This paper deals with a precision grinding of none-axis-symmetric aspherical surface by use of a resinoid bonded diamond wheel. Ultra-precision grinding system of none-axis-symmetric aspherical surface was developed. In this system, a resinoid bonded diamond wheel was 3-dimentionally controlled with 1nm resolution by linear scale feedback system and scanned on the workpiece surface. At first, the effects of the wheel errors on the workpiece form accuracies and surface roughness were simulated and its compensation methods were discussed. Secondly, the effect of wheel scanning direction on the workpiece surface roughness was researched experimentally. Finally, the none-axis-symmetric aspherical molding dies of a fine grain tungsten carbide were tested with a resinoid bonded diamond wheel to evaluate grinding performance.

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Ultrasonic assisted lapping (USAL) is proposed as a cost-effective alternative to micro-system based technologies, such as lithography, etching, and electron or ion beam micromachining, for manufacturing high surface quality and complex microstructures. The chosen target materials in this research are silicon, glass and advanced ceramics, which are hard-brittle and are not diamond turnable. First this paper describes the principles of USAL for microstructures, followed by obstacles in implementing and using the technique. Then, a path-controlled USAL system with an integrated on-line monitoring AE (Acoustic emission) system is presented. To evaluate the feasibility of the proposed technique, machining experiments were conducted to fabricate linear, spiral and other 2-D arbitrary patterns using a 50μm carbide tool. Further experimental results focus on the achievable surface roughness and observed tool wear as well as on improving the surface roughness by reducing the material removal unit.

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With the proposed Cu-CMP (Chemical Mechanical Polishing) method, laser beam is irradiated into the slurry on the silicon wafer coated with blanket copper layer. Moreover, after the fine particles in slurry are aggregated on the surface of the Cu wafer with optical radiation pressure, the polishing process is implemented. This paper describes about the result of an experiment of laser irradiation into the slurry on the Cu wafer. The phenomenon of SiO_2 particles aggregating with laser irradiation was observed, and conditions to create particle aggregation were investigated. This result indicated that the height of particle aggregation could be controlled by irradiation laser power. Furthermore, the properties of laser aggregation particles on copper layer were also examined. This gives that the aggregated mark closely contacts copper layer.

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The float polishing process is widely recognized for its ability to produce surfaces to atomic conformance, with extremely high flatness. AT-cut, premium-Q, cultured, crystalline-quartz acoustic resonators were fabricated recently by a float polishing process. The study was conducted to maximize the stress-fracture threshold, by optimizing the fabrication process to eliminate sub-surface damage. Polishing medium and removal were examined as variables. The best results obtained, for quartz resonators polished with colloidal silica, are a surface roughness of less than 0.2-nm rms by AFM, and a near-bulk value of pre-fracture flexural strength of 620 MPa. This indicates that float polishing produces a factor of 10 improvement in the strength and the overall quality of quartz over the conventional CeO_2 process.

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GaAs wafers have contributed greatly to improve the performance of light-receiving and light-emitting devices. For such applications, a very low level of roughness, of the order of 0.1 nmRa, is required on GaAs wafers. If a polishing pad is used for a long time, the polishing rate decreases and the roughness on the wafer increases with increase of polishing time. In this study, the surface morphology of the polishing pad was focused as a dominant factor affecting the polishing rate, and, using an image processing technique, a quantitative approach was tried based on an optical microscope image. For the purpose of increasing the lifetime of polishing pads, a further study was made in which the polishing resistance, which correlates strongly with the polishing rate, was monitored.

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Single-crystal germanium is an important infrared optical material for dark-field imaging systems. In the present work, single point diamond turning experiments on single-crystal germanium (100), (110) and (111) planes were conducted in order to examine the ductile machinability. It was found that three kinds of surface textures and chip morphologies were generated during brittle-ductile transition. Ductile machinability exhibits strong crystallographic anisotropy, leading to micro-fractured surface regions distributing in a radial pattern from the workpiece center. Compared to wet cuts, dry cuts were beneficial for ductile machining on specific crystal orientations. However, the minimum critical undeformed chip thicknesses for obtaining homogeneous ductile surfaces on all orientations of the three crystal planes were the same, approximately 60 nm. Under this boundary condition, ductile cut surfaces with nanometric surface roughness can be produced with yielding flow type chips. The findings in this study provide criterions for determining process parameters for the fabrication of aspherical and diffractive infrared optics.

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This paper deals with an experimental study of ultra-precision diamond cutting of magnesium alloys. In order to investigate the cutting performance on the surface integrity and understand the problems on the generation of the good mirror surface in a micro cutting, the experiments on the diamond cutting of magnesium alloys and pure magnesium with an ultra-precision turning machine has been carried out The surface integrity of finished surface of magnesium alloys was mainly examined and discussed the effect of inclusion and intermetallic compound in the micro structure. It was found that the inclusions (Al-Mn compounds) in the work material (AZ31,AZ61) caused to generate the scratches on the finished surface of pure magnesium and AZ91 (cast plate).

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This paper presents distinct element simulation of both conventional and laser assisted machining (LAM) of silicon nitride ceramics. A silicon nitride ceramic material was modeled using bonded particles. The effect of laser heating was translated to the property changes for the ceramic material. It was found that the chip formation process during machining of ceramics begins with cracks that initiate close to the tool tip and propagate into the workpiece. Some of the cracks move upwards to reach the surface to form segmented chips of various sizes. Subsurface damage occurs on the machined part. The damage zone is significantly reduced with laser heating because it promotes shear-induced plastic flow during material removal. Cutting force is much lower in LAM than in conventional machining due to the reduction in material strength with laser heating. The simulation results appear to be consistent with experimental observations in ceramic machining.

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Due to increasing demands for micro- and/or high-precision parts, ultra-micro cutting technologies have been developed at high speed. The importance of atmosphere in micro cutting has been recognized more and more in recent researches. This is because the effects of cutting environments and/or surface oxidation of a workpiece increase when the scale of cutting decreases. In this paper, based on the results of a series of cutting experiments, we discuss how the atmospheric molecules affect the performance of microcutting. The cutting force, critical depth of cut and scratches formed on the workpiece surface have been examined and compared between the results of cutting in air and those in vacuum environments. The workpieces are silicon mono-crystals that have been exposed to air for various lengths of time after being cleaned with RCA method. The experimental results show that brittle/ductile transition takes place with smaller depth of cut in air than in a vacuum. This implies that the brittleness of a silicon mono-crystal decreases in a vacuum. On the other hand, from the comparison of results obtained using a tool moving back and forth in air and in a vacuum, it has also been found that cutting force decreases if atmospheric molecules are sandwiched between a tool and chip during cutting. This could be because of the lubrication effect of the atmospheric molecules.

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This paper deals with a parallel grinding method for ultra-precise aspherical parts such as aspherical lenses, molding dies and mirrors. The parallel grinding method is an arc-envelope grinding method in which a grinding wheel with an arc-shaped cross-section is used to generate an aspherical profile. The aspherical objective lens of the endscope was ground, and form accuracy and roughness of the ground surface utilized the parallel and conventional grinding methods are compared and investigated. Furthermore, the lenses processed by the usual molding and finished by the parallel grinding method were installed in the endscope, and resolving power was compared.

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One of the remarkable achievements of nanotechnology is the ability to achieve nanometre surface finishes in ultra-precision machining of high-precision components for complex optical surfaces. However, the achievement of a super mirror finish in many current industrial applications still relies on the experience and skills of a machine operator through expensive trial and error approach when new materials and new machine tools are used. A better understanding of the surface generation mechanisms is of prime importance for the development of deterministic surface topography model for the prediction of the surface roughness. This paper presents a review of mechanisms of nano-surface generation in ultra-precision machining for various types of materials. Hence, the modelling and simulation of nano-surface generation in ultra-precision machining are discussed.

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Precise and efficient tool setting technique and accurate tool shape monitoring are of essential importance in ultra-precision diamond turning operation. The traditional way of tool setting are typically laborious, inefficient and rely heavily on experience. A big part of the tool setting is done by using a contact probe such as LVDT. The contact tool setting station can normally, depending on the resolution of the probes, place the tool tip to within a 1∿10μm positioning accuracy. However, it is running the risk of damage the delicate tool tip and has the ambiguity introduced by contact point of tool and touch probe. The optical/non-contact way of setting the tool do have the advantage of not having to touch the tool, but its resolution is limited by the optical diffraction limit and the resolution of the CCD device used (mm/pixel). A non-contact precision tool setting system is developed and built in this study using edge-detection image processing and sub-pixel dividing techniques in conjunction with CNC controller of the precision turning machine to improve the system presently available. The results showed that tools of different shapes namely round, half-round and sharp tool could all be positioned to within an error band of ±0.1μm by using the developed tool setting system.

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Ultraprecision optical components require ultrafine smooth surface quality of sub-nanometer or sub-angstrom in Ra. To achieve these requirements, ultraprecision on-machine measuring system is very important, by which the profile measurement and evaluation is conducted on the machine, the form accuracy is improved by the compensating machining when the form accuracy is not enough. So, in this paper, ultraprecision on-machine measuring system with laser-probe was developed for measurement with high-accuracy and high-efficiency. The resolution of the auto focus unit is 1nm, the measuring range is 10mm and the repeatability is 5.6nm. The possibility of the on-machine surface roughness and form measurement with laser-probe was confirmed.

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The combination of single crystal diamond tool and friction-free ultraprecision machining center was employed to turn diffraction Fresnel lens which is composed of micrometer-level pitch and depth of microgrooves. It is found that the technology proposed in the study has a great potential of manufacturing of circular form microgrooves to realize a high dimensional accuracy of diffraction Fresnel lens. According to results of machining experiments, the surface roughness of machined microgroove on diffraction Fresnel lens was approximately 2nm with sharp ridgeline and groove bottom. Especially when the high speed air turbine spindle was applied to ultraprecision turning conducted at 20,000rpm, the dimensional accuracy is less than 0.1μm.

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A new estimating method of the depth of surface affected layers is proposed. In this method, the depth is numerically estimated by vectorizing the digital images of boundary flow in metal structure and carrying out a rotary operations of these vectors. As the results of these operations, the depth of surface affected layers can be estimated quantitatively. It is confirmed that the boundary flow of metal structure can be indicated numerically. These operations take only three minutes and it is clarified that reliable estimation of the depth of surface affected layers can be realized.

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In this study, we observed micro-deformation and its behaviors at the contact region between spherical-tipped diamond indenter and brittle materials by means of a displacementtype (dynamic) micro-hardness tester. The purpose of this study aims finally to establish an assessment way for mechanical properties (elastic modulus, yield stress, hardness, fracture toughness, etc.) of brittle materials by the dynamic micro-hardness tester. In this paper, we investigated and discussed some characteristics of micro-deformation at the contact region with a spherical-tipped diamond indenter for glass materials. As a result, we experimentally found out such tendency that a loading curve would consist of two components; a leaner line and a Herzian curve. This tendency could not be observed in indentation tests using a Vickers indenter. Therefore we concluded that the existence of the linear component should be a particularity only for spherical-tipped indenter. These characteristics of indentation curves would be useful for the micro-deformation analysis of brittle materials in indentation tests with spherical-tipped indenters and the tests enable us to assess mechanical characteristics of the brittle materials.

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Although there are some attempts to produce monocrystalline silicon carbide (SiC) flat surface, the surface properties such as surface roughness don't satisfy the specifications. This study tries to apply helicon sputtering device to Molecular beam epitaxy (MBE) process to improve these properties. This device was used as molecular beam source for generating of Si molecular beam, where the electric field caused by the helicon coil gave energy to the sputtered Si molecules. The amount of the energy was controlled by the electric power applied to the coil. And high purity acetylene gas was used for carbon (C) molecular beam source. Substrate was monocrystalline (111) Si wafer. According to the increase of the electric power, that is, high energy was given to molecules, the roughness of the surface was improved. Auniformly mirror surface of monocrystalline SiC was produced for the entire substrate and the roughness was 1nm (Ra) order.

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A novel method for long focal length measurement is presented, which is accomplished by obtaining the angle of moire fringe formed by Talbot effect of Ronchi grating. When the Ronchi grating was illuminated by spherical wave (plane wave pass through a lens), the period of the Talbot image of the grating, which has a relationship with the radius of the spherical wave (focal length of the lens), will change. When put another Ronchi grating at the place of the Talbot image, moire fringe formed. Correspondingly, the angle of the moire has a relationship with the focal length. So the focal length can be measured by calculating the angle of the moire fringe. The formula of calculating the long focal length from the angle of moire fringe is derived. Error analysis demonstrates that this method can be applied to the real-time testing with high accuracy.

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In this article, we propose a compact absolute length measuring machine (ALMM) with sub-nanometer accuracy and sub-millimeter travel by combining the atomic spacing on the regular crystalline surface and the optical interference fringe, i.e. wavelength. The atomic spacing on the crystalline surface can be obtained with a scanning tunneling microscope (STM). A phase modulation homodyne interferometer (PMHI) can determine displacements between optical interference dark fringes with picometer resolution. The ALMM consists of two piezo-driven sample stages A and B with 1-dimensional motion axes X_A and X_B, atomic force microscope (AFM)/STM heads with tips and YZ scanners, a multi-path PMHI and a thermo-stabilized vacuum cell. A sample of interest and the reference crystal are set on the stage A and B, respectively, which are just beneath AFM and STM heads. 3-dimensional images of the sample and the crystal can be obtained by combining motions of the stages A/B and AFM/STM heads. The stage A and B are independently controlled and their motion axes X_A and X_B are aligned to be parallel with the two arms of the interferometer. The displacement difference between the X_A and X_B axes can be measured and controlled with picometer resolution using the interferometer. Lateral length of the sample along the X_A axis should be measured from the AFM imaging. With the ALMM, an arbitrary scanning length of the stage A, i.e. the sample length, can be determined by utilizing a fine scale (=lattice spacing) and a coarse scale (=wavelength). To asses the possibility of the ALMM, we developed an instrument for direct measurement of lattice spacing on the crystalline surface. In the article, we will discuss the principle of the ALMM and the results of the lattice spacing for graphite crystalline surface.

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In this article, the stabilization technique for the positioning control with atomic resolution of the scanning tunneling microscope tip by referring atomic point and array on regular crystalline surface is discussed. To optimize and improve the performance of the tracking controller against the disturbance, the frequency response of the tracking system is experimentally determined. A controller consists of two control parts is proposed for the stabilization. Each of them is designed for compensating for the low frequency of the thermal deformation and floor vibration, and the high frequency of the acoustic, respectively. A scanning tunneling microscope with two tube type scanners, in which one is for introducing an artificial disturbance and the other is for atomic tracking, is used for experimental determination of the performance test of the proposed controller. The experimental results show that the proposed controller has high stability against the disturbance and can be used to atomic tracking control.

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Error estimation and compensation algorithm for tooth form grinding works of a helical gear is proposed. Tooth profile ground by a formed wheel is modeled by truing parameters and setting parameters of the grinding wheel. Actual tooth form is measured by a touch probe on the machine. The truing and setting parameters are estimated by fitting the modeled surface to the measurement data as the distances between the modeled surface and the measurement points coincide with the probe radius. Error propagation analysis from measurement errors to the estimation errors of the parameters is applied and suggests robust measurement algorithm. The proposed method was applied to the actual grinding process. The truing and setting errors were measured and compensated within 10 micrometers.

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A new optical measuring method of edge profiles with a few nanometer resolution for micro cutting tool is proposed. The edge profiles are scaled by the measurable width between the first two maxima in diffraction patterns, which relate to the width of a slit-type aperture formed between a reference knife-edge and a tool cutting-edge. This technique is applicable for on-machine measurement due to simplicity and long working distance of the optical system. In this paper, first, the theoretical analysis reveals the measurement resolution. Next, the scalability and the practicability of the method are affirmed by the fundamental experiments. Furthermore, the experimental verifications are carried out for practical tools such as straight and helical flute cutting tools. Subsequently, good agreement of profiles measured by developed experimental apparatus with a scanning ion microscope image verifies that the proposed method is efficient to accurately measure cutting-edge profiles.

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Unevenness on a resin liquid surface is one of the factors that precision in the stereolithography decreases. When there is unevenness on a resin liquid surface, it result in uneven thickness, and the forming precision decreases. The conventional stereolithography apparatus are equipped with a leveling device to prevent unevenness on a liquid surface. However, whether the liquid surface is flat, doesn't measure at present. Because of that, it is difficult to make liquid surface to be always flat. This paper proposes a method to measure a uneven liquid surface. An influence on the measurement error of each factor was analyzed. An actual uneven surface shape was measured, and measurement precision was examined. The possibility of the application to Stereolithography was examined from the analysis and the result of the actual measurement. It became clear that the unevenness of 6 microns could be measured with developed equipment.

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This paper reports a new method for detecting defects on the paint panel surface of a car body, which is light scattering method based on optical Fourier transform theory. In this paper, an incident laser beam emitted from He-Ne laser is illuminated onto the test surface. Light reflected from the test surface is directed to a CCD camera through the Fourier transform lens. Then, the scattered light intensity distribution is characterized by the defect size of the test paint surface. The defect size ranges of 5∿50μm in height and 500∿2000μm in width are measurable by computing the intensity ratio of diffuse reflection to specular reflection of panel surfaces. The experiment results show that the proposed method using the laser light is available for detecting defects on the paint panel surface of a car body.

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The conventional defects inspection technology can't apply to an inspection technique of patterned wafers for the next generation semiconductors, because of physical limits imposed by the wavelength of incident beam. So, we attend to particles existing on the patterned wafer that particularly affects the yield and propose new optical detection for evaluating the nano-particles by using evanescent light based on near field optics. In this paper, to verify the feasibility of this proposed method, computer simulation was performed by means of FDTD method based on Maxwell's equations. The results show that the proposed method is effective for detecting particle (100nm in a diameter) on patterned wafer of 100nm lines and spaces.

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The study deals with the improvement of performance of an ultraprecision machining center employing pneumatic bearings and sliders. From the viewpoint that the microvibration greatly affects the surface quality of workpieces, the suppression is tried on the basis of the laminarization of all piping and air bearing surfaces. The ultraprecision machining center is reconstructed to realize the laminarization by calculating the Reynolds number. Cutting experiments were conducted by use of the ultraprecision machining center. As a result, it is found that laminarization is very effective for improvement of surface quality in ultraprecision micromachining.

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This study describes the fabrication and dressing techniques of the micro grinding tools and also highlights on the potentials of these tools with some micro machining test results on hard and brittle materials like silicon and quartz glass. Micro machining test also carried out for stainless steel to test the cutting ability on ductile materials. Cylindrical type micro diamond tools of 100-200μm in diameter have been fabricated by truing using a diamond grinding wheel as truer. Different dressing techniques have been tested to find a suitable one for the fabricated tools. The dressing techniques tested are very simple but quite effective and that made the micro grinding tools ease to apply for machining. Machining test results on quartz glass, silicon and stainless steel have been illustrated with SEM photographs and after that machined surface topography has been analyzed. And an average surface roughness for silicon is about 100 nm, which opens a possibility for machining of hard and brittle materials with good surface quality.

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The present work aims to develop an ultrasonic vibration assisted grinding technology for the internal precision machining of small holes measuring several millimeters in diameter, such as those formed in a fuel injector for an automotive engine. This paper describes a fabricated experimental apparatus, whose main component is an ultrasonic vibration spindle, and experimental investigation of its performance in surface grinding operations. Fundamental experiments are carried out on the fabricated apparatus in order to investigate the effects of the ultrasonic vibration on grinding force and surface roughness. The experimental results indicate that applying ultrasonic vibration to a quill decreases the normal and tangential grinding forces by more than 65% and 70%, respectively, and the surface roughness by as much as 20%.

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The present paper deals with the fabrication of micro flat drills by precision grinding and their application to the drilling into duralumin and stainless steel with out/with ultrasonic vibration on a vertical grinding/drilling machine. It is found from drill fabrication test that using an objective zoom lens with a magnification of 150-800 of a fiber microscope, the diameters range from 18 to 21 μm, and that precision measurement of the diameter after grinding of drill periphery and the precision positioning enabled us to fabricate a flat drill of minimum diameter 10.8 μm. But, web eccentricity must be improved hereafter. From drill life test it is found that, irrespective of the existence of web taper, the drills without back taper showed longer tool life, and that irrespective of back taper, longer drill life were obtained in case of drills with web taper 4/100. This fact suggests that the stiffness at the root of a drill is very important for drill life. In duralumin longer drill life are gained without ultrasonic vibration than with ultrasonic vibration, and in stainless steel vice versa. Burr grows significantly with the increase in number of holes, but roundness of drilled holes is roughly good.

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Miniaturized machine tool can be used to produce 3D features based on CNC and PC-NC technology in the micro/meso scale. Wide applications of CNC technology are developed and there are lots of know-hows in the cutting process and their CNC application. It helps micro/meso scale structure to machine components which can be used directly for practical applications. In the present research, as the machine tool is miniaturized, the manufacturing machine tools costs less when compared to the equipment used in other micromachining technologies. Moreover, with advancement of micro tool technology, the cutting process can be used to produce micro/meso scale parts. In conclusion, the proposed system can reduce the cost by utilizing the current machining technology, and as a result, complex micro/meso parts can be produced efficiently with high productivity.

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Recently, in the field of machine tool, measuring instrument, robot, medical industry, information processing and so on, many minute structures are used for high precision or many functions. In this study, relationships between specification of the sliding surface of a minute part and the coefficient of friction or its standard deviation were investigated in experiment. Photo-fabrication and bonding small steel ball for final treatment on the sliding surface were used. It is concluded from the results that (1) Relationship between specification of the sliding surface on a minute part and the coefficient of friction were declared, (2) Specifications of sliding surface with the desired coefficient of friction were designed by the neural network, and conditions and specifications of sliding surface for the most stable behavior were calculated by this system.

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The paper introduces precise injection molding for miniature products by locally controlling heat flux and magnetic field in the cavity of two small injection molds in each injection cycle. The first 98×98×117mm size mold has small sensors and actuators for controlling temperature/heat flux/pressure/deformation around the cavity of a box shaped product in 30×15×6mm size with 1mm thick walls, and the second 98×98×122mm size mold has a magnetic field generator, a force sensor and a small ring heater for a φ3.5×3.4mm with 0.9mm thick barrel shape product. For example, we could improve the straightness of the box shaped miniature product from 20μm to 3μm.

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Functional surface generation by periodic regular structures such as arrays of dots, lines (short and long) at ultra precision level on hard brittle materials finds applications in optical, electrical and semiconductor applications. This paper reports on development of nano formed surfaces on hard brittle materials. Textured surfaces by periodic structures were fabricated on soda glass, firelite glass and silicon. Specially designed and developed nano indentation tester, knife edged and nano structured diamond indenters were used for the generation of such surfaces. Load-depth analysis on the formed surfaces was carried out. Critical depth, at which ductile to brittle transition in deformation occurs, was assessed for the hard brittle materials. Limit of ductile mode indentation for hard brittle materials was discussed in detail.

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The atomic force microscopy (AFM)-based nano lithographic technique is currently used to directly machine material surfaces and fabricate nano/micro components for MEMS (micro electro mechanical system). As such, three-dimensional molecular dynamic computer simulations were conducted to evaluate the characteristics of the nano lithography process. In this study, the 3-dimensional molecular dynamic (MD) simulations were carried out on monocrystalline copper by varying specific combinations of the crystal orientation and cutting (plowing) direction to investigate their effect on the nature of the deformation.

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This paper describes a design procedure of the linear-motion stage that has silicon monolithic structure and flexure beams suspend the stage. Single crystal silicon is appropriate for the structural material of miniaturized mechanism. However, the anisotropic properties and cleavage should be taken into account at the design stage. In addition, the manufacturing process has strong effects on the final strength because silicon is brittle material and sensitive to the flaw such as chipping. The design consideration is concluded as that the cleavage plane, {111} plane, should be arranged apart from the direction of the tensile stress to compromise both the fracture strength and compliance to achieve accurate motion. Also, the crystal direction <100> should be aligned along the tensile stress to obtain long stroke. The prototypes, size of 30x30mm, were prepared with deep reactive ion etching (DRIE) and its compliance was examined.

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Alternated a-C/a-C : Cr (about 2.5μm thickness) coatings were made by DC magnetron sputtering from graphite and Cr target in an argon discharge. Mechanical and tribological properties were measured by indentation, scratch and pin-on-disc test. The critical scratch load of a-C/a-C : Cr multilayer coatings for total failure is approach 100N. The friction coefficient remains within the range of 0.08-0.1 at loads between 10 and 40N during a pin-on-disc wear test. The wear depth only reaches 0.6μm after a one hour wear test. The surface of a-C/a-C : Cr multilayer coatings undergoes cyclic deformation, and failure eventually occurs as a result of fatigue. The greater compliance and fracture toughness of the a-C/a-C : Cr multilayer coatings allows greater strains or strain energy to be stored before coating failure, and hence significantly improves wear resistance

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Pt/C multilayer film with d-spacing of about 4nm and 30 bilayers has been deposited by the ion beam sputtering process on commercially available 4-inch Si wafer substrates. The x-ray reflectivity of the fabricated film was evaluated using the W-Lα x-ray (λ=0.148nm) with the incident angle 0&acd;2.5 deg. The reflectivity of the first Bragg peak was 58.2%, which was 87.8% of calculated optimum value. The interface roughness of the multilayers derived from the x-ray measurement was 0.229nm rms. High-resolution transmission electron microscope observations and selected area electron diffraction studies indicate that the multilayer consists of amorphous carbon layers and polycrystalline platinum layers. The microscope observation showed the interface roughness of Pt/C multilayers were mainly originated in the size and alignment of the Pt crystallites.

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This paper involves the development of three-dimensional microstructure formation and rapid growth copper electroforming technology in LIGA process. The important contributions involve using multiple power supplies in parallel and air-pressure assistance for the electroforming system to enhance the electroforming rate. The proposed method enhances the allowable applied current density in electroforming. Rapid growth rate is produced in the electroforming process and good deposition material properties are maintained. high cathode efficiency and short plating time were also achieved. The experimental graphs demonstrated these results. The LIGA process involved here to form plastic micromolds for three-dimensional electroforming is also introduced. Graphite film is applied as the x-ray mask membrane, producing successful PMMA exposure at 1mm thick. This proposed electroforming technology has practical applications compared with previous studies on current waveform, electrical potential, agitation method, and electrolyte composition.

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The polymer based photonic or microstructured optical fibers with low-cost manufacturability, and the mechanical and chemical flexibility offer key advantages over conventional silica based photonic crystal fibers. The polymer photonic crystal fiber is fabricated by careful stacking an array of PMMA capillaries to form a preform, and followed by fusing and drawing into fiber on a fiber-drawing tower. The polymer photonic crystal fiber with 2μm &acd; 12μm periodical air holes was successfully fabricated The light (λ=1280nm and 632nm) coupled into this core does indeed travel along long lengths of fiber and remain a single guided mode. The effects of drawing parameters including the temperature and time duration of sintering as well as the drawing temperature and speed on the microstructure of polymer fiber are discussed. The optimum conditions for the fabrication of high quality polymer photonic crystal fibers are also investigated. Keywords : Fabrication, polymer photonic crystal fiber, PMMA, preform

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In this study, we experimentally built a metal-free electro-conductive resin bonded wheel made of carbon as the conductive material to reduce metal ions in grinding fluid and reduction of pollution on the workpiece by metal in the aim to develop LED grinding techniques that are environmentally friendly. At the same time, we also investigated the characteristics of initial electrolytic-dressing characteristics and grinding characteristics. The results showed that the prototyped metal-free electro-conductive resin bonded wheel consisted of a layer of oxides with high oxygen level formed on the wheel surface by the electrolytic dressing. This wheel was also found to have good surface roughness compared to the cast iron bonded wheel generally used for ELID grinding.

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Glass-ceramic aspherical mirrors used as optical elements in space astronomical observatory must be machined with very high profile accuracy and surface smoothness. Precision grinding processes are very effective in fabrication of such profiles. In particular, ELID (Electrolytic In-Process Dressing) grinding method is possible to achieve ultraprecision smooth surface of hard and brittle materials. To obtain ultra smooth surface required by astronomical observatory, final polish process which required long time after conventional grinding process was necessary. ELID grinding method using an ultraprecision grinding machine tool with nano-level hydrostatic guide will be very effective in reducing the time required for finial polishing process. In this paper, a new ELID grinding system is introduced and experimental results of fabricating glass-ceramic paraboloidal mirror are discussed.

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In development of large-scale astronomical telescopes, some new ceramics such as Silicon Carbides (SiC) and glass-ceramics (Zerodur) are applied for primary mirrors. However, the surface finish of the mirrors composed of the ceramics is time-consuming by traditional polishing method. In this study, ELID (Electrolytic In-process Dressing) grinding method, which could achieve high efficiency, was conducted to grind the ceramics for lightweight mirrors (CVD-SiC, Sintered-SiC, Zerodur). The properties of ELID grinding surface were investigated by AFM observation. The results demonstrate that on the ground surface of CVD-SiC and Zerodur, micro voids and micro cracks generated in rough grinding process can be eliminated by #4000 grinding wheel. The total depth of cut required is about 15,, m. Another way, it is difficult to eliminate the micro voids and micro cracks generated on ground surface of Sintered SiC, even under condition of much less depth of cut.

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The design of a mid-infrared high dispersion spectrograph with a resolution of 200000 at 10μm employing Germanium Immersion Grating (GIG) element is required for the 8.2m SUBURA large space telescope. The GIG element with a large number of sharp and smooth micro V-grooves need to be fabricated. Previous study focused on development of micro-grinding process with ELID and its prototype fabrication, developed grinding systems are not applicable to its fabrication because of small machining space and fast wear of small grinding wheel. Therefore, the aim of present research is to develop a new grinding system to fabricate larger GIG and to put the GIG elements to practical use. The authors applied a large ultra-precision mirror surface grinding system and an precision micro-grinding technique, carried out experimental study. This paper described the process principle, grinding equipment and basic grinding experimental results by utilizing metal bonded diamond grinding wheel #4000. The micro-grinding technique combines precision micro-truing and ultra-precision fine grinding. The minimum wheel tip radius of 8.2μm was achieved using the grinding wheel #4000 by the micro-truing process. The corner radius of 15μm&acd;25.8μm of V-grooves was achieved using grinding wheel #4000.

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