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Particle size distribution (PSD) analysis for nanoparticle is important for quality management of CMP slurry, that used in chemical mechanical polishing (CMP) process. CMP slurry contains poly-dispersed particles, which consist of size-different primary particles and secondary particles in suspension. It is difficult to measure PSD for poly-dispersed particle using Dynamic Light Scattering, which is one of a typical method to evaluate PSD for mono-dispersed particles. The image analysis is also employed for PSD analysis. For image analysis, it needs to transfer the particles from suspension to a substrate before measurement. In this procedure, some particles aggregate with surrounding particles. It causes the difference between the PSD for dispersed particles in suspension and the PSD for observed particle using image analysis. In addition, concentration measurement is important for quality management of CMP slurry. Mass concentration is used in concentration evaluation for CMP slurry. However, it is difficult to identify the molar concentration for multi-modal particles, respectively. In this study, we suggested a method to define molar concentration spectra to express both a modal diameter and molar concentration for multi-modal nanoparticles to evaluate the CMP slurry. In order to measure the molar concentration spectra, we suggested a novel particle sizing method using nanoparticle chip (NPC) to measure number-weighted mean particle diameter, a variance of diameters, and molar concentration for every spectrum. Nanoparticles grid on a substrate to maintain the poly-dispersed condition in suspension to process NPC. NPC can assist the image analysis process to measure the PSD of particles in suspension. The number of particles, that aligned on the substrate, can be counted to measure the molar concentration. In this paper, a fundamental experiment was performed to investigate the feasibility of molar concentration spectra measurement. It is confirmed the molar concentration spectra for poly-dispersed particles can be measured by using NPC and it is considered that PSD with molar concentration spectra can give detail information of abrasive grain in suspension for quality management of CMP slurry.

Colloidal ceria is expected to be a candidate of alternative slurry for glass substrate CMP because the slurry particles are small and have a regular shape comparing to conventional calcined ceria particles. Thanks to the characteristics, the colloidal ceria can generate a high quality surface in glass substrate CMP, but removal rate (RR) is smaller than that of calcined ceria. In order to improve the RR, KOH was added to the colloidal ceria. KOH additives make colloidal ceria particles aggregate and improve RR close to that of calcined ceria. By evaluating the extent of aggregation with and without ultrasonic dispersion, it was found there was a strong correlation with KOH concentration to aggregation strength and RR. To obtain further RR and to reduce the consumption of slurry, influence of polishing pressure and slurry concentration on polishing characteristics was investigated. As the polishing pressure increased, the RR improved, while slurry residue occurred partly on the edge of the substrate surface. The slurry residue was restrained by decreasing slurry concentration. Furthermore, although scratches in the nanometer order increase slightly under high polishing pressure, they are smaller than those by calcined ceria slurry. By controlling the degree of aggregation of colloidal ceria, we have achieved both high RR and high quality surface.

Atomic force microscopy (AFM) is an effective platform for in vitro manipulation and analysis of living cells in medical and biological sciences. To introduce additional new features and functionalities into a conventional AFM system, we investigated the photocatalytic nanofabrication and intracellular Raman imaging of living cells by employing functionalized AFM probes. Herein, we investigated the effect of indentation speed on the cell membrane perforation of living HeLa cells based on highly localized photochemical oxidation with a catalytic titanium dioxide (TiO2)-functionalized AFM probe. On the basis of force&ndash, distance curves obtained during the indentation process, the probability of cell membrane perforation, penetration force, and cell viability was determined quantitatively. Moreover, we explored the possibility of intracellular tip-enhanced Raman spectroscopy (TERS) imaging of molecular dynamics in living cells via an AFM probe functionalized with silver nanoparticles in a homemade Raman system integrated with an inverted microscope. We successfully demonstrated that the intracellular TERS imaging has the potential to visualize distinctly different features in Raman spectra between the nucleus and the cytoplasm of a single living cell and to analyze the dynamic behavior of biomolecules inside a living cell.

In this paper, lapped C-face of single crystal SiC wafer was irradiated by femtosecond laser. Chemical mechanical polishing (CMP) was then carried out to polish the irradiated SiC C-face. The authors compared the results of femtosecond laser-assisted CMP process. A white-light interferometer was used to investigate the surface morphology of the processed SiC substrate before and after laser irradiation. It was found that the material removal rate (MRR) of the irradiated substrate is about 3 times higher than that of the substrate not treated by femtosecond laser. In addition, lower surface roughness was realized after femtosecond laser assisted CMP process.

When a microsphere is trapped near a surface by single-beam gradient force trapping, the standing wave is generated between the microsphere and the surface, where abrupt motion along the optical axis (jumping) is observed corresponding to displacement of the surface. This jumping distance is on the order of a few hundred nanometers. In the vicinity of the surface, intensity of retro-reflected light is increased so that the averaged position of the jumping is shifted up on the order of several micrometers. Therefore wide-range and high-resolution position measurement technique is required. In this article, we proposed to apply a chromatic confocal sensor to measure the axial position of the microsphere in the standing wave. It was experimentally validated that the position of the microsphere could be measured with a resolution of 10 nm and a measuring range of 3 µm.

Demand for applications of nanoparticles in electric architecture has been increasing. Nanoparticles provide new opportunities for improving circuit response. We discuss a novel method for evaluating nanoparticle sizes based on fluorescence anisotropy analysis. Particle size evaluation is possible through measurements of the rotational diffusion coefficient, which is sensitive to particle size. We develop a system for measuring rotational diffusion coefficients by using a fluorescent probe to label a particle. We report fundamental experiments that verify the feasibility of the proposed method. The rotational diffusion coefficients of gold nanoparticles with diameters ranging 6–20 nm were measured using the proposed method. The measured rotational diffusion coefficients decrease with increasing particle size. This finding indicates that nanoparticles smaller than 15 nm can be measured with fine resolution.

We calculate the electron excitation in cubic silicon carbide (3C-SiC) caused by the intense femtosecond laser double pulses using time-dependent density functional theory (TDDFT). We assume the electron distributions in the valence band (VB) and the conduction band (CB) based on three different approaches to determine the dependence of the plasma that is formed on the excitation by the first pulse. First, we consider the simple double pulse irradiation, which does not include the electron-electron collisions and relaxation. Second, we consider the partially thermalized electronic state, in which the electron temperatures and numbers in the VB and the CB are defined independently. This assumption corresponds to the plasma before the electron-hole collisions becomes dominant. The third approach uses the fully thermalized electron distribution, which corresponds to a timescale of hundreds fs. Our results indicate that the simple double pulse approach is the worst of the three, and show that the plasma formation changes the efficiency of the excitation by the second pulse. When the electron temperature decreases, the laser excitation efficiency increases as a result.

In the present study, a sensitive and accurate isotope dilution method was developed for the simultaneous determination of 17 polar pharmaceutical and personal care product (PPCP) residues (log Kow = 1.40–5.74), including 14 pharmaceuticals and 3 personal care products, in biological organs and tissues. The proposed method involved enzymatic hydrolysis, followed by sequential clean-up using silica gel chromatography and gel permeation chromatography, and analysis via ultra-high-performance liquid chromatography with tandem mass spectrometry. This method yielded acceptable absolute recoveries (48–88%) and internal standard-corrected recoveries (90–130%) for 17 PPCPs. Method detection limits were between 0.0092 and 3.2 ng g−1 wet weight, and the limits of quantification were between 0.020 and 8.7 ng g−1 wet weight. The method can be used to readily detect the target compounds at trace levels while minimizing the required sample volume. The developed method was applied to the determination of 17 PPCPs in the liver and kidney of 17 birds collected from Japan and also in the plasma, liver, and brain of 7 cyprinoid fish from an effluent-dominated stream in Japan. Triclosan was detected in 5 of 11 fish-eating birds but not in non-fish-eating birds, suggesting the contamination of prey fish by the chemical. Non-steroidal anti-inflammatory drugs, antibacterial agents, and psychotropic agents were frequently detected in the fish tissues. In addition, 7 of the target compounds were found in fish brain. The median brain/plasma ratios of the psychotropic agents ranged from 1.6 (carbamazepine) to 12 (diphenhydramine), indicating high transportability to fish brain.

Surface with nanometer accuracy is required to manufacturing process of integrated circuit (IC) devices. One of the most promising techniques for surface planarization is chemical mechanical polishing (CMP). CMP is a high efficiency process, both due to the varied chemical and physical properties of the surface materials. Conventional CMP uses the slurry, which is composed of abrasive particles suspended in a chemical solution. The abrasive particle is effective for surface planarization by a chemical mechanism with little mechanical abrasion. So chemical reactivity appears to be an essential factor of CMP process. In our conventional study, fullerenols have been proposed as suitable abrasives for copper CMP. The chemical reactivity of fullerenol is suggested by the fact that high removal rate (150 nm/min) and surface flatness (0.6 nm RMS) have been confirmed using fullerenol slurry. In this study, we analyzed the chemical reactivity between fullerenol molecule and copper surface, which is important to understand the material removal mechanism. Using the intrinsic Raman spectroscopic signal of interaction between fullerenol and copper with surface plasmon resonance (SPR), the chemical reactivity over a period of the reaction process was analyzed. Raman spectroscopy is commonly used in chemical analysis, since vibrational information is specific to the chemical bonds and symmetry of molecules. Therefore, it provides a fingerprint by which the molecule can be identified. However, spontaneous Raman spectroscopic signal is typically very weak, and as a result the main difficulty of Raman spectroscopy is separating the weak inelastically scattered light from the intense Rayleigh scattered laser light. Then Raman spectroscopic signal in this study is further enhanced by the SPR, also known as surface enhanced Raman scattering (SERS). The increase in intensity of the Raman spectroscopic signal for adsorbates on copper surface occurs because of an enhancement in the electric field provided by the surface. This technique enables high-sensitive analysis in the near-surface region. The signature of copper-oxygen bond was measured by Raman spectroscopy for fullerenol/copper system by in-process SERS analysis. It is thought to be caused by the hydroxyls of fullerenol molecule adsorbed on the copper surface. This result suggests that fullerenol molecules absorbing onto the copper surface affect the high efficient material removal.

A surface imaging technique using a laser-trapped microsphere is proposed. The goal of this research is to image the surface texture, while simultaneously measuring the position of the engineered surfaces using the laser-trapping-based microprobe. This paper presents an investigation of imaging characteristics for the microsphere technique. Depending on the distance from the surface to the microsphere, the available images could be either real or virtual. Virtual images had a higher contrast than real images. Contrast and magnification varies depending on the positions of the focal point of the objective lens and surface.

Probe calibration contributes to the measurement uncertainty of micro-coordinate measuring machines (micro-CMMs). This study proposes a new method of measuring stylus sphere diameters for micro-CMMs based on the analysis of whispering gallery modes (WGMs). Depending on the incident wavelength, different WGMs will be excited in the probe stylus, resulting in a wavelength spectral fingerprint that is related to the sphere diameter. In this paper, the diameter of the microprobe stylus sphere was determined with a least-squares method using theoretical and measured spectra of WGMs. The measurement results showed that the precision of the proposed method was ±1 nm.

A three-dimensional probe is mounted on a specialized gear measuring machine whose measurement target is limited on the working flanks. The newly developed measuring machine has a coordinate measuring mechanism, aiming to be a highly versatile and relatively inexpensive measuring machine. According to our previous research, in addition to the working tooth surface, shape data of the root, bottom and tip profiles can be acquired with a single measurement operation. However, the target object for which this developed method has been applied was only the external cylindrical gear. In this paper, we applied and expanded the development method to the internal cylindrical gear and the evaluation of the axial displacement in the same cross-sectional scanning of the internal helical gear are performed.

Laser trapping is becoming an important technique for microsystem technologies. To apply it to industrial uses, it should be developed to function in air. However, there is not much research about laser trapping in air. One of the reasons is the difficulty of trapping micro-objects. Therefore, we have proposed a new technique to trap micro-objects in air. In particular, we focused our attention on the substrate where the micro-object is set. By applying a textured surface and employing tungsten carbide as the substrate material, the trapping probability was improved by a remarkable amount. Although a certain degree of improvement was attained, the trapping was still not perfect. To ascertain the forces working on the micro-object, an analytical calculation of the adhesion forces and an electromagnetic simulation of the optical forces were implemented. Based on these calculations, we discuss what the most important factor is for successful laser trapping in air.

In Cu-CMP using a fullerenol slurry, effective planarization in terms of high removal rate has been confirmed. The high chemical reactivity of fullerenol is suggested to be an essential factor for copper material removal. In situ surface analysis based on the SERS method was performed to reveal the role of the copper–fullerenol interaction in the chemical reaction process during Cu-CMP. A series of SERS Raman spectra suggested that a reacted thin film formed on the copper surface, which was measured using a custom-built measurement system.

The nondestructive, non-contact, three-dimensional evaluation of optical glass has been important to the manufacturing of high-precision optical components. In order to achieve high-precision nondestructive evaluation of optical heterogeneity, we develop a versatile evaluation system using the parallel phase- shift digital holography, which enables measurements of the optical path differences at a nanometer-scale resolution. The amplitude and phase distributions of the object wave can be reconstructed directly from a single hologram by using the parallel phase-shift digital holography system. The optical heterogeneity of a sample is determined quantitatively based on the distribution of the optical path differences quantitatively.

When a laser pulse interacts with metal or semiconductor target, the coherent phonon, which is the coherent motions of lattice and molecule vibrations in solids, is excited by the interaction of electrons and high latitude electric field. It has unique properties of decaying in approximately several picoseconds and substance specific frequency. Owing to that, femtosecond laser processing is the local processing with little heat diffusion and little thermal damage to the target, due to the ultrafast time scales. We propose a novel femtosecond pulse ablation process with oscillation of the coherent phonon by femtosecond pulse train. The pulse train is shaped using Spatial Light Modulator (SLM), which shift the phase of the passing light. And coherent phonon oscillations are enhanced and decayed due to the controlling the shape of pulse train. It is able to activate the lattice motion for processing efficiently, and hence the target is expected to be ablated with high accuracy and less thermal damage.

We proposed a novel technique for self-assembly of micro parts by using DNA hybridization. As the demand for MEMS is growing, research on the self-assembly of micro parts is required to achieve fabrication of functional devices consisted of diverse micro parts. Our method has a unique characteristic where the selective assembly can be performed. At the targeted substrate region functionalized by single-stranded DNA, only components functionalized by the complementary one are assembled successfully. This is due to the complementary properties of DNA, which consists of four different bases (adenine (A), cytosine (C), guanine (G), and thymine (T)). A of one strand always pairs with a T of another, and so does C with G. The characteristic enables batch fabrication of diverse micro parts by using several kinds of DNA properly. Therefore, our method can be applied to the fabrication of MEMS. In this paper, in order to verify the feasibility of the automatic positioning using DNA hybridization, we performed a fundamental experiment for addressing polystyrene microspheres (1, 2, 6μm diameter) on the DNA patterned glass substrate.