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Jörn Stenger
A NEW LEVEL OF JOINT, COORDINATED METROLOGY RESEARCH: THE EMRP

European metrology research has taken an unprecedented step towards scientific, management and financial integration. The projects in the 63 M€ ERANETplus programme “iMERA-plus” are coming to an end and the first projects of the 400 M€ Article-185 initiative “European Metrology Research Programme, EMRP” have started. The EMRP is characterized by a joint research strategy, joint execution structures and processes in EURAMET and stable national financial commitments.

H. Imai
HOW TO EXPRESS THE RELIABILITY OF MEASUREMENT RESULTS - THE ROLE OF METROLOGICAL TRACEABILITY AND MEASUREMENT UNCERTAINTY

Recent situation on global metrology is reviewed from the view point of requirements of science and technology. Basic infrastructure on quantities and units is built up under the international recognition and rules in science of measurement. Metrological traceability to a metrological reference such as a measurement unit, a reference procedure, and a reference material is considered to be fundamentals in calibration and measurement. In order to confirm the reliability of a measurement result, statement of metrological traceability chain together with attributed measurement uncertainty is required for calibration and testing laboratories. Concepts and definitions of terms are documented in such as SI brochure, VIM, GUM and some other standard documents of ISO, IEC, OIML and ILAC. In Mutual Recognition Arrangement (MRA) such as CIPM and ILAC, statements of competence for both quality management system and technology based on ISO/IEC 17025 are required. Detailed description on metrological traceability and measurement uncertainty for a measurement result is also required in many fields of science, industry and our social life from the safety point of view.

Hyuksang Kwon, Soo Jin Kim, Eun Ji Noh, Seon Hwa Park, Nam Woong Song
DEVELOPMENT OF STANDARD MEASUREMENT PROTOCOL FOR THE SIZE ANALYSIS OF SiO2 NANOPARTICLES USING A SCANNING ELECTRON MICROSCOPY

The size and size distribution of materials are important factors for understanding the characteristics of nanomerterials. Although transmission electron microscopy (TEM) is a powerful tool for determining the nanomaterial size, the nanoparticle cast on carbon-film for the TEM sampling exhibits limitation in size measurement due to agglomeration during the solvent elimination. By using scanning electron microscopy (SEM), such limitation can be overcome by modifying the surface of substrate for sampling. Here, we show that the size measurement of well-defined SiO2 nanoparticles could be performed with minimized sampling issues. The experimental conditions such as a working distance, an accelerating voltage, a filament current and a metal coating were adjusted to optimize imaging condition. Experimental uncertainties were also derived from the consideration of uncertainty factors and measurement of CRM for SEM imaging.

Min Gyu Park, Se-Bum Choi, Nam Woon Kim, Hyunung Yu
RAMAN ANALYSIS ON NANOCRYSTALLINE SILICON FILM

A compact dot marker using a cw laser on a microcrystalline silicon (µc-Si:H) thin film is demonstrated. Annealing process using a laser leads to a continuous crystallization from nano to sub-micron domain (> 50 nm) of Si nanocrystals within the thin film. This patterning is quite useful because we can manipulate 2-D process of silicon structural forms for an efficient thin-film transistor (TFT) devices with respect to uniform electron mobility. A Raman microscope is quite useful to reveal a crystal volume fraction with a calculation from the population ratio between crystalline and amorphous phase.

Yoon-Young Choi, Moonkyu Park, Jongin Hong, Kwangsoo No
FABRICATION AND CHARACTERIZATION OF FERROELECTRIC POLY (VINYLIDENE FLUORIDE -CO -TRIFLUOROETHYLENE) NANODOTS

We demonstrated a facile route to fabricate ferroelectric poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), nanodots from spin-coated thin films. Importantly, the discrete P(VDF-TrFE) nanodots possessed high degree of β-phase [F(β) > 60%] when compared to the fraction of β-phase in thin films [F(β) = 51%]. P(VDF–TrFE) nanodots of (51.4 ± 10.6) nm in height and (172.75 ± 40.5) nm in diameter displayed superior piezoresponse values (18.1 ± 3.3) pm/V and a low coercive voltage (2.4 ± 0.5) V. This offers our rationale for a great promise in non-volatile memories, infrared sensor arrays and artificial skin applications.

S.J. Kim, N.W. Song
OBSERVATION OF TIME EVOLUTIONARY PHYSICOCHEMICAL PROPERTY OF SILICA NANOPARTICLES AS CRM CANDIDATES

The necessity for the synthesis of nanomaterials (NMs) with well-controlled physicochemical properties is emerging with the development of nanoindustry and advanced applications of nanomaterials in biomedical fields. In this study, we observed time evolution of physicochemical properties of silica nanoparticles (SiO2 NPs) as candidates of certified reference materials (CRM) for size analysis. We have validated the size stability of spherical SiO2 NPs exhibiting diameters of 30 and 40 nm in diameter for one year.

Junjie Liu, Wenge Zhang
NANOPARTICLE SIZE MEASUREMENT BY NANOPARTICLE TRACKING ANALYSIS (NTA) METHOD

Nanoparticle Tracking Analysis (NTA) is a newly developed method, and in the measure process, there are several factors and parameters which have significant effect on the accuracy of final mean particle size result. In this paper, we analysis the effect of sample concentration, camera parameters (shutter, gain and duration) and analysis parameter (threshold) on the obtained NTA results. Based on the work, appropriate methods about sample preparation and parameters settings in video capturing and analysis process are developed by measuring a polystyrene sample with nominal value of 80 nm.

Youngdo Jung, Young Hwa Lee, Junhyuk Kwak, Shin Hur
DEVELOPMENT OF CAPACITIVE TYPE MEMS MICROPHONE WITH SIMULATION AND ELECTRO-MECHANICAL CHARACTERIZATION

Capacitive type MEMS microphone was designed, fabricated and characterized. Finite element model was used in the design process of the MEMS microphone and the fabrication was carried out using MEMS fabrication process including low stress silicon nitride membrane deposition and eutectic bonding process. The simulation results show that the designed MEMS microphone has the resonant frequency above the operation frequency range and the sensitivity of 9.1 mV/Pa (@18V). The experimental results show that the MEMS microphone has 3 dB cut-off frequency of 144 kHz.

Hyunwoo Choi, Yunseok Kim, Seungbum Hong, Kwangsoo No
DOMAIN STRUCTURES OF FERROELECTRIC LEAD TITANATE NANOTUBES FABRICATED AT VARIOUS TEMPERATURES

We studied the domain structures of ferroelectric PbTiO3 nanotubes (NTs) fabricated at various temperatures, using piezoresponse force microscopy (PFM). PTO NTs fabricated at above 500 °C underwent mechanical fracture through development of nanocracks due to grain growth, leading to ferroelectric domains with larger size and lower aspect ratio.

G. Bas, P. Demircioglu, N. M. Durakbasa, P. H. Osanna
A NANOMETROLOGICAL MANAGEMENT APPROACH TO ASSESS THE PROFILE AND THE SURFACE CHARACTERISTICS OF THE END MILLING TOOLS BY MULTI-MEASUREMENT ANALYSIS

The competitive machining industry requires modern milling tools and their flexible, high quality and powerful industrial implementations. The main factors effecting the operational quality of the end milling tools are tool material, coating and edge geometry. This study represents the assessment of the coating and the surface characteristics of the end milling tools by contact (stylus profilograph) and non-contact mode nanometrological devices (digital microscope, 3D laser scanner) to establish a methodology to assess the micro/nanogeometry of the coated and uncoated tools with an effort to predict the surface roughness effect. This approach introduces a wide application of knowledge extraction to supervise the end milling operation by ensuring the operational quality of the tools where high accuracy and good quality surface is demanded.

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