The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Yoshiro Yamada - One of the best experts on this subject based on the ideXlab platform.
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in situ si wafer surface temperature measurement during flash lamp annealing
Japanese Journal of Applied Physics, 2010Co-Authors: Yoshiro Yamada, Juntaro Ishii, Takayuki Aoyama, Hajime Chino, Kensuke Hiraka, Satoru Kadoya, Shinichi Kato, H Kiyama, Hideki Kondo, Tohru KuroiwaAbstract:Automatic emissivity compensating Radiation thermometry based on polaradiometry was applied to in situ wafer surface temperature measurement on a flash lamp annealing prototype system. The developed temperature measurement system consists of a dual polarization Radiation Thermometer and a modulating reference light source, which were mounted on two opposing ports of the process chamber. The intense background Radiation from the flash lamp was successfully suppressed by introducing a water flow layer beneath the flash lamp unit and measuring at the water absorption band of 1.95 µm. Millisecond heating and cooling of the wafer was measured for various operating conditions of the flash lamp and for various silicon wafers including wafers with microstructures. The peak temperature was compared with the sheet resistance after treatment and device properties after fabrication. Good correlation was confirmed between sheet resistance and measured peak temperature for various flash lamp intensities irrespective of the surface emissivity or heating conditions. Transistor threshold voltage showed similar correlation, which verifies the applicability of the developed Thermometer system to in situ measurement during production.
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performance evaluation of wc c peritectic high temperature fixed point
2009 ICCAS-SICE, 2009Co-Authors: Naohiko Sasajima, Yoshiro YamadaAbstract:WC-C peritectic fixed point (2749 °C) was investigated to evaluate their potential of serving as high-temperature reference points in thermometry. Four WC-C peritectic cells were constructed and the melting and freezing plateaus were evaluated by means of Radiation Thermometer. The repeatability of the melting temperature of one cell was 0.011 K with the melting range of 0.117 K. The melting temperatures of four different cells were agreed within 0.05 K. The long term stability of WC-C cell was also evaluated by the realization of 45 melt/freeze cycles. The standard deviation of 45 melting temperatures was 0.034 K including the instability of LP3. From these results, it can be concluded that WC-C peritectic fixed point has a high potential to be used as a high temperature reference point. The microstructure analyses of WC-C peritectic cells by means of optical microscopy and electron-probe microanalysis (EPMA) showed the segregation of the graphite in the WC-C cell.
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investigation of wc c peritectic high temperature fixed point
Society of Instrument and Control Engineers of Japan, 2007Co-Authors: Naohiko Sasajima, Yoshiro YamadaAbstract:WC-C peritectic (2749degC) fixed point was investigated to evaluate their potential of serving as high-temperature reference points in thermometry. Three WC-C fixed-point cells were constructed and the melting and freezing plateaus were evaluated by means of Radiation Thermometer. The repeatability of the melting temperature of WC-C peritectic in one day was 17 mK with the melting range of approximately 70 mK. The repeatability of the freezing temperature of WC-C peritectic was 21 mK with the freezing range of less than 20 mK. The WC-C cells were easily constructed, like metal-carbon eutectic cells, without any reaction with crucible. From these results, it is concluded that WC-C peritectic has more potential as high-temperature standards than TiC-C eutectic (2761degC).
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metal carbide carbon peritectic systems as high temperature fixed points in thermometry
Metrologia, 2006Co-Authors: Yoshiro Yamada, Y Wang, Naohiko SasajimaAbstract:WC?C, Cr3C2?C and Mn7C3?C peritectic systems were investigated for their potential of serving as high-temperature reference points in thermometry. Mixtures of high-purity graphite powder with W, Cr and Mn powder of 99.99%, 99.9% and 99.95% purity by mass, respectively, were placed in graphite blackbody crucibles and melting/freezing plateaus were observed by means of a Radiation Thermometer. The observed melting temperatures were 2749??C (WC?C), 1826??C (Cr3C2?C) and 1331??C (Mn7C3?C), with a repeatability?in each case?of 0.02?K. The melting range for WC?C and Cr3C2?C peritectics was roughly 0.1?K. WC?C showed a flat freezing plateau that agreed with the melting plateau within the repeatability. The three fixed points are possible candidates, like the metal (carbide)?carbon eutectic fixed points, in the realization of an improved high-temperature scale above the copper point.
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metal carbide carbon eutectic and peritectic fixed points as high temperature standards
2006 SICE-ICASE International Joint Conference, 2006Co-Authors: N Sasajima, Yoshiro Yamada, Y WangAbstract:TiC-C eutectic and WC-C peritectic systems were investigated for their potential of serving as high-temperature reference points in thermometry. Mixtures of high-purity graphite powder with Ti and W were filled in graphite crucibles and melting/freezing plateaus were observed by means of a Radiation Thermometer. The observed melting range of WC-C peritectic was roughly 0.1 K with repeatability of 0.02 K. The melting range of TiC-C eutectic was roughly 0.5 K with repeatability of 0.09 K. The freezing curve of TiC-C showed a sharp peak after recovery from supercool, followed by a gently-sloped curve, probably due to composition of eutectic ingot or impurities. WC-C peritectic seems to have more potential as high-temperature standards, although it is still at a preliminary stage of investigation.
Bonghak Kim - One of the best experts on this subject based on the ideXlab platform.
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spectral responsivity calibration of the reference Radiation Thermometer at kriss by using a super continuum laser based high accuracy monochromatic source
Metrologia, 2016Co-Authors: Y. S. Yoo, Seongchong Park, D. H. Lee, Gun Jung Kim, Bonghak KimAbstract:We report on the calibration of the relative spectral responsivity of the reference Radiation Thermometer, model LP4, which is used for the experimental realisation of the international temperature scale of 1990 above 960 °C at the Korea Research Institute of Standards and Science. The relative spectral responsivity of LP4 is measured by using a monochromatic source consisting of a super-continuum laser and a double-grating monochromator. By monitoring the wavelength of the output beam directly with a calibrated wavelength-meter, we achieved a high-accuracy measurement of spectral responsivity with a maximum wavelength error of less than 3 pm, a narrow spectral bandwidth of less than 0.4 nm, and a high dynamic range over 8 decades. We evaluated the contributions of various uncertainty components of the spectral responsivity measurement to the uncertainty of the temperature scale based on a practical estimation approach, which numerically calculates the maximal effects of the variations of each component. As a result, we evaluate the uncertainty contribution from the spectral responsivity measurement to the temperature scale to be less than 64 mK (k = 1) in a range from 660 °C to 2749 °C for the LP4 with a filter at 650 nm.
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validation of the fixed point realization of the thermocouple scale using a Radiation Thermometer in the temperature range between the freezing points of ag and pd
Metrologia, 2010Co-Authors: Yonggyoo Kim, Bonghak Kim, Inseok YangAbstract:We have developed a blackbody comparison system to validate the fixed-point realization of the thermocouple temperature scale using the Radiation thermometry scale. Platinum/palladium, type S and type B thermocouples were calibrated at the fixed points of Ag, Cu, Fe?C, Co?C and Pd (only for type B). The Radiation Thermometer used was an LP4 linear pyrometer operating at a central wavelength of 650?nm. To assign the Fe?C eutectic melting temperature in our laboratory, a radiometric Fe?C cell was fabricated, and its melting temperature was determined as (1154.0 ? 0.1)??C with k = 2. Two scales were compared from 962??C to 1555??C in the blackbody comparison system. The two scales were consistent within 0.5??C up to 1400??C, but the discrepancy for the type B thermocouple increased to 2.3??C at 1554.8??C. The thermocouple and radiometric scales realized at our laboratory were in agreement up to the freezing temperature of Pd within the measurement uncertainty.
Howard W. Yoon - One of the best experts on this subject based on the ideXlab platform.
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measurement of thermal Radiation using regular glass optics and short wave infrared detectors
Optics Express, 2008Co-Authors: Howard W. Yoon, George P. EppeldauerAbstract:The measurement of thermal Radiation from ambient-temperature objects using short-wave infrared detectors and regular glass optics is described. The detectors are chosen to operate in the 2.0 µm to 2.5 µm atmospheric window. Selection of detectors with high shunt resistance along with the 4-stage thermo-electric cooling of the detectors to -85 °C results in detectivity, D*, of 4×1013 cm Hz1/2/W which is near the background limited performance at 295 K. Furthermore, the use of regular-glass commercial optics to collect the thermal Radiation results in diffraction-limited imaging. The use of a Radiation Thermometer constructed with these elements for the measurement of a blackbody from 20 °C to 50 °C results in noise-equivalent temperature difference (NETD) of <3 mK at 50 °C. The operation at shorter wavelengths than traditional thermal sensors also leads to lower sensitivity to the emissivity of the object in determining the temperature of the object. These elements are used to construct a calibrator for an infrared collimator, and such a system demonstrates noise-equivalent irradiances of <5 fW/cm2. These results indicate that radiometers using short-wave infrared sensors could be constructed utilizing commercial glass optics with possible better performance and lower NETD than existing radiometers using cryogenically-cooled mid-infrared or thermal infrared detectors.
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sse and noise optimized ingaas Radiation Thermometer
International Journal of Thermophysics, 2007Co-Authors: Howard W. Yoon, Charles E. Gibson, V B Khromchenko, George P. EppeldauerAbstract:For measurements of radiance temperatures in the range from 150°C to 1,000°C, low uncertainties in the temperature measurements can be achieved by using near-infrared InGaAs Radiation Thermometers. The design and construction of the NIST near-infrared Radiation Thermometer (NIRT) that is optimized for low size-of-source effect (SSE) and noise-equivalent temperatures are described. The NIRT utilizes a 50 mm diameter achromatic objective lens with low scatter that images a 4.5 mm diameter spot at a distance of 50 cm from the objective in an on-axis design. A Lyot stop is implemented in the design with the aperture stop placed after the field stop resulting in a collection f/12. A 3 mm diameter InGaAs detector is cooled to − 70°C using a four-stage thermoelectric cooler to obtain high-shunt resistance for linear, low-noise operation at high transimpedance amplifier gains. For thermal and structural stability, the optical components are placed on four, 15 mm diameter graphite-epoxy rods making the optical throughput stable. Optical ray tracing with a commercial program is used to determine the Strehl ratio and other imaging parameters. A possible approach for a detector-based temperature scale in this range which could result in 10 mK (k = 2) thermodynamic temperature uncertainties at the In-point is discussed.
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Thermodynamic-temperature determinations of the Ag and Au freezing temperatures using a detector-based Radiation Thermometer
Applied Optics, 2007Co-Authors: Howard W. Yoon, Charles E. Gibson, Steven W. Brown, Maritoni Litorja, David W. Allen, George P. Eppeldauer, Keith R. LykkeAbstract:The development of a Radiation Thermometer calibrated for spectral radiance responsivity using cryogenic, electrical-substitution radiometry to determine the thermodynamic temperatures of the Ag- and Au-freezing temperatures is described. The absolute spectral radiance responsivity of the Radiation Thermometer is measured in the NIST Spectral Irradiance and Radiance Responsivity Calibrations using Uniform Sources (SIRCUS) facility with a total uncertainty of 0.15% (k=2) and is traceable to the electrical watt, and thus the thermodynamic temperature of any blackbody can be determined by using Planck Radiation law and the measured optical power. The thermodynamic temperatures of the Ag- and Au-freezing temperatures are determined to be 1234.956 K (±0.110 K) (k=2) and 1337.344 K(±0.129 K) (k=2) differing from the International Temperature Scale of 1990 (ITS-90) assignments by 26 mK and 14 mK, respectively, within the stated uncertainties. The temperatures were systematically corrected for the size- of-source effect, the nonlinearity of the preamplifier and the emissivity of the blackbody. The ultimate goal of these thermodynamic temperature measurements is to disseminate temperature scales with lower uncertainties than those of the ITS-90. These results indicate that direct disseminations of thermodynamic temperature scales are possible.
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the nist eutectic project construction of co c pt c and re c fixed point cells and their comparison with the nmij
Metrologia, 2006Co-Authors: Charles E. Gibson, Howard W. Yoon, Fumihiro Sakuma, V B Khromchenko, N Sasajima, Yoshiro YamadaAbstract:The National Institute of Standards and Technology (NIST) has initiated a project on novel high-temperature fixed-points by use of metal (carbide)–carbon eutectics to lower uncertainties in thermodynamic temperature measurement. As the first stage of the NIST eutectic project, a comparison of Co–C, Pt–C and Re–C eutectic fixed-point cells was conducted between the NIST and the National Metrology Institute of Japan (NMIJ) at the NIST to verify the quality of the NIST eutectic cells in addition to checking for possible furnace and Radiation Thermometer effects on the eutectic fixed-point realizations. In the comparison, two high-temperature furnaces, two Radiation Thermometers and one gold-point blackbody were used. A Nagano M furnace and a Linear Pyrometer 3 Radiation Thermometer were transferred from NMIJ and were used in conjunction with a Thermo Gauge furnace and an Absolute Pyrometer 1 Radiation Thermometer of NIST to check the dependence on the measurement equipment. The results showed that Co–C cells agreed to 73 mK. The melting temperature of the NIST Pt–C cell was approximately 270 mK lower than that of the NMIJ cell, with a comparison uncertainty of roughly 110 mK (k = 2), due to the poor purity of Pt powder. Although the Re–C comparison showed instability of the comparison system, they agreed within 100 mK. Though further improvement is necessary for the Pt–C cell, such as the use of higher purity Pt, the filling and measuring technique has been established at the NIST.
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methods to reduce the size of source effect in radiometers
Metrologia, 2005Co-Authors: Howard W. Yoon, David W. Allen, Robert D SaundersAbstract:In radiometry, photometry and Radiation thermometry, accurate measurements of the radiance, luminance or the radiance temperatures of sources requires a knowledge of the contribution from the surroundings to the measured signal from the target area. The dependence of the radiometer or the Radiation Thermometer on the area surrounding the target area is described as the size-of-source effect (SSE), and minimizing the radiometer's sensitivity to SSE is critical in the lowest-uncertainty optical measurements. We describe the dominant effects that influence the SSE, and show that the SSE can be reduced to <5 ? 10?5 as measured using a 50?mm diameter radiance source with a 2?mm diameter, central obscuration. The SSE is found to be dependent on the internal scatter and the optical design of the radiometer. For testing the contributions to SSE, a radiometer is constructed with a 50.8?mm diameter lens in f/12 geometry with a 1?mm diameter target size. If the internal radiometer scatter is reduced, then the SSE is found to be primarily dependent on the scatter from the objective lens such as surface finish, internal lens scatter and the particulate contamination of the lens. Various combinations of objective lenses are measured for SSE, and the relative merits of increasing optical performance at the expense of additional optical elements are also discussed.
Fumihiro Sakuma - One of the best experts on this subject based on the ideXlab platform.
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development of a new ingaas Radiation Thermometer at nmij
International Journal of Thermophysics, 2008Co-Authors: Fumihiro Sakuma, Tadashi KobayashiAbstract:The first InGaAs Radiation Thermometer at NMIJ was developed more than ten years ago as a standard Radiation Thermometer operating from 150 to 1,100°C. Its size-of-source effect (SSE) was as large as 1% from 6 mm in diameter to 50 mm in diameter. The new Thermometer has an SSE of 0.3%. The reason for the error in measuring the SSE of InGaAs Thermometers was also found. The new Thermometer at first suffered from nonlinearity and the distance effect (DE). These deficiencies arose from the misalignment of optics inside the Thermometer and were solved by increasing the detector size from 1 mm in diameter to 2 mm in diameter. Unfortunately, the detector of 2 mm diameter had a smaller S/N ratio than that of the 1 mm one at the indium (In) point. The final design uses a detector of 1 mm diameter, but the Radiation is focussed on a smaller area of the detector. The new Thermometer is smaller and lighter than preceding designs and other standard InGaAs Radiation Thermometers. The temperature of the main part of the instrument, including the filter, the detector, and the preamplifier board, is controlled at 30°C. In addition to the calibration with the six fixed points of copper (Cu), silver (Ag), aluminum (Al), zinc (Zn), tin (Sn), and indium (In), the linearity from the In point to the Cu point, the SSE, the DE, and the spectral responsivity were measured.
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the nist eutectic project construction of co c pt c and re c fixed point cells and their comparison with the nmij
Metrologia, 2006Co-Authors: Charles E. Gibson, Howard W. Yoon, Fumihiro Sakuma, V B Khromchenko, N Sasajima, Yoshiro YamadaAbstract:The National Institute of Standards and Technology (NIST) has initiated a project on novel high-temperature fixed-points by use of metal (carbide)–carbon eutectics to lower uncertainties in thermodynamic temperature measurement. As the first stage of the NIST eutectic project, a comparison of Co–C, Pt–C and Re–C eutectic fixed-point cells was conducted between the NIST and the National Metrology Institute of Japan (NMIJ) at the NIST to verify the quality of the NIST eutectic cells in addition to checking for possible furnace and Radiation Thermometer effects on the eutectic fixed-point realizations. In the comparison, two high-temperature furnaces, two Radiation Thermometers and one gold-point blackbody were used. A Nagano M furnace and a Linear Pyrometer 3 Radiation Thermometer were transferred from NMIJ and were used in conjunction with a Thermo Gauge furnace and an Absolute Pyrometer 1 Radiation Thermometer of NIST to check the dependence on the measurement equipment. The results showed that Co–C cells agreed to 73 mK. The melting temperature of the NIST Pt–C cell was approximately 270 mK lower than that of the NMIJ cell, with a comparison uncertainty of roughly 110 mK (k = 2), due to the poor purity of Pt powder. Although the Re–C comparison showed instability of the comparison system, they agreed within 100 mK. Though further improvement is necessary for the Pt–C cell, such as the use of higher purity Pt, the filling and measuring technique has been established at the NIST.
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calibration and characterization of the transfer standard Radiation Thermometer for an apmp intercomparison
TEMPERATURE: Its Measurement and Control in Science and Industry; Volume VII; Eighth Temperature Symposium, 2003Co-Authors: Fumihiro Sakuma, Ma LainaAbstract:An Asia‐Pacific Metrology Program (APMP) key comparison of radiance temperature in 0.65 μm was carried out from 1997 to 2000 among seven institutes: NMIJ, KRISS, NIM, CSIRO, NMC, KIM‐LIPI and ITRI. Afterward an APMP supplementary comparison of radiance temperature in 0.9 μm was started. Both of the comparisons employ a transfer standard Radiation Thermometer as a transfer instrument. This paper describes the calibration and characterization of the 0.65 μm transfer‐standard Radiation Thermometers. The 0.65 μm Thermometer was calibrated according to the ITS‐90. A copper‐point calibration, spectral responsivity measurement and nonlinearity measurement were carried out. The measured spectral responsivity was multiplied by the Planck equation and was integrated over wavelength. The coefficient was determined by the copper‐point calibration. The integral scale of the output V at temperature T was approximated by an interpolation equation, V(T)=C/[exp{c2/(AT+B)}−1]. Here c2 is the second Radiation constant and t...
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calibration and characterization of chino 900 nm silicon narrow band Radiation Thermometer
Society of Instrument and Control Engineers of Japan, 2002Co-Authors: Fumihiro SakumaAbstract:This paper describes the calibration and characterization of the Chino 900 nm standard Radiation Thermometer, IR-RST-90 W. The gain ratio, fixed-point calibrations, spectral responsivity, nonlinearity, size-of-source effect, distance effect, zero-offset stability and temperature drift were measured. Some problems were found for this Thermometer regarding the out-of-band suppression, the size-of-source effect and the temperature drifts. A new type Radiation Thermometer was manufactured for improving the quality to use as a standard Radiation Thermometer.
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international comparison of Radiation temperature scales among five national metrological laboratories using a transfer Radiation Thermometer
Metrologia, 1996Co-Authors: Fumihiro Sakuma, Charles E. Gibson, H Sakate, G Machin, T Ricolfi, M Battuello, Carol B Johnson, J Fischer, H J JungAbstract:Round-robin measurements with a transfer standard Radiation Thermometer were organized by the NRLM in the framework of a three-year joint research agreement with the NIST, the IMGC and the PTB: the NPL also took part in this exercise. The aim of the study was to assess the mutual traceability of the ITS-90 temperature scales established by the different laboratories in the high-temperature range (above 1000 °C). The Thermometer was a monochromatic (0,65 µm) silicon-detector Thermometer belonging to the NRLM. It was circulated in the period from May to July 1993 and was calibrated by all the participants against their local reference Thermometers. The temperature interval from 1000 °C to 2000 °C was covered by all the participants, but some extended the range down to 800 °C or up to 2700 °C. The results indicate that all the calibrations agree to within 0,5 °C at 1000 °C and to within 2 °C at 2000 °C.
Janko Drnovšek - One of the best experts on this subject based on the ideXlab platform.
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calculated uncertainty of temperature due to the size of source effect in commercial Radiation Thermometers
International Journal of Thermophysics, 2008Co-Authors: Igor Pušnik, Goran Grgić, Janko DrnovšekAbstract:The article evaluates the uncertainty in the temperature indicated by a Radiation Thermometer with a direct readout in temperature, due to the uncertainty in measuring the size-of-source effect (SSE) by the so-called “direct method.” Radiation Thermometers of this type are the ones most frequently used in practice. The uncertainty of the SSE characteristic is usually not a useful quantity to report to users of commercial Radiation Thermometers. Instead, they would prefer to know the uncertainty in the measured temperature that results from the uncertainty of the SSE characteristic, and this will be the result of our analysis. The user of a direct reading Radiation Thermometer will be able to take into account the uncertainty of temperature due to the SSE, if a target with known dimensions is measured. The uncertainty in temperature due to the SSE of analyses based on Planck’s law and its approximation, Wien’s law is compared.
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system for the determination of the size of source effect of Radiation Thermometers with the direct reading of temperature
Measurement Science and Technology, 2006Co-Authors: Igor Pušnik, Goran Grgić, Janko DrnovšekAbstract:The paper describes a system for the determination of the size-of-source effect (SSE) of Radiation Thermometers with the direct reading of temperature, which form the majority of commercial Radiation Thermometers. Optics in every Radiation Thermometer (RT) gathers Radiation from a larger area than is defined by the nominal target size. Thus, a measured temperature is more or less dependent on available target area. Every Radiation Thermometer suffers from the SSE. We developed a system, based on a water-cooled holder, for measuring the SSE by a direct method. The system could be placed in front of any blackbody. Manufacturing of such a system was relatively easy and could be important for users of commercial Radiation Thermometers because the majority of those Thermometers have direct reading of temperature. We measured the SSE characteristics by the direct method for a Radiation Thermometer with a linearized signal and direct reading of temperature. The results of the SSE were analysed for the direct method without correction of the background Radiation and with correction of the background Radiation. Knowledge about the SSE characteristic of a Radiation Thermometer is one of the key elements for correct temperature measurement.
