for this method and obtained mirror–like cross–sections of biological specimens containing hard tissues like bone, and also observed clear images of microscopic internal structures of hard tissues.

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Our laboratory have been developed the Ultra–Precision Lathe for Lens Dies without Polishing. We tried ductile–mode cutting to Si wafer and optical glass (BK7) using this lathe, and observed processed area by Confocal Scanning Laser Microscope with a Raman Spectroscopy Interface. By obtained Raman spectra, amorphous layer were found from ductile–mode cutting area of silicon, and different spectra were observed from the ductile–mode cutting area and brittle–mode cutting area of glass.

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A 4–axis machine tool is developed to fabricate micro patterns on glass cylindrical parts. Glass can be machined without brittle fracture in the milling processes with ball end mills. Some machining examples verify the machine tool with the presented approach.

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Parametric machining is discussed to make texturing patterns on surfaces. Machining principle is shown with the developed machine tool with the simultaneous control of two rotations. Some examples are shown to verify the presented machining approach.

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Metrology plays an important role in surface figuring with subnanometer accuracy. We have developed RADSI (relative angle determinable stitching interferometry) for the surface figuring of elliptical mirror for hard x–ray nanofocusing. On the mirror surfaces figure accuracy of a few nanometers is necessary. In the measurement using the Fizeau interferometer, the density of the interference fringes on the X–ray mirror surface is so high that the entire area of surface profile cannot be acquired at once. The conventional stitching method using a common area between neighboring shots generates stitching errors larger than the figure accuracy of nanofocusing mirror. In the RADSI, stitching angles are determined not by the conventional method, but by the new method using the mirror′s tilt angles measured at times when profile data are acquired. Using the RADSI, the high measurement accuracy of approximately 3 nm peak–to–valley was achieved in the measurement of the elliptical mirror. We have carried out line focusing tests of the fabricated elliptical mirror at the 1–km–beamline in SPring–8. The line focus profile with a 40 nm full width at half maximum (FWHM) was realized.

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[in Japanese]

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The quality of gears is classified according to deviations by ISO 1328, and recently a system to evaluate gear measuring instruments is to be established. The purpose of our research is to develope a highly accurate gear measuring instrument with small uncertainty of measured values and a repeatability less than 1 micro meter.
To reduce the transmission errors caused by the mechanisms in conventional gear measuring instruments, a gear measuring instrument consisting of two direct drive axes, linear axis and rotary axis, is proposed and being developed by authors.
The basic concept and configuration of the measuring instrument are described in this paper.

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The purpose of our research is to develope a highly accurate gear measuring instrument with small uncertainty of measured values and a repeatability less than 1 micro meter.
And a gear measuring instrument consisting of direct drive linear axis and rotary axis is being developed by authors.
In this paper, the experimental results of motion control of each axis and synchronous driving of two axes to simulate profile measurement are given.

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The form of machine part with axis, e.g. gear, has much influence on its performance, therefore strict quality control of machine part with axis is demanded. Atomic force probe measuring machine can achieve more accurate measurement than current coordinate measuring machine. But appropriate measuring method is needed to apply it to the measurement of machine parts, especially machine parts with axis, because their form error must be evaluated in reference to the position of the axis. In this report, precise measuring method of machine parts with axis by an atomic force probe measuring machine is proposed. In addition, influence of error factors of this measurement is investigated.

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This paper desribes a PZT–based fast–tool–control (FTC) system for ultra–precision diamond turning. A pre–loaded ring–type PZT with a maximum stroke of 70 mm is employed to actuate the diamond tool attached on the free end of the PZT. The displacement of the PZT is servo controlled by a PID controller based on the measurement result of a capacitance–type displacement sensor integrated inside the PZT actuator. A piezoelectric–type force sensor is coaxially connected on the other end of the PZT for detection of machining force. Investigation of static and dynamic responses of the FTC, calibration of the force sensor output are carried out.

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A method realizing high accuracy even in the measurement scene for coordinate measuring technology have been investigated. In this report, we clarify the factor of the probing error that was observed in the measurement scene.

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Making sure of relationship between probing points and uncertainty, multi measurement strategies are used. It is one of the techniques for evaluation of the uncertainty of measurement. Workpiece having bad form error, say 40μm, is measured. On circle measurements, probing points are varied from 5 to 12. Error from strategy varies from 8 to1μm. This variation of error derived from the number of probing point is compared to the simulation, and they come to an agreement

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In order to achieve the further improvements to speed and accuracy of NC machine tools, a variety of devices for measuring the motion accuracy have been developed. But the existing methods, for example DBB method (Double Ball Bar method) etc., are the measuring method for only circular motion and difficult to measure along arbitrary tool path in a three dimensional space. We developed the measuring method using links and rotary encoders and have improved it. And this time, we aimed the expansion of measuring range applying the counter weight. The repeatability of the measurements has also been investigated.

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Precision rotary/linear dual–axis positioning systems with nanometric resolution, high–speed and wide moving stroke are also desired in various areas of nanotechnology, such as nano–manipulation of cells, micro–parts, etc. This paper presents prototype rotary/linear dual–axis positioning system in which a rotor (moving body) can be moved along and rotated about the axis (Z) of a ceramic cylinder (driving rod). The stroke of the prototype system along Z–axis, which is limited by the length of the cylinder, is designed to be 10 mm and there is no limitation in the rotary motion. Experimental results indicate that the maximum speeds in the two directions are approximately 2.4mm/sec and 50rpm, respectively.

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We have made a regular crystalline ruler using a regular crystalline surface and a scanning tunneling microscope. In the autumn meeting of JSPE 2004, we proposed 2–dimensional encoder method by combining multi–probe scanning tunneling microscopes and regular crystalline surface. In the report, we show the experimental verification of 2–dimensional encoder using the prototype equipment and the dither vibration method.

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We have developed a length measurement method by combining a phase modulation homodyne interferometer, whose resolution is picometer or less when the optical path difference equals wavelength x integer, and regular crystalline surface, whose lattice spacing can be observed with a scanning tunneling microscope (STM). In the method, optical fringe of the ineterferometer and the lattice spacing derived from STM observation, are utilized as coarse and fine scales, respectively. We made the prototype equipment and demonstrate its performance to evaluate nonlinear interpolation error of a optical linear encoder, whose resolution is less than subnanometer.

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Planar linear motor is a precision positioning stage, which is different from the usual XY stage and consisted of multiple linear motors arranged orthogonally in the same layer. It is a general way to employ a laser interferometer as the positional sensor of the plane linear motor. Therefore, it is necessary to use an external interferometer and orthogonal gauge in higher accuracy for accuracy evaluation and calibration. In this paper, mixed 2–point method is proposed to let user perform calibration easily and relative high accuracy and the primary measurement result of reflecting mirror profile is reported.

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This paper describes a surface encoder, which consists of a sensor unit and a sinusoidal grid, for precision positioning of a sawyer motor–driven stage over a long stroke. The 2D local slopes of two points on the grid surface are simultaneously detected by the two angle sensors of the sensor unit. The positions and directions of movement in the X– and Y–directions can thus be detected by the two–phase sensor outputs with a phase difference of 90 degrees in each direction. To generate quadrature encoder outputs, the collimated light from the laser diode of the sensor unit is passed through an aperture plate on which two apertures are generated in such a way that the two beams output from the apertures are exactly projected onto the desired positions on the grid surface.

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An laser interferometer has been developed in order to measure straightness by use of the three surface method. The purpose of this development was reducing uncertainty of straightness measurement. This paper presents an test result of this inrerferometer.By use of this interferometer and the three surface method, we measeured shapes of three 400 mm steel straight edges. The measurment was repeated 20 times. As a result, standard deviations of measured shapes were less than 10 nm (k=1) in all samples.

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We proposed a novel SOI wafer inspection technique for nano–defects in the layers of SOI wafer surface, not by using scattered light but evanescent light based on near–field optics. In this method, we treat the air on wafer and SOI layer and BOX layer as the 3 layers dielectric slab waveguide for IR laser light that generates IR evanescent wave onto the near field region over wafer surface. By using probe to scan the evanescent light that is easily disturbed by nano–defects existing on the wafer surface or in the layers, this method makes it possible to sensitively detect the nano–defects, even if they exist in the thin layers. In this paper, first the near–field of the wafer surface vicinity is analyzed by using FDTD (Finite Difference Time Domain) simulation tool. These simulation results showed this method can detect and classify the nano–meter scale defects on the surface and in the layers of SOI wafers sensitively. Next the several fundamental experiments for SOI wafer with the layer thickness of 160nm were carried out to verify the results of this computer simulation.

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In our reseach, an optically trapped silica particle is used as a measuring probe particle. The probe particle is trapped at a beam waist of the focused laser light and is forced to vibrate by deflecting the beam waist using AOD. The vibrating probe particle has a resonance frequency because it is governed by the spring–mass–damper system. When an aerosol particle is attached to the probe particle, the resonance frequency shifts according to the increase of the total mass. The mass of the aerosol particle can be measured from the shift of the resonance frequency.

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A super–resolution microscopy technique with standing evanescent light in TIR (Total Internal Reflection) has been proposed that resolves samples on the interface in a lateral resolution of better than the diffraction limit. Samples are illuminated with standing evanescent light shifted in different positions, and the sample distribution is calculated from acquired scattering images in the use of ART (Algebraic Reconstruction Technique). This technique improves the lateral resolution up to about 1/7 of the diffraction limit.

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The introduction of nano–voids into low–k dielectric layers is very effective in reducing the dielectric constant, but the killer–pore is a crucial defect on further integrations and miniaturizations, which remains a problem that does not seem to have a solution. Destructive analytical techniques such as the scanning transmission electron microscopy are mainly used for the inspection of low–k dielectric layers, but non–destructive inspection is required. We proposed non–destructive inspecting method of the nano–void in the low–k dielectric layers based on the near field optics. We tried electromagnetic simulations, and demonstrated the effectiveness of the proposal technique.

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Indenter geometry is obtained as numerical data of 3D images with some kind of instruments, such as scanning white light interferometry, AFM, etc. In order to analyze geometric parameters, i. e., angles between opposite faces, angles of square perpendicular to the indenter axis, length of line of conjunction, etc. in good accuracy, the procedure based on a model expressed with regression planes of indenter surfaces was developed. The advantage of proposed method was examined by comparing with the conventional method, which measures the geometry of cross sections of 3D images.

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Micro channel was fabrication by laser in a laminate film on a glass substrate, and produced the micro channel for a blood test. The sandglass type channel was fabricated using this method. Moreover, this channel succeeded in flowing the blood to the center of channel, by flowed a physiological salt solution in both sides of the blood. Then the blood and the solutions were flowed by a free falls by gravity like a sandglass. In this type, the flow width of the blood was about 30 μm and not good for the blood test, because blood corpuscles were overlaps. In this report, we measured convergence of flow widths of blood with a changing the length of blood and physiological salt solution reservoirs from the confluence point and their volume.

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In the liquid crystal panel manufacturing process, the removal technique of the foreign materials which adheres to the glass panel surface for the quality controll is required. As a method of being balancing in the fundamentality removal ability and the flexibility to the glass panel which enlargement accelerates these days, the roll wheel system which is proven method in the printed circuit board polishing was adopted. Tool structure was examined in detail and optimized also including removal conditions. Consequently, it checked that only a foreign materials was removable, without generating a scratch on a glass panel.

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This paper describes the detection error mechanism of the dosimeter for the high frequency electromagnetism noise generated with PHS. PHS used in Japan is specified as the frequency of 1.9GHz, the output energy of less 10dbm. Since the dosimeter is given the PHS noise energy of –5.6dbm, the dosimeters have occurred the detection error.

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This paper describes shielding effect of the high frequency noise by PHS using the simulation (HFSS). When the case of the dosimeter is perfectly the sealing condition, the shielding effect is under 1/1000. Therefore, the shielding effect is reduced in 1/10, when gaps are 50 μm. The reduction of the shielding effect by the gap is larger.

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