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We propose a magnetic separation system using superconducting bulk magnets to effectively separate organic dyes in wastewater. Two key technologies are applied in this system: magnetic seeding and magnetic separation. Magnetic activated carbons (MACs) are used to adsorb organic dyes Orange II and Crystal violet, which serve as magnetic seeds. We set up a magnetic separator by placing an acrylic pipe between the magnetic poles of a face-to-face superconducting bulk magnet for high gradient magnetic separation (HGMS) with the use of a stainless steel filter, composed of ferromagnetic wire stuffed into acrylic pipe. The experimental results show that the adsorption ratios of 99% and the separation ratios of over 97% were achieved at low flow rate for the organic dyes.

We investigated the effect of ultrahigh-resolution salty (NaCl contained) development of hydrogen silsesquioxane (HSQ) resist on forming fine dot arrays with a pitch of 15×15 nm2 by 30-keV electron beam lithography for patterned media. The optimized concentration of resist developers was determined to fabricate most packed pattern. We found that increasing the concentration of NaCl into tetramethyl ammonium hydroxide (TMAH) could greatly improve the resist contrast (γ-value) of HSQ. And by using 2.3 wt% TMAH/4 wt% NaCl developer, we demonstrated 15×15 nm2 pitched (3 Tbit/in.2) HSQ resist dot arrays with a dot size of < 10 nm.

We have studied the possibility to form fine magnetic column arrays using 30-keV-electron beam (EB) drawing with thin calixarene resist and 200-eV-Ar ion milling, and nanometer-sizing effect of the magnetic column on the corecive force for patterned media. We achieved 20-nm-sized resist dot arrays on PtCo magnetic and thin metals layers on glass substrate. We formed fine magnetic column arrays with a diameter of 39 to 106 nm and a space of about 100 nm using the resist pattern by the 200-eV Ar ion-milling. Using the nano magnetic column arrays, the hysteresis were measured by X-ray magnetic circular dichroism (XMCD) with an energy of 11.57 keV, which corresponds to an energy edge of Pt-L3. It is clarified that a coercive force of the nanometer-sized magnetic column increased as the diameter decreased.

The influence of the phase-change materials on the performance of memory devices for low power consumption and multi-level storage was investigated in this work. Doping N into chalcogenide phase-change materials resulted in higher resistivity and low-response to the temperature. The former characteristic leaded to high heating efficiency for phase change via self-heating and thus reduced the power consumption to about 1/20. The latter characteristic enabled easy control of phase change process in the memory device for multi-level storage. 16 distinct resistance levels were demonstrated in our lateral device by adopting a top heater structure

In this work, we investigate the effect of the N-doping on microstructure and electrical properties of chalcogenide Ge2Sb2Te5(GST) films for application to multilevel-storage phase change memory (PCM). Crystal size can be markedly reduced from 16 nm to 5 nm by N-doping into GST. The crystal growth suppression is believed to be controlled by distributed fine nitride particles. The resistivity of N-GST as a function of annealing temperature exhibits a gradual change due to the crystal growth suppression. The characteristics imply that N-GST is suitable for application to multilevel-storage PCM as the next-generation nonvolatile memory.

We have studied a step-in mode non-contact atomic force microscopy (NC-AFM) for precise measurement of fine and steep structure with nanometer resolution in air. When a high aspect structure is measured using step-in mode AFM with the sharpened and slim probe, it is required that AFM control has to be performed at a force of

We have investigated random-access multilevel storage in phase change memory by staircase-like pulse programming. Staircase-like pulse consists of first sub-pulse and second sub-pulse. Our simulation exhibited that any resistance levels are expected to be randomly accessed by controlling the crystallization with different widths of second sub-pulset2. Based on the simulation results, we did experiment on staircase-like pulse programming. Experimental results showed that the device resistance gradually increased with reducing second sub-pulset2to 0 ns. In other words, random access to any resistance levels was demonstrated to be possible simply by changingt2.

In this work, we studied the fabrication of 12-nm-size nanodot pattern by self-assembly technique using high-etching-selectivity poly (styrene)-poly (dimethyl-siloxane) (PS-PDMS) block copolymers. The necessary etching duration for removing the very thin top PDMS layer is unexpectedly longer when the used molecular weight of PS-PDMS is 13.5-4.0 kg/mol (17.5 kg/mol total molecular weight) than that of 30.0-7.5 kg/mol (37.5 kg/mol total molecular weight). From this experimental result, it was clear that PS-PDMS with lower molecular weight forms thicker PDMS layer on the air/polymer interface of PS-PDMS film after microphase separation process. The 22-nm pitch of nanodot pattern by self-assembly holds the promise for the low-cost and high-throughput fabrication of 1.3 Tbit/inch2storage device. Nanodot size of 12 nm also further enhances the quantum-dot effect in quantum-dot solar cell.

Performance of lateral phase change memories (LPCMs) is investigated by both electrical characterization and finite element analysis. Ge2Sb2Te5 lateral PCMs (GST-LPCMs) exhibit a low reset current but a bad endurance. By replacing GST with Sb2Te3 (ST) and adding a TiN layer between ST and electrodes, the ST-TiN-LPCMs are demonstrated to have a much improved endurance. Finite element analysis of the LPCMs with electric-thermal structural interaction shows that thermal confinement makes GST-LPCMs low-power consumptive but that high level stress makes them readily broken. In contrast, ST-TiN-LPCMs experience low level stress during operation but high power consumption is required.

We have studied functionalization of guide pattern with brush treatment. Especially, the effect of brush treatment on ordering of nanodots formed on the guide pattern was investigated. We used polydimethylsiloxane (PDMS) as brush modification to form self-assembled nanodots on the guide pattern using polystyrene (PS) - PDMS as block copolymer. The brush treatment using toluene solvent made guide patterns of the electron beam (EB) drawn resist behave like PDMS guide patterns and good ordering of the nanodots has been achieved. It was demonstrated that the brush treatment enabled the PDMS nanodots to be regularly located in the desired positions defined by the EB drawn guide patterns.

We have studied on theoretical electron energy deposition in thin resist layer on Si substrate for electron beam lithography. We made Monte Carlo simulation to calculate the energy distribution and to consider formation of nanometer sized pattern regarding electron energy, resist thickness and resist type. The energy distribution in 100 nm-thick resist on Si substrate were calculated for small pattern. The calculations show that 4 nm-wide pattern will be formed when resist thickness is less than 30 nm. Furthermore, a negative resist is more suitable than positive resist by the estimation of a shape of the energy distribution.

We studied long-range ordering of self-assembled nanodot arrays for patterned media, using a guide post and line mixing template made of an electron beam (EB) resist to pack many nanodot arrays between guide lines. We designed the mixing pattern, EB-drew it on silicon substrate, brushed the surface of the pattern, and self-assembled block copolymer dot arrays using polystyrene-polydimethl siloxane (PS-PDMS) and mixing templates made of hydrogen silsesquioxane (HSQ) negative EB resist. The experimental results demonstrate the possibility of forming long-range ordering of 6 and 9 self-assembled nanodot arrays with a size of 20nm and a pitch of 33nm between the guide lines, using the mixing templates with three and fourfold post lattices, respectively.

We have investigated step-in mode non-contact atomic force microscopy (NC-AFM) for precise measurement of fine and steep structures having high aspect ratios. We have proposed piconewton controlled step-in mode AFM using NC-AFM to suppress bending and slipping of the probe on a slope. We have constructed a prototype of the step-in mode NC-AFM using a quadrature frequency demodulator for detecting the resonant frequency shift of the cantilever. Experiments revealed that the system was able to perform step-in mode NC-AFM even in air. We obtained a faithful AFM image of the steep structure of a dry-etched Si pattern without bending or slipping of the probe at approximately 2-3 pN using a sharp, slim probe, as compared with a step-in mode contact AFM image obtained at 1, 5, and 10 nN. [DOI: 10.1380/ejssnt.2011.122]

In recently, mesh nozzle nebulizer was caused problems of such as nebulizer disorder(Liquid leaking, not in spray). This work used various kinds of metallic nozzles for neburizer. Several liquid, such as skin lotion and solution for cleaning air, were sprayed by these nebulizers. The elution of metals in sprayed solution was analyzed. We show the obtained results with some elucidations.

Lateral rectangular (R-) and step-like (S-) channel phase-change memory (PCM) cell structures are numerically analyzed for multi-state storage based on their temperature distributions and their programming characteristics. The S-PCM cell is characterized by the sequentially melted sub-channel and step-like programming characteristics. From the viewpoint of the performance for multi-state storage, the step-like characteristics indicate high controllability for its application of multi-state storage.

In this study, we investigate self-assembled large-area nanodot fabrication on a silicon substrate using poly(styrene)-poly(dimethyl-siloxane) (PS-PDMS) for the application to quantum dot solar cell. By optimizing the PS-PDMS concentration by 2% and the volume of PS-PDMS solutions by 20 μL/cm2 dropped to silicon substrate, nanodots with a pitch size of 33 nm and a diameter of 23 nm are achieved with the molecular weight of 30,000-7,500. It is found that the dropped volume of PS-PDMS solution correlated to the thickness of spin-coated PS-PDMS layer has a great effect on the size and the pattern morphology.

In this paper, we report two kinds of guide patterns precisely created by electron beam drawing. These guide patterns are expected to precisely control the arrangement of nanodots self-assembled from block copolymer (BCP) in order to obtain long-range-order nanofabrication. The first guide pattern is comprised only of a post lattice. The second guide pattern adds guide lines to the post lattice. The added guide lines are expected to better control the location and orientation of the BCP nanodots. We succeeded in fabricating these two kinds of guide patterns for 22-nm- and 33-nm-pitch BCP nanodots.

We have prototyped illumination-collection mode scanning near-field optical microscopy (SNOM) and near-field Raman spectroscopy (NFRS) with gold inner-covered aperture-less pyramidal probe in order to study the possibility to detect optical images, and Raman spectrum and Raman peak shift for stress distribution in Si device with high resolution of about 10 nm.

In this study, we investigated the possibility of forming the fine Si dot arrays by means of electron beam (EB) lithography and dry etching technique for the future’s devices with nano-scale structures. We examined the properties of Ar ion milling for the fabrication of nanometer sized Si dot arrays on a Si substrate. We have succeeded in forming 40 nm pitched Si dot arrays with a diameter of

Reliability (or stability) of multi-level storage (MLS) is the critical characteristics for multi-level cells. In order to improve reliability of MLS of phase-change memory, there are two effective approaches, (i) enlargement of the ratio between resistance levels and (ii) reduction of scattering of resistance level. On the basis of our experimental results, it is demonstrated that the Ge2Sb2Te5-based double-layered cell has a high ratio of highest to lowest levels up to two-to-three orders of magnitude, implying high reliability. The cells exhibit the possibility of stable switching for four-level storage.

The possibility of realizing femtogram mass detection using a frame-type microcantilever has been studied in bioscience. To realize highly sensitive mass detection by reducing the viscose resistance in liquids, we designed frame-type cantilevers using finite element modeling (FEM). We fabricated prototypes of mesh-type, hole-type and conventional-type cantilevers using a semiconductor process. The properties of the cantilevers were measured by a conventional atomic force microscope (AFM) system. The measured resonance frequencies of the cantilevers were almost consistent with the calculated results of the FEM simulation in air. The resonance frequency and quality (Q) factor of the mesh-type cantilever were larger than those of the conventional-type cantilever in water. We measured the frequency change due to gold film deposition on the mesh-type cantilever. Then, we estimated the mass sensitivity of the cantilever at about 16.6 fg/Hz. This value is more than 10 times smaller than that of the conventional-type cantilever. These results indicate that the mesh-type cantilever has the advantage of reducing the viscous resistance and achieving high sensitivity in liquids.

Rapid growth of soft electronics has enabled various approaches for developing artificial skin. However, currently existing electronic skin is still facing some problems such as high fabrication complexity, high production cost, and smartness of recognizing the stimulus automatically. In this work, we report a simple, low-cost Polydimethylsiloxane (PDMS)-based smart electronic skin system, consisting of a sensor array and a data processing system. The sensor array can be easily mounted on the human body or robot hand as a result of excellent softness, stretchability, and bendability of PDMS. Signals from the sensor array are processed by a Long and Short Term Memory neural network algorithm in the data processing system. The trained data processing system can recognize four types of gestures at an accuracy of 85 ± 5%, even taking into account environmental variations including folding, curvature, tensile strength, temperature, and endurance cycles. This work proves that this type of skin can be endowed with intelligence with a proper neural network algorithm and fabricated at low cost and reduced complexity. Published version

The switching time of a Ag2S atomic switch, in which formation and annihilation of a Ag atomic bridge is controlled by a solid-electrochemical reaction in a nanogap between two electrodes, is investigated as a function of bias voltage and temperature. Increasing the bias voltage decreases the switching time exponentially, with a greater exponent for the lower range of bias than that for the higher range. Furthermore, the switching time shortens exponentially with raising temperature, following the Arrhenius relation with activation energy values of 0.58 and 1.32 eV for lower and higher bias ranges, respectively. These results indicate that there are two main processes which govern the rate of switching, first, the electrochemical reduction Ag+ + e−→Ag and, second, the diffusion of Ag+ ions. This investigation advances the fundamental understanding of the switching mechanism of the atomic switch, which is essential for its successful device application.

We developed a micro-magnetometry with a 2.5 μm spatial resolution based on micro X-ray magnetic circular dichroism (XMCD) technique in order to study magnetic properties of dot arrays for bit-patterned media. This micro-magnetometer was applied to the magnetic characterization of Co–Pt dot arrays fabricated by ion beam etching. As the dot size became small, the intensity of XMCD drastically decreased for dots fabricated by Ga-focused ion beam. This suggested that the dot edges were damaged magnetically by implantation of Ga ions. The damaged width of the dot edge was estimated to be about 13 nm from the decrease in XMCD intensities. This damaged edge width agreed with the ion-implanted area estimated by Monte-Carlo simulation. The less-damaged effect of Ar ion etching was verified by the XMCD measurement of Co–Pt dots with diameter of 20 and 70 nm. It was concluded that ions with inertness, lower energy and smaller atomic number should be used to fabricate dot arrays with an areal density of 1 Tbit/in2.

We studied methods of estimating three-dimensional (3-D) tip structure using impulse response technique. We have proposed a 3-D tip estimation method using an infinite small diameter standard column as the impulse response technique. The standard column has been made by image processing of a finite-small-diameter-column standard sample by a software elimination technique. We demonstrated how to obtain the 3-D atomic force microscope (AFM) pyramidal tip shape using a commercial pyramidal tip and a 665-nm-diameter-column sample. The estimated tip radii are 10–15 nm in various profiles of the top. The results indicate that the method is effective to estimate a 3-D AFM tip structure in order to obtain an accurate AFM image.

The possibility of forming very fine pits or dots with a pitch of less than 25nm was researched using electron beam (EB) drawing, reactive ion etching (RIE), and nano-imprinting for the future lithographic production of patterned media. We were able to fabricate ultrahighly packed dot arrays with a dot diameter of less than 15nm and a dot pitch of 25nmx25nm in negative calixarene resist using EB drawing. We also formed Si dot arrays patterns by CF"4-RIE. Furthermore, pit arrays were formed in polymer film through nano-imprinting by the photo-polymer method using a Si dot arrays pattern as the master mold. We demonstrated that the EB-drawn dot arrays resist pattern is very suitable for the fabrication of Si dot arrays and pit arrays with a pitch of 25nmx25nm in this polymer, which corresponds to a storage density of about 1Tb/in^2 in patterned media. The Si dot and pit diameters were less than 10nm.

X-ray diffraction patterns and resistivity measurement indicate that as-deposited N-doped Sb"2Te"3 (STN) films become amorphous while the as-deposited Sb"2Te"3 film is crystalline. A lateral as-deposited STN-based multi-layer phase change memory was proposed for multi-state storage. The active region of the device consists of a top 30-nm TiN/180-nm STN/20-nm TiN/bottom 120-nm STN stacked multi-layer. Static switching properties of the device with STN initially starting from the amorphous state exhibit two apparent S-shaped switchings, which correspond to two marked device resistance drops by a factor of 2-5. The first and second threshold voltages are around 2.8-3.2 and 4.3-5.4V, respectively. Finite element analysis of the device shows that the two switchings could sequentially occur at the electrode steps from the bottom 120-nm STN layer to the top thick 180-nm STN layer.

The possibility of forming very fine pits or dots with a bit pitch (BP) and a track pitch (TP) of 25nm was investigated using a conventional electron-beam (EB) writing system and positive and negative EB resists ZEP520 and calixarene, respectively. In our experiments, we obtained very small dots with a diameter of around 13nm, and ultrahigh-density dot arrays with a BP and a TP of 25nm using calixarene resist. Calixarene resist is very suitable for the formation of ultrahigh-packed dot array patterns, and promises to open the way toward 1trillion bits/in^2 storage. We believe that calixarene is more suitable for ultrahigh-density pattern formation than ZEP520 because of its exposure intensity distribution function and its resist structure.

In this paper, we describe the fabrication of erbium disilicide (ErSi"2) nanowires on clean silicon surfaces by self-assembled epitaxial growth due to a lattice mismatch between ErSi"2 and silicon substrate. As surface treatment and surface orientation were important for controlling the nanowire growth, we formed a clean surface of Si(001)2x1 and Si(110)1x1. Then, ErSi"2 nanowires were formed on the silicon surface by solid phase epitaxial growth. The silicon surfaces and the nanowires were observed using ultrahigh vacuum scanning tunneling microscopy (UHV-STM). The length of the nanowires on the Si(001) surface ranged from a few 10s of nm to a few 100s of nm, and the growth occurred in the orthogonal two-way directions of Si[110] and Si[11@?0]. Although the length of the nanowires on Si(110) was almost the same as that on Si(001), the growth occurred in the one-way direction of Si[110]. This result indicates that the growth direction of the self-assembled nanowires can be controlled by the Si surface orientation.

We developed an atomic switch consisting of an ionic and electronic mixed conductor electrode and a counter metal electrode, having a space of about 1 nm between them. Formation and annihilation of a conductive atomic bridge is controlled using a solid electrochemical reaction, which is caused by applying a certain bias voltage between the electrodes. In this study, we measured the switching time of atomic switches made of silver sulfide and copper sulfide. The switching times were different, and this difference can be attributed to the different activation energies and chemical potentials of the materials.

We prototyped phase-change (PC) channel transistors and demonstrated two functions of nonvolatile memory and channel current control. We have developed prototype transistors that use a PC channel instead of a silicon channel. The PC material of a Ge2Sb2Te5 thin film with a thickness of 50 nm was used. We demonstrated a memory function whereby we achieved a reversible change between the crystalline and amorphous phases by applying a source-drain (SD) voltage for Joule heating. In the experiment, the applied voltages for PC between amorphous and crystalline phases were from 5 to 8 V. Control of the channel current was realized by applying a gate bias. The SD current was suppressed to less than 1/20 of that at a gate bias of -3 V by applying a gate bias of 0-3 V

We have studied a possibility to form nanometer-sized optical probe using prototype atomic force cantilevered SNOM and some fine structure samples. The system has an ability to obtain both atomic force microscope (AFM) and scanning near-field microscope (SNOM) images simultaneously. The fine optical probe was studied using the outside and inside Au coated SNOM probe. As experimental results, we have obtained a 10 nm-sized optical probe by observations of magneto-optical (MO) disc and Au thin film with many fine cracks.

Although synaptic behaviours of memristors have been widely demonstrated, implementation of an even simple artificial neural network is still a great challenge. In this work, we demonstrate the associative memory on the basis of a memristive Hopfield network. Different patterns can be stored into the memristive Hopfield network by tuning the resistance of the memristors, and the pre-stored patterns can be successfully retrieved directly or through some associative intermediate states, being analogous to the associative memory behaviour. Both single-associative memory and multi-associative memories can be realized with the memristive Hopfield network.

A confined-chalcogenide (CC) cell structure for reducing the reset current of phase-change random access memory (PRAM) is proposed in this investigation. Both single normal-bottom-contact (NBC) (for reference) and proposed CC PRAM cells are simulated by two-dimensional finite element modelling. The simulated amorphous region of the NBC cell after reset operation is generally a semiellipse, which agrees very well with the reported experimental results. The CC cell has a rectangular amorphous region after reset operation. The reset operation current of the CC cell is much lower than that of the NBC cell. The CC cell structure needs a low reset current and a low power consumption and has a simple configuration.

We have fabricated and studied single lateral phase-change random-access-memory (PRAM), which has a confined Ge2Sb2Te5 (GST) channel connected by two wide TiN electrodes of relatively low resistivity. Its switching current for Reset operation could be as low as 4–20 µA, about one or two orders of magnitude lower than that of the conventional bottom contact PRAM cell. Its corresponding switching power for Reset operation is about 2–4 µW. The reason for such ultra low Reset current and power could be that Joule heating occurred mainly in the GST channel, instead of the resistive heater in the conventional PRAM cell.

We have developed a novel AFM (atomic force microscope) measurement technique which can examine side-walls of fine patterns etched into wafers. This technique uses a sharpen tip tilted at an angle in combination with a "step-in" mode operation, and is thus referred as "tilt-step-in" mode. This method allows one to measure side wall shape including under cut and line edge roughness (LER).

A novel memory effect in metal–chalcogenide–metal structures was observed using chalcogenide films connected by two Al electrodes. A bias polarity-dependent switching between a high (RESET) and low (SET) resistance state was observed in current–voltage characteristics of the structure when sweeping voltage in forward and backward directions. The reversible SET/RESET switching was induced by voltage pulses and their polarity. The resistances of the structure changed over a range of approximately two orders of magnitude. In readouts of the resistance, we obtained its retention time for data over 17 days at room temperature.

The possibility of realizing femtogram mass detection using a piezoresistive microcantilever has been studied for bioscience applications. The mass detection was undertaken by employing the resonance frequency shift of a cantilever. In the experiments, we measured the change in the mass of adsorbed water molecules and the reaction between an antigen and an antibody on the cantilever from the resonance frequency shift. We used a prototype and a commercially available piezoresistive cantilever. The sensor was formed by using Wheatstone bridge circuits, a positive feedback controller, a piezoactuator and a phase-locked loop (PLL) demodulator. A mass sensitivity of around 200 fg/Hz and a noise level of about 12 fg were estimated experimentally from the water molecules adsorbed on the cantilever. We also confirmed that the sensor could detect an antigen and antibody reaction in an egg allergy test.

We studied phase-change channel transistor memory devices with an ultrathin Ge2Sb2Te5 chalcogenide film channel and tried to demonstrate two combined functions (memory: resistance change and selection: channel current control) by annealing in this paper. Drain–source resistance can be markedly decreased by 2 – 3 orders of magnitude after annealing due to the phase change from the amorphous to crystalline phases. A channel current control effect in which the drain current decreases with the gate voltage was clearly observed in 10- and 20-nm-thick Ge2Sb2Te5 devices. The absolute channel current modulation by the gate voltage in the crystalline state is much stronger than that in the amorphous state. Furthermore, the channel current control ability in devices with thin Ge2Sb2Te5 is stronger than that in devices with thick Ge2Sb2Te5. The channel current control effect might result from the potential change of the ultrathin Ge2Sb2Te5 channel by the gate voltage. [DOI: 10.1143/JJAP.45.3238]

Possibility of very fine bit arrays formation for an ultrahigh density optical and magnetic recordings has been researched using electron beam (EB) writing with a high resolution scanning electron microscope (SEM), a writing controller and positive and negative electron resists. As experimental results, calixarene negative EB resist is very suitable to form an ultrahigh packed bit arrays pattern. We obtained extremely fine dot arrays with a diameter of

A novel method to form Ag nano-dot pattern on Ag"2S surface has been demonstrated using electron beam (EB) irradiation. When we irradiated EB in raster-scanning mode on Ag"2S surface, we observed nano-protrusions growth on the surface. We consider that the protrusion must be made of Ag. For point EB irradiation, a nano-dot having a minimum diameter of 13nm was obtained. We also demonstrated the writing of the nano-letters, ''GUNMA UNIV.'' with each character having a width of less than 600nm, and the forming of a nano-dot array pattern with a dot-size of about 25nm and dot-pitch of 30nm, which corresponds to about 600Gb/in^2 for storage applications.

A self-sensing mass biosensor with a femtogram mass sensitivity has been developed using a piezoresistive microcantilever. The mass change due to antigen and antibody adsorption on the cantilever in water was detected by the resonance frequency shift of the cantilever. We constructed a prototype harmonic vibration sensor using a commercial piezoresistive cantilever, Wheatstone bridge circuits, a positive feedback controller, an exciting piezoactuator and a phase-locked loop (PLL) demodulator. As experimental results, a mass sensitivity of about 190 fg/Hz, and a mass resolution of about 500 fg were obtained in water. The mass sensitivity is 100 times higher than that of a quartz crystal oscillation method. We demonstrated that the sensor can detect the reaction between an antibody of immunoglobulin (IgG) and an antigen of egg albumen (OVA). We confirmed that the binding ratio between the antibody and the antigen was about 1 : 2. The detection method is available for allergy check because the measured reaction ratio occurring on the cantilever concurs with the theoretical method.

We have developed a new type AFM (Atomic force microscopy) for semiconductor wafer testing with coarse-fine movement mechanisms, coarse XY stage and fine xy scanner. XY scanner was used both sample positioning and AFM scanning, A unique birds-beak type z-scanner was designed to be constructed with an optical microscope. Firstly we examined basic characteristics of each positioning mechanisms, 20 mm positioning with coarse-fine control in 0.25 s, 2 nm step moving with xy scanner. Secondary the resolution of the AFM system with 0.3 nm and the frequency response with 1 kHz in AFM operation were measured. Finally as AFM observations, a compact disc surface and bare-Si surface of 0.19 nm Ra were clearly measured. We confirmed the usefulness of the new AFM mechanism.