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At the National Metrology Institute of Japan (NMIJ), a new monochromator-based absolute radiometric calibration system for radiation thermometers has been developed with a supercontinuum (SC) source instead of a tungsten-halogen lamp. Compared with halogen lamps, remarkably higher spectral radiance can be obtained from the SC-monochromator-based system because the SC optical radiation can be efficiently coupled into the narrow entrance slit of the monochromator, thus enabling coupling of the monochromatic light from the exit slit into an integrating sphere, which serves as a wavelength-tunable source for calibrating radiation thermometers against a reference detector. In this work, the setup and preliminary measurement results of the SC-source-based system at the NMIJ are described. Techniques for power stabilization, wavelength determination, spatial-uniformity improvement, and interference fringe reduction are applied to the system. The uncertainties of the facility for thermodynamic temperature measurements are estimated.

Application of radiation thermometry in industrial scenes is rapidly increasing with the widespread use of low-cost infrared thermometers and thermal imagers. However, their performances are not always up to the users’ expectations. This is often due to lack of appropriate information on the limitations of the instrument performance and of radiation thermometry itself. In this article, these limitations are disclosed, namely the targeting capabilities of the thermometers including the size-of-source effect of thermal imagers, reflection errors, and unknown emissivity of the measurement object. Attempts made at the NMIJ are introduced, which aim at alleviating the effect of these difficulties. Two-color radiation thermometers have been neglected from the traceability chain and from standardization efforts due to their technical complexity. Recent activities to incorporate them effectively in the calibration chain and to establish international standards are presented. Calibration of low-cost thermometers with a fixed instrumental emissivity setting has been an issue for calibration laboratories. Simple apparatus that enables calibration of such instruments is described. Methods to compensate for unknown emissivities are presented utilizing auxiliary sources to realize a blackbody condition, which is applied to thermal imagers to overcome the problem of the size-of-source effect and reflection error at the same time. Extensions of the technique to objects with specular and scattering surfaces are described. Such efforts are encouraged in the thermometry community since they are essential in establishing an unbroken chain of traceability to the industrial front.

New Asia Pacific Metrology Programme (APMP) comparisons of radiation thermometry standards, APMP TS-11, and -12, have recently been initiated. These new APMP comparisons cover the temperature range from $$156\,^{\circ }\hbox {C}$$ to $$2800\, ^{\circ }\hbox {C}$$ . Three radiation thermometers with central wavelengths of 1.6 $$\upmu \hbox {m}$$ , 0.9 $$\upmu \hbox {m}$$ , and 0.65 $$\upmu \hbox {m}$$ are the transfer devices for the radiation thermometer scale comparison conducted in the so-called star configuration. In parallel, a compact fixed-point blackbody furnace that houses six types of fixed-point cells of In, Sn, Zn, Al, Ag, and Cu is circulated, again in a star-type comparison, to substantiate fixed-point calibration capabilities. Twelve APMP national metrology institutes are taking part in this endeavor, in which the National Metrology Institute of Japan acts as the pilot. In this article, the comparison scheme is described with emphasis on the features of the transfer devices, i.e., the radiation thermometers and the fixed-point blackbodies. Results of preliminary evaluations of the performance and characteristic of these instruments as well as the evaluation method of the comparison results are presented.

Calibration of infrared radiation thermometers at non-unity emissivity settings is a poorly solved problem for establishment of traceability to meet user needs, for instruments with both fixed and variable emissivity setting functions. A variable-temperature gray-body radiator having a constant value of emissivity independent of both wavelength and temperature can be a perfect tool for the calibration purpose. In this paper, two types of high-transmittance optical neutral density filters, one utilizing a rotating-sector optical chopper, and another of a wire-mesh type, are shown to perform well with a precise transmittance between 90 % and 100 % in the wide infrared wavelength range. These optical filters in combination with a blackbody cavity traceable to ITS-90 can realize reliable gray-body radiation. These methods are applied successfully to several models of infrared thermometers operated in the emissivity correction mode.

A pilot comparison of radiance temperature scale realizations between the National Institute of Metrology Thailand (NIMT) and the National Metrology Institute of Japan (NMIJ) was conducted. At the two national metrology institutes (NMIs), a 900 nm radiation thermometer, used as the transfer artifact, was calibrated by a means of a multiple fixed-point method using the fixed-point blackbody of Zn, Al, Ag, and Cu points, and by means of relative spectral responsivity measurements according to the International Temperature Scale of 1990 (ITS-90) definition. The Sakuma–Hattori equation is used for interpolating the radiance temperature scale between the four fixed points and also for extrapolating the ITS-90 temperature scale to 2000 $$^{\circ }$$ C. This paper compares the calibration results in terms of fixed-point measurements, relative spectral responsivity, and finally the radiance temperature scale. Good agreement for the fixed-point measurements was found in case a correction for the change of the internal temperature of the artifact was applied using the temperature coefficient measured at the NMIJ. For the realized radiance temperature range from 400 $$^{\circ }$$ C to 1100 $$^{\circ }$$ C, the resulting scale differences between the two NMIs are well within the combined scale comparison uncertainty of 0.12 $$^{\circ }$$ C ( $$k=1$$ ). The resulting spectral responsivity measured at the NIMT has a comparable curve to that measured at the NMIJ especially in the out-of-band region, yielding a ITS-90 scale difference within 1.0 $$^{\circ }$$ C from the Cu point to 2000 $$^{\circ }$$ C, whereas the realization comparison uncertainty of NIMT and NMIJ combined is 1.2 $$^{\circ }$$ C ( $$k=1$$ ) at 2000 $$^{\circ }$$ C.

SUMMARY Using a small-size crucible, interlaboratory comparison of the realization of the Co−C eutectic point was performed in the industrial field in Japan, with the aim of verifying the possibility of thermocouple calibration at the eutectic point with an existing furnace of less-than-ideal temperature distribution, namely, the palladium-point wire-bridge method furnace for thermocouple calibration. A small-size crucible for thermocouples was made by the National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). The interlaboratory comparison was piloted by the Tokyo Metropolitan Industrial Technology Research Institute (TIRI), a public test and research organization in Tokyo, and was conducted among five calibration laboratories including the pilot. One of the five laboratories is a designated calibration laboratory in Japan, and the other three are private laboratories. Four laboratories including TIRI used an existing palladium-point furnace, and one laboratory made a new furnace for this interlaboratory comparison.

This article describes the results of the bilateral comparison of blackbodies for infrared ear thermometers (IRETs) between the National Institute of Metrology (Thailand), NIMT, and the National Metrology Institute of Japan (NMIJ). The purpose of this comparison was to ensure consistency of the national radiance temperature scales for IRETs maintained by NIMT and NMIJ. Results of the measurements indicate differences in radiance temperature within 10 mK with a maximum measurement uncertainty of 64 mK. The equivalence of the radiance temperature scales realized by both NIMT and NMIJ in the range of 35 $$^{\circ }$$ C to 42 $$^{\circ }$$ C for IRET calibration is indicated. The results of this bilateral comparison can be used in terms of quality assurance and validation of calibration.

A novel retarding type electron energy analyzer implementing an electrostatic lens system to achieve a high energy resolution sufficient to measure thermodynamic temperature has been investigated b...

The National Measurement Institutes (NMIs) of the United States, Germany, France, Italy and Japan, have joined in an inter-laboratory comparison of their infrared spectral emittance scales. This action is part of a series of supplementary inter-laboratory comparisons (including thermal conductivity and thermal diffusivity) sponsored by the Consultative Committee on Thermometry (CCT) Task Group on Thermophysical Quantities (TG-ThQ). The objective of this collaborative work is to strengthen the major operative National Measurement Institutes’ infrared spectral emittance scales and consequently the consistency of radiative properties measurements carried out worldwide. The comparison has been performed over a spectral range of 2 μm to 14 μm, and a temperature range from 23 °C to 800 °C. Artefacts included in the comparison are potential standards: oxidized inconel, boron nitride, and silicon carbide. The measurement instrumentation and techniques used for emittance scales are unique for each NMI, including the temperature ranges covered as well as the artefact sizes required. For example, all three common types of spectral instruments are represented: dispersive grating monochromator, Fourier transform and filter-based spectrometers. More than 2000 data points (combinations of material, wavelength and temperature) were compared. Ninety-eight percent (98%) of the data points were in agreement, with differences to weighted mean values less than the expanded uncertainties calculated from the individual NMI uncertainties and uncertainties related to the comparison process.

The NMIJ has established a new calibration facility consisting of a 1.6μm radiation thermometer and three fixed-point blackbodies of indium (156.5985 °C), tin (231.928 °C), and zinc (419.527 °C) in the temperature range from 160 °C to 420 °C. The expanded uncertainties (k = 2) of the fixed-point blackbodies are estimated to be 28 mK for the In point, 22 mK for the Sn point, and 32 mK for the Zn point. The expanded uncertainties in the temperature scale of the 1.6μm radiation thermometer are estimated to be 40 mK to 77 mK. When this standard is used to calibrate devices under test to be used in industry, uncertainties (k = 2) of 61 mK for the In point, 67 mK for the Sn point, and 99 mK for the Zn point, 91 mK to 136 mK for a 1.6μm radiation thermometer, and 73 mK to 116 mK for a variable-temperature blackbody can be achieved.

An overview is presented on the activity with industrial partners to solve problems at the production sites in the semiconductor industry. Based on a survey on temperature needs and techniques in the semiconductor device fabrication industry, two target processes with the most pressing demands for in situ temperature measurements were selected: plasma etching and flash lamp annealing (FLA). A novel approach for emissivity compensated radiation thermometry was applied to sub-millisecond response measurement for FLA. The approach has features that make it suitable for in situ applications. Results of thermal profile measurements conducted on a FLA chamber are described.

Photoelectron spectroscopy as a practical method for measuring thermodynamic temperature is investigated. The present analysis is based on the sensitivity of the Fermi–Dirac distribution function to temperature variation, and the effect of energy resolution of the photoelectron measurements on the resulting temperature determination. A newly designed electron energy analyzer implementing an einzel lens system is presented. From simulations of electron trajectories, the energy resolution of the analyzer was estimated to be 2 meV which is sufficient to achieve an accuracy better than 1 K for the temperature range from 25 K to 300 K.

A thermoreflectance temperature measuring system was developed with the aim to realize monitoring of the silicon wafer surface temperature during plasma etching. The thermoreflectance detects variations in temperature through changes in optical reflectance. To overcome such difficulties as low sensitivity and limitation in installation space and position for in situ measurements, the differential thermoreflectance utilizing two orthogonal polarizations was introduced. Noise such as fluctuations in the incident beam intensity or changes of loss in the optical path would affect both polarizations equally and would not affect the measurement. The large angle of incidence of the beam allows measurement to be performed from outside the viewing ports of existing plasma etching process chambers through the gap between the plasma electrode and the silicon wafer. In this article, an off-line measurement result is presented, with results for bare wafers as well as for wafers with metal depositions. A prototype system developed for tests in plasma etching facilities in a production line is described.

Among all known materials, we found that a forest of vertically aligned single-walled carbon nanotubes behaves most similarly to a black body, a theoretical material that absorbs all incident light. A requirement for an object to behave as a black body is to perfectly absorb light of all wavelengths. This important feature has not been observed for real materials because materials intrinsically have specific absorption bands because of their structure and composition. We found a material that can absorb light almost perfectly across a very wide spectral range (0.2–200 μm). We attribute this black body behavior to stem from the sparseness and imperfect alignment of the vertical single-walled carbon nanotubes.

The NMIJ has established a temperature scale for infrared radiation thermometry from 100 to 420°C consisting of three fixed-point blackbodies at the In, Sn, and Zn points and an InSb detector thermometer at a wavelength of 4.7 μm. The blackbody cavities have large openings of 15 mm diameter. The expanded uncertainties (k = 2) of the In, Sn, and Zn fixed-point radiance temperatures are estimated to be 0.03, 0.03, and 0.05 K, respectively. The expanded uncertainties (k = 2) for the calibration of the infrared radiation thermometer are estimated to be 0.04 K at 157°C (In point), 0.04 K at 232°C (Sn point), and 0.07 K at 420°C (Zn point).

Below the freezing point of silver, radiation thermometers are generally calibrated by implementing the multi-point interpolation method using blackbody measurements at three or more calibration points, rather than the ITS-90 extrapolation technique. The interpolation method eliminates the need to measure the spectral responsivity and provides greater accuracy at the longer wavelengths required below the silver point. This article identifies all the sources of uncertainty associated with the interpolation method, in particular, those related to the reference blackbody temperatures (either variable-temperature or fixed-point blackbodies) and to the measured thermometer signals at these points. Estimates are given of the ‘normal’ and ‘best’ uncertainties currently achievable. A model of the thermometer response is used to propagate all the uncertainties at the reference points and provide a total uncertainty at any temperature within the calibration range. The multi-point method has the effect of constraining the total uncertainty over this range, unlike the ITS-90 technique for which the uncertainties propagate as T 2. This article is a joint effort of the working group on radiation thermometry of the Consultative Committee for Thermometry (CCT), summarizing the knowledge and experience of all experts in this field.

Infrared ear thermometer was developed and rapidly spread in Japan in the late 1990's, but users began to question the reliability of the temperature readings. AIST developed a new national standard for the calibration and conformity assessment of new ear thermometers, and also designed and organized the traceability system, conducted technological verification, and improved reliability of measured temperature, to meet the demands of Japanese industry and consumers. An international comparison of national measurement standards among Germany, UK, and AIST was conducted and the equality of the standards was experimentally verified to maintain international reliability.

A new infrared radiation thermometer having a high temporal response and a high spatial resolution is being developed at NMIJ to meet the existing demand for measurements of thermophysical properties of thin films, coatings, and solids in microscale. The thermometer consists of a photovoltaic (pv)-type of mercury cadmium telluride (MCT) detector and a compact Cassegrain type of mirror optics without a mechanical chopper. The performance of the thermometer has been well characterized experimentally. Sensing infrared radiation around 10 μm of wavelength, the thermometer covers the temperature range from −50 to 150°C and has a temperature resolution better than 0.3°C at −50°C for blackbody radiators. The spatial resolution has also been checked by using a test pattern (USAF 1951) for rating the resolution of optical systems. Temperature changes of specimen surfaces in periodic heating with a laser beam modulated above 100 kHz have been observed successfully with the thermometer. The results shows that the thermometer has great potential for measuring the thermal diffusivity, thermal conductivity, and specific heat capacity of microscale substances at low temperatures based on the periodic heating and pulsed laser heating methods.

The performance of two single pixel, large area quantum well infrared photodetectors (QWIPs) were compared with that of a commercially available 2 mm diameter photovoltaic (PV) HgCdTe detector. Parameters which were compared include the absolute spectral responsivity, noise equivalent power (NEP), spatial uniformity of response, non-linearity and stability. Both detector types were shown to have sufficiently high spectral responsivity and D* values to satisfy a number of applications in infrared radiometry when operated at 77 K. However, the spatial non-uniformity of response of both QWIPs examined was unacceptably high. Furthermore the spatial uniformity of response of the same detectors was shown to be strongly dependent on the state of polarisation of the incident radiation as well as also exhibiting some dependency on wavelength. The spatial uniformity of response of the PV HgCdTe detector was shown to be very poor due to the very low shunt resistance of this detector. However, it exhibited no polarisation dependency and only a slight dependency on wavelength for wavelengths below 5 μm. Neither detector type could be considered for high accuracy radiometric applications in their current form.

The thermal diffusivity of thin metal films has been measured by combining a fast infrared radiation thermometer with a mercury cadmium telluride (MCT) detector and a CO2 laser modulated at a radio frequency up to 2 MHz. The laser output beam modulated by an acousto-optic modulator (AOM) is directed to the front surface of the blackened copper thin film (10μm thick, 9.5 mm in diameter). The thermal radiation from the back surface of the sample is detected. From the observed phase delay in the detected signal of 0.68 radian to the input laser beam, the thermal diffusivity is determined to be 1.11 × 10-4m2·s-1, which agrees well with the value of 0.99 × 10-4m2·s-1 calculated from literature results. The method is generally applicable for measurements of thermal properties of nano/micro materials.

We devised a new method of determining the temperatures of materials with their electron-energy distributions. The Fermi–Dirac distribution convoluted with a linear combination of Gaussian and Lorentzian distributions was fitted to the photoelectron spectrum measured for the Au(110) single-crystal surface at liquid N2-cooled temperature. The fitting successfully determined the surface-local thermodynamic temperature and the energy resolution simultaneously from the photoelectron spectrum, without any preliminary results of other measurements. The determined thermodynamic temperature was 99 ± 2.1 K, which was in good agreement with the reference temperature of 98.5 ± 0.5 K measured using a silicon diode sensor attached to the sample holder.

Two dimensional thermal imagers are becoming widely applied to monitoring heat dissipation in designing and fabricating electronic devices. However, the true local surface temperature is usually not obtained without rigorous calibration, due to difficulties such as unknown emissivity, poor imaging quality of the optics, and background radiation. In this presentation, a method to overcome these issues are presented, which makes use of the emissivity distribution pattern detected by the thermal imager by superimposing a modulated background radiation. In particular, in this article, the size-of-source effect caused by the poor imaging quality of the imager is shown to be overcome by the proposed method.

A Fourier transform infrared (FTIR) spectrometer was developed to measure spectral radiance of thermal-infrared emission near ambient temperatures with high accuracy at the NMIJ (former NRLM). The spectrometer uses a simple Michelson interferometer that consists of corner cube mirrors and a KBr beam splitter. The spectral range between 5 µm and 12 µm was covered by a liquid nitrogen cooled photovoltaic HgCdTe detector operated in the photoamperic mode. Opaque solid samples with good thermal conductivity were heated directly by the thermostatic fluid up to 100 °C. To reduce the effect of absorption by air, all of the optical components were operated in the vacuum. The spectrometer was calibrated against two high quality reference blackbodies: a fixed-temperature blackbody cooled by liquid nitrogen and a variable-temperature blackbody operated in the temperature range between -20 °C and 100 °C. We measured the normal spectral emissivity of alumina ceramic samples and determined the uncertainties. The combined standard relative uncertainties for the alumina samples at 100 °C was smaller than 1% when the emissivity was close to unity, and less than 3% when the emissivity was approximately 0.2.

A noncontact temperature measurement system applicable to a sub-micrometer scale area based on a thermoreflectance technique has been developed. A high spatial resolution of 0.7 µm is achieved using a 785 nm near-infrared laser and a confocal microscope. A relative change in the reflectivity of the order of 10-6 is detected without any data accumulation. A temperature resolution of 0.2 °C at around 100 °C is achieved for a molybdenum thin strip sample of 70 nm thickness and 100 µm width. The simultaneous measurements of thermal variations in the relative intensity of the reflected light and in electrical resistance enable us to calibrate the temperature scale of thermoreflectance thermometry.

This chapter describes the wide variety of experimental instrumentation and methods used for spectral emissivity measurements at both ambient and elevated temperatures, along with specific examples of materials studied. There are a number of measurement principles and methods to determine the spectral emissivity, because the emissivity can be defined by not only Planck's law but also Kirchhoff's law; the spectral emissivity depends on the direction of the emission, and the materials of interest are sometimes semitransparent or contaminated. The normal spectral emissivity of materials is of considerable interest for both practical and scientific reasons. The measurement methods for spectral emissivity are mainly categorized into two groups: (a) comparison between spectral radiation intensities measured from the sample and a blackbody, and (b) spectral reflectance measurements. Experimental difficulties that can be encountered in the spectral emissivity measurements at ambient temperatures are quite different from those at high temperatures. At high temperatures, it is particularly important to maintain or identify the physical and chemical conditions of the sample surfaces. Several experimental studies, using a variety of techniques, of solid and liquid metals and ceramics at ambient and high temperatures above 2000 °C are presented.

The next Japanese earth observing hyperspectral/multispectral imager mission, the HISUI (Hyper-spectral Imager SUIte) mission, is currently underway. In order to guarantee the hyperspectral images with a high spatial and wavelength resolution, it is necessary to evaluate the difference of the spectral sensitivities among the detector devices arrayed twodimensionally and correct spectral and spatial misregistrations and the effect of stray light. Since there are tens of thousands of detectors in the two-dimensional-array sensor, they have to be evaluated in parallel, instead of point by point, with the special technique for hyperspectral imagers. Hence, the new calibration system which has high radiance with the spatial uniformity and widely tunable wavelength range is required instead of conventional lamp systems which have poor power to calibrate arrayed devices at once. In this presentation, a supercontinuum-source-based system for calibration of hyperspectral imagers and its preliminary performance are described. Supercontinuum light is white light with continuous and broad spectra, which is generated by nonlinear optical effects of ultrashort pulse lasers in photonic crystal fibers. Using the system, the relative spectral responsivity and spectral misregistration of the hyperspectral imager, which is consist of a polychromator and twodimensionally arrayed CCD, are measured.

More and more NMIs are realizing their primary scale themselves with fixed-point blackbodies as their reference standard. However, commercially available fixed-point blackbody furnaces of sufficient quality are not always easy to obtain. CHINO Corp. and NMIJ, AIST jointly developed a new compact fixed-point blackbody furnace. The new furnace has such features as 1) improved temperature uniformity when compared to previous products, enabling better plateau quality, 2) adoption of the hybrid fixed-point cell structure with internal insulation to improve robustness and thereby to extend lifetime, 3) easily ejectable and replaceable heater unit and fixed-point cell design, leading to reduced maintenance cost, 4) interchangeability among multiple fixed points from In to Cu points. The replaceable cell feature facilitates long term maintenance of the scale through management of a group of fixed-point cells of the same type. The compact furnace is easily transportable and therefore can also function as a traveling standard for disseminating the radiation temperature scale, and for maintaining the scale at the secondary level and industrial calibration laboratories. It is expected that the furnace will play a key role of the traveling standard in the anticipated APMP supplementary comparison of the radiation thermometry scale.

We propose an efficient method of growing carbon nanotube (CNT) arrays on a variety of metals, alloys, and carbon materials using chemical vapor deposition (CVD) assisted by a simple surface treatment of the materials. The main feature of this method is the application of grit blasting with fine alumina particles to the development of a catalyst-support layer required for the growth of CNTs on various conductive materials, including ultra-hard metals such as tungsten. Auger electron spectroscopy shows that grit blasting can form a non-continuous layer where alumina nanoparticles are embedded as residues in the blasting media left on the treated surfaces. This work reveals that such a non-continuous alumina layer can behave as the catalyst-support layer, which is generally prepared by sputter or a vacuum evaporation coating process that considerably restricts the practical applications of CNTs. We have attempted to grow CNTs on grit-blasted substrates of eighteen conventionally used conductive materials using CVD together with a floating iron catalyst. The proposed method was successful in growing multi-walled CNT arrays on the grit-blasted surfaces of all the examined materials, demonstrating its versatility. Furthermore, we found that the group IV metal oxide films thermally grown on the as-received substrates can support the catalytic activity of iron nanoparticles in the CVD process just as well as the alumina film developed by grit blasting. Spectral emissivity of the CNT arrays in the visible and infrared wavelength ranges has been determined to assess the applicability of the CNT arrays as a black coating media.

In order to guarantee the observed data with high spatial and wavelength resolution of hyperspectral/multispectral imagers, it is necessary to evaluate the difference of the spectral sensitivity among the detector devices arrayed two-dimensionally and correct spectral and spatial misregistrations and the effect of stray light. However, there are tens of thousands of detectors in hyperspectral imagers, so they have to be evaluated in parallel by the special technique. Therefore, a light-source system which has high radiance with the spatial uniformity and widely tunable wavelength-range is required instead of the conventional lamp system. In this presentation, we report the new setup of the supercontinuum(SC)-source-monochromator system and its fundamental performance. The SC source covers a wavelength range of 450-2400 nm, and its total output power is up to 6 W. We effectively coupled a high-power SC laser to a single monochromator and obtained spatial uniformity through an integrating sphere or a relay-optics system. The radiance three or more magnitudes higher than a tungsten halogen lamp was measured with the supercontinuum-source based system. The stability of output power and the spatial uniformity of radiance at the integrating-sphere port were also evaluated. Using the system, spectral misregistrations and responsivities of a hyperspectral imager, which is consist of a polychromator and two-dimensional array of CCD, were measured.

High-temperature fixed points of metal-carbon systems, currently the target of a project in the international thermometry standards community, is also of high interest for pre-launch radiometric calibration of hyperspectral earth observing sensor in the blue wavelengths, where the conventional copper fixed point fails to supply sufficient radiance. For such a calibration, a fixed-point possibly around 2000 K is desired. One requirement for application of the high-temperature blackbody fixed-point cell to remote sensor calibration is to increase the radiating source aperture diameter to a size large enough to target with a radiance comparator based on a grating monochromator. In this presentation, a fixed-point cell of Co-C eutectic (1597 K) for remote sensor calibration application is described. An enlarged 7-mm aperture design is employed for the fixed-point cell while at the same time retaining the outer dimension to fit in existing fixed-point furnaces. The observed plateaux showed temperature and repeatability comparable to conventional 3-mm aperture cells, while cavity breakages indicates the need for improved robustness in the crucible design. Extension of the technique to Pt-C eutectic (2011 K) or Cr 3 C 2 -C peritectic (2100 K) systems, and subsequent application to calibration of the HISUI sensor is envisaged.

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.

Regular reflectance measurements of a forest of vertically aligned single-walled carbon nanotubes were made as a function of an incident angle for the S- and P-polarized lights in the infrared region. The low reflectance measured at normal incidence, 0.0005–0.0009, supports a model of a low material density and also the incident angle dependence of reflectance spectra for the S- and P-polarized lights suggests that the single-walled carbon nanotubes are highly anisotropic materials. These reflectance data, used in conjunction with an analysis of the Fresnel relations for anisotropic materials, permit optical constants to be obtained both parallel and perpendicular to the surface.

The National Measurement Institutes (NMIs) of the United States, Germany, France, Italy and Japan, have joined in an inter-laboratory comparison of their infrared spectral emittance scales. This action is part of a series of supplementary inter-laboratory comparisons (including thermal conductivity and thermal diffusivity) sponsored by the Consultative Committee on Thermometry (CCT) Task Group on Thermophysical Quantities (TG-ThQ). The objective of this collaborative work is to strengthen the major operative National Measurement Institutes' infrared spectral emittance scales and consequently the consistency of radiative properties measurements carried out worldwide. The comparison has been performed over a spectral range of 2 μm to 14 μm, and a temperature range from 23 °C to 800 °C. Artefacts included in the comparison are potential standards: oxidized Inconel, boron nitride, and silicon carbide. The measurement instrumentation and techniques used for emittance scales are unique for each NMI, including the temperature ranges covered as well as the artefact sizes required. For example, all three common types of spectral instruments are represented: dispersive grating monochromator, Fourier transform and filter-based spectrometers. More than 2000 data points (combinations of material, wavelength and temperature) were compared. Ninety-eight percent (98%) of the data points were in agreement, with differences to weighted mean values less than the expanded uncertainties calculated from the individual NMI uncertainties and uncertainties related to the comparison process. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The dc-operated infrared radiometer without a mechanical chopper has been developed and well characterized for blackbody radiation measurement near ambient temperature. The instrument has an excellent resolution of 5 mK in radiance temperature and a time-response of 0.1 s.

The nonlinearity characteristics of photoconductive and photovoltaic HgCdTe detectors were experimentally investigated in the infrared wavelength region by use of the National Physical Laboratory detector linearity measurement facility. The nonlinearity of photoconductive HgCdTe detectors was shown to be a function of irradiance rather than the total radiant power incident on the detector. Photoconductive HgCdTe detectors supplied by different vendors were shown to have similar linearity characteristics for wavelengths around 10 microm. However, the nonlinearity of response of a photovoltaic HgCdTe detector was shown to be significantly lower than the corresponding value for photoconductive HgCdTe detectors at the same wavelength.

Infrared radiometry requires large area, linear detectors of spatially uniform response. Currently the choice of high quality detectors of mid-infrared (>8 µm) radiation is far from ideal for radiometric applications. For example, HgCdTe detectors are widely used but exhibit very large (>20%) spatial non-uniformities in their responsivity whereas thermal detectors such as pyroelectric detectors have relatively low D* values. Quantum Well Infrared Photo-detectors (QWIPs) are now well established for use in state-of-the-art cooled thermal imaging systems, driven by military application. For fundamental optical measurement applications (for example, spectral responsivity standards) the expense and complication of imaging arrays is not required. Some QWIPs are made from layers of GaAs / AlxGa1-xAs material which can be mass grown on large substrate wafers with high spatial uniformity. As such, QWIPs offer the potential to be manufactured as a large area single pixel device, with a uniform spatial response, as well as a high D* value. This paper will detail the development of a single pixel QWIP detector and present the results of an initial evaluation of this detector, carried out at NPL.

We have developed high-speed infrared radiation thermometry techniques for measuring thermal diffusivity, thermal conductivity and specific heat capacity for solids with the laser flash method. Single- and multiple-element radiation thermometers have been constructed with an InSb detector which is cooled by liquid nitrogen and operated in dc-mode. Photovoltaic MCT (HgCdTe) thermometers also have been developed for near or sub-ambient temperature for a periodic heating method. The time response measured is fast enough up to 100 kHz or more. Calibrations for the temperature scale have been made for the range from 0/spl deg/C up to 200/spl deg/C within the accuracy of 0.2 K.

A Fourier‐transform infrared spectrometer (FTS) system for accurate measurement of thermal emission at low temperatures has been constructed. The FTS using a Michelson interferometer operated in vacuum covers the wavelength range between 5 μm and 12 μm with a mercury cadmium telluride detector. The FTS has been calibrated against a liquid‐nitrogen cooled cavity and a variable temperature cavity kept at 100 °C. A calibration formula using the advanced phase correction technique has been applied successfully. The calibrated spectra of the blackbody radiator in the temperature from −20 °C to 100 °C agree with the theoretical Planckian spectra within an average relative error of 0.6 % over the wavelength range. Additionally spectral‐emissivity measurements of metals with coated surfaces, glassy‐carbon, and silicon nitride ceramics have been performed as an application of the FTS in thermal measurements.

The effective emissivity of a cavity-type blackbody thermal radiator is greatly enhanced by a target disk with a coating of vertically aligned carbon nanotubes (CNT). The effective emissivity of this cavity is close to 1 and is less dependent on wavelength. Observed and calculated increases in radiance temperature owing to the use of the CNT disk show good agreement with each other and the dependence of the radiance temperature on the cavity depth is reduced substantially, thus enabling a compact cavity that can be effectively employed in the calibration of industrial radiation thermometers operating in a wide wavelength range.

The NRLM has developed a Fourier transform infrared spectrometer to measure spectral radiance of thermal-infrared emission near ambient temperatures with high accuracy. The spectrometer uses a simple Michelson interferometer that consists of corner cube mirrors and a KBr beam splitter. The spectral range between 5 (mu) m and 12 (mu) m was covered by a photovoltaic HgCdTe detector. For calibration and compensation for the offset drive, the spectrometer was equipped with two high quality reference blackbodies, a fixed-temperature blackbody cooled by liquid nitrogen and a variable temperature blackbody operated in the temperature range between -20$DEGC and 100$DEGC. The calibration procedure based on the advanced phase correction technique was applied to observed spectrum to complete reconstruction of the emission spectrum. Several tests were performed to check characteristics of the spectrometer. The results showed that the size-of-source effect (SSE) of the FTIR-spectrometer is negligibly small for a target larger than 20 mm diameter. We carried out an experiment to check the linearity between incident and measured spectral radiance inside the calibration levels by measuring the radiance from a third blackbody between -20$DEGC and 100$DEGC after calibration using the liquid nitrogen cooled blackbody and the fluid bath blackbody fixed at 100$DEGC. Observed non-linearity normalized at the blackbody radiance of 100$DEGC was smaller than the 0.5% around 10 (mu) m bands.

Two novel techniques of compensating for unknown distributed emissivity in temperature measurement by thermal imagers are presented. For both techniques the reflected image of a planar auxiliary source is superimposed on the thermal image of the object. In the first, the true temperature of the object is obtained by treating it as a blackbody when the radiance distribution, corresponding to emissivity pattern of the object, disappears. In the second, the reflectance ratio at two areas in the thermal image is utilized to compensate for emissivity. In this paper, principle of the emissivity compensation and preliminary test results are presented, and the procedures and their capabilities are demonstrated. The features of the schemes, such as elimination of the size-of-source effect, are discussed. The method is expected to become powerful tools for temperature distribution measurements in various applications, most notably the monitoring of local heat generation in highly-integrated or power electronic devices.