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Gerhard Ulm - One of the best experts on this subject based on the ideXlab platform.
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The PTB high-accuracy Spectral Responsivity scale in the VUV and x-ray range
Metrologia, 2006Co-Authors: Alexander Gottwald, U. Kroth, Mathias Richter, Frank Scholze, Michael Krumrey, Gerhard UlmAbstract:At the electron storage ring BESSY II, the Physikalisch-Technische Bundesanstalt operates ten experimental stations at six synchrotron radiation beamlines for photon metrology in the Spectral range from ultraviolet radiation to x-rays. Five of these beamlines are used to realize and disseminate a scale of Spectral Responsivity for photodetectors. Detector calibration is based on the use of cryogenic radiometers as primary detector standards. The current status of instrumentation and measurement capabilities is described. Best measurement capabilities (k = 2) for the calibration of photodiodes vary between 0.4% and 2.3%.
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The PTB high-accuracy Spectral Responsivity scale in the ultraviolet
Metrologia, 2000Co-Authors: Mathias Richter, U. Johannsen, U. Kroth, P. Kuschnerus, Gerhard Ulm, Hans Rabus, L. WernerAbstract:The Physikalisch-Technische Bundesanstalt (PTB) has established Spectral Responsivity standards for photodetectors in the wavelength range between 200 nm and 400 nm based on cryogenic electrical-substitution radiometers. In order to obtain standards over a continuous wavelength range with low uncertainty, combined use is made of both the dispersed synchrotron radiation of the storage ring BESSY I and quasi-monochromatic laser radiation. Taking advantage of the specific properties of the monochromatized synchrotron radiation and the laser radiation, relative standard uncertainties between 10−3 and 5 × 10−3 are achieved in the calibration of trap detectors in the Spectral range 400 nm to 200 nm.
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Determination of the electron–hole pair creation energy for semiconductors from the Spectral Responsivity of photodiodes
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 1999Co-Authors: Frank Scholze, P. Kuschnerus, Mathias Richter, Hans Rabus, H. Henneken, Gerhard UlmAbstract:Abstract Ionizing radiation can be detected by the measurement of the charge carriers produced in a detector. The improved semiconductor technology now allows detectors operating near the physical limits of the detector materials to be designed. The mean energy required for producing an electron–hole pair, W , is a material property of the semiconductor. Here, the determination of W from the Spectral Responsivity of photodiodes is demonstrated. Using Spectrally dispersed synchrotron radiation, different types of semiconductor photodiodes have been examined in the UV-, VUV-, and soft X-ray Spectral range. Their Spectral Responsivity was determined with relative uncertainties between 0.4% and 1% using a cryogenic electrical-substitution radiometer as primary detector standard. Results are presented for silicon n-on-p junction photodiodes and for GaAsP/Au Schottky diodes at room temperature. The investigations for silicon covered the complete Spectral range from 3 to 1500 eV, yielding a constant value W =(3.66±0.03) eV for photon energies above 50 eV, a maximum value of W =4.4 eV at photon energies around 6 eV, and a linear relation W = hν (one electron per photon) for photon energies below 4 eV. For GaAsP, we obtained a constant value of W =4.58 eV in the photon energy range from 150 to 1500 eV, with a relative uncertainty of 1–3%, depending on the photon energy.
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PtSi–n–Si Schottky‐barrier photodetectors with stable Spectral Responsivity in the 120–250 nm Spectral range
Applied Physics Letters, 1996Co-Authors: K. Solt, H. Melchior, U. Kroth, P. Kuschnerus, V. Persch, H. Rabus, Mathias Richter, Gerhard UlmAbstract:Front‐illuminated PtSi–n–Si Schottky barrier photodiodes have been developed for the ultraviolet and vacuum ultraviolet Spectral range. Their Spectral Responsivity was determined in the 120–500 nm Spectral range by use of a cryogenic electrical substitution radiometer operated with Spectrally dispersed synchrotron radiation. For wavelengths below 250 nm, the Spectral Responsivity is about 0.03 A/W, comparable to that of GaAsP Schottky photodiodes. Unlike the GaAsP diodes, the new PtSi–n–Si diodes have a spatially uniform response which is virtually stable after prolonged exposure to short wavelength radiation. Even after a radiant exposure of 150 mJ cm−2 at wavelength 120 nm, the relative reduction in Spectral Responsivity remains below 0.2%. Due to these features, this type of photodiode is a promising candidate for use as secondary detector standard in the ultraviolet and vacuum ultraviolet Spectral ranges.
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ptsi n si schottky barrier photodetectors with stable Spectral Responsivity in the 120 250 nm Spectral range
Applied Physics Letters, 1996Co-Authors: K. Solt, H. Melchior, U. Kroth, P. Kuschnerus, V. Persch, H. Rabus, Mathias Richter, Gerhard UlmAbstract:Front‐illuminated PtSi–n–Si Schottky barrier photodiodes have been developed for the ultraviolet and vacuum ultraviolet Spectral range. Their Spectral Responsivity was determined in the 120–500 nm Spectral range by use of a cryogenic electrical substitution radiometer operated with Spectrally dispersed synchrotron radiation. For wavelengths below 250 nm, the Spectral Responsivity is about 0.03 A/W, comparable to that of GaAsP Schottky photodiodes. Unlike the GaAsP diodes, the new PtSi–n–Si diodes have a spatially uniform response which is virtually stable after prolonged exposure to short wavelength radiation. Even after a radiant exposure of 150 mJ cm−2 at wavelength 120 nm, the relative reduction in Spectral Responsivity remains below 0.2%. Due to these features, this type of photodiode is a promising candidate for use as secondary detector standard in the ultraviolet and vacuum ultraviolet Spectral ranges.
Lutz Werner - One of the best experts on this subject based on the ideXlab platform.
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The CCPR K2.c key comparison of Spectral Responsivity from 200 nm to 400 nm
Metrologia, 2014Co-Authors: Lutz WernerAbstract:The CCPR K2.c key comparison of Spectral Responsivity from 200 nm to 400 nm was carried out in the framework of the CIPM Mutual Recognition Arrangement by 14 participating national metrology institutes. The key comparison was piloted by the Physikalisch-Technische Bundesanstalt (PTB). The comparison principle, measurements, analysis and results including a procedure to deal with the issue of inconsistent data are described.
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Calibration and interpolation of the Spectral Responsivity of silicon photodiode-based detectors
Sensors and Actuators A: Physical, 2009Co-Authors: Lutz Werner, Jürgen HartmannAbstract:The Spectral Responsivity of optical detectors is widely required in photometry, radiometry, and thermometry to absolutely measure the optical output of sources and the amount of optical radiation received at surfaces. Absolute calibration of the Spectral Responsivity requires a direct traceability to SI units. The method of traceable calibration of the Spectral Responsivity with very low uncertainties at the Physikalisch-Technische Bundesanstalt, the national metrology institute of Germany, is described for both, the experimental procedure and the subsequent mathematical analysis of the obtained measured values together with a statement of the uncertainty.
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Analytical model for the temperature dependence of the Spectral Responsivity of silicon
Journal of the Optical Society of America B, 2001Co-Authors: J. Hartmann, J. Fischer, U. Johannsen, Lutz WernerAbstract:An analytical theory based on a model of the internal quantum efficiency of the silicon photodiode and the temperature dependence of the absorption coefficient of silicon is developed to predict the temperature dependence of the Spectral Responsivity in the wavelength range from 400 to 1020 nm near room temperature. The influence of the various parameters of the model on the temperature coefficient is investigated theoretically. Comparison of measurements and prediction shows good agreement. The developed model permits further improvement of accuracy in Spectral-Responsivity scales based on silicon photodiodes, especially in the near-infrared wavelength region.
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Accurate determination of the Spectral Responsivity of silicon trap detectors between 238 nm and 1015 nm using a laser-based cryogenic radiometer
Metrologia, 2000Co-Authors: Lutz Werner, J. Fischer, U. Johannsen, J. T. HartmannAbstract:The Physikalisch-Technische Bundesanstalt has further improved and extended its Spectral Responsivity scale based on the laser-operated radiation thermometry cryogenic radiometer. Five laser wavelengths in the ultraviolet (UV) (238 nm to 400 nm) and another fifteen in the visible and near-infrared (NIR) (400 nm to 1015 nm) almost cover the entire Spectral range where silicon photodiodes can be used in air. The lasers employed are a Kr+ laser, an Ar+ laser with optional intra-cavity frequency-doubling, and a continuously tuneable Ti:sapphire ring laser. The total relative standard uncertainty of the Spectral Responsivity at the laser lines is u = 10-4 in the visible and NIR below 950 nm and u = 10-3 in the UV. With an improved model for interpolation between the laser wavelengths, a continuous scale of Spectral Responsivity has been established in the wavelength range 400 nm to 1015 nm.
Mathias Richter - One of the best experts on this subject based on the ideXlab platform.
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Bilateral NIST?PTB comparison of Spectral Responsivity in the VUV
Metrologia, 2011Co-Authors: Alexander Gottwald, Mathias Richter, Ping-shine Shaw, Uwe ArpAbstract:To compare the calibration capabilities for the Spectral Responsivity in the vacuum-ultraviolet Spectral region between 135 nm and 250 nm, PTB and NIST agreed on a bilateral comparison. Calibrations of semiconductor photodiodes as transfer detectors were performed using monochromatized synchrotron radiation and cryogenic electrical substitution radiometers as primary detector standards. Great importance was attached to the selection of suitable transfer detector standards due to their critical issues in that wavelength regime. The uncertainty budgets were evaluated in detail. The comparison showed a reasonable agreement between the participants. However, it became obvious that the uncertainty level for this comparison cannot easily be further reduced due to the lack of sufficiently radiation-hard and long-term stable transfer standard detectors. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCPR-WGKC.
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The PTB high-accuracy Spectral Responsivity scale in the VUV and x-ray range
Metrologia, 2006Co-Authors: Alexander Gottwald, U. Kroth, Mathias Richter, Frank Scholze, Michael Krumrey, Gerhard UlmAbstract:At the electron storage ring BESSY II, the Physikalisch-Technische Bundesanstalt operates ten experimental stations at six synchrotron radiation beamlines for photon metrology in the Spectral range from ultraviolet radiation to x-rays. Five of these beamlines are used to realize and disseminate a scale of Spectral Responsivity for photodetectors. Detector calibration is based on the use of cryogenic radiometers as primary detector standards. The current status of instrumentation and measurement capabilities is described. Best measurement capabilities (k = 2) for the calibration of photodiodes vary between 0.4% and 2.3%.
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The PTB high-accuracy Spectral Responsivity scale in the ultraviolet
Metrologia, 2000Co-Authors: Mathias Richter, U. Johannsen, U. Kroth, P. Kuschnerus, Gerhard Ulm, Hans Rabus, L. WernerAbstract:The Physikalisch-Technische Bundesanstalt (PTB) has established Spectral Responsivity standards for photodetectors in the wavelength range between 200 nm and 400 nm based on cryogenic electrical-substitution radiometers. In order to obtain standards over a continuous wavelength range with low uncertainty, combined use is made of both the dispersed synchrotron radiation of the storage ring BESSY I and quasi-monochromatic laser radiation. Taking advantage of the specific properties of the monochromatized synchrotron radiation and the laser radiation, relative standard uncertainties between 10−3 and 5 × 10−3 are achieved in the calibration of trap detectors in the Spectral range 400 nm to 200 nm.
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Determination of the electron–hole pair creation energy for semiconductors from the Spectral Responsivity of photodiodes
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 1999Co-Authors: Frank Scholze, P. Kuschnerus, Mathias Richter, Hans Rabus, H. Henneken, Gerhard UlmAbstract:Abstract Ionizing radiation can be detected by the measurement of the charge carriers produced in a detector. The improved semiconductor technology now allows detectors operating near the physical limits of the detector materials to be designed. The mean energy required for producing an electron–hole pair, W , is a material property of the semiconductor. Here, the determination of W from the Spectral Responsivity of photodiodes is demonstrated. Using Spectrally dispersed synchrotron radiation, different types of semiconductor photodiodes have been examined in the UV-, VUV-, and soft X-ray Spectral range. Their Spectral Responsivity was determined with relative uncertainties between 0.4% and 1% using a cryogenic electrical-substitution radiometer as primary detector standard. Results are presented for silicon n-on-p junction photodiodes and for GaAsP/Au Schottky diodes at room temperature. The investigations for silicon covered the complete Spectral range from 3 to 1500 eV, yielding a constant value W =(3.66±0.03) eV for photon energies above 50 eV, a maximum value of W =4.4 eV at photon energies around 6 eV, and a linear relation W = hν (one electron per photon) for photon energies below 4 eV. For GaAsP, we obtained a constant value of W =4.58 eV in the photon energy range from 150 to 1500 eV, with a relative uncertainty of 1–3%, depending on the photon energy.
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PtSi–n–Si Schottky‐barrier photodetectors with stable Spectral Responsivity in the 120–250 nm Spectral range
Applied Physics Letters, 1996Co-Authors: K. Solt, H. Melchior, U. Kroth, P. Kuschnerus, V. Persch, H. Rabus, Mathias Richter, Gerhard UlmAbstract:Front‐illuminated PtSi–n–Si Schottky barrier photodiodes have been developed for the ultraviolet and vacuum ultraviolet Spectral range. Their Spectral Responsivity was determined in the 120–500 nm Spectral range by use of a cryogenic electrical substitution radiometer operated with Spectrally dispersed synchrotron radiation. For wavelengths below 250 nm, the Spectral Responsivity is about 0.03 A/W, comparable to that of GaAsP Schottky photodiodes. Unlike the GaAsP diodes, the new PtSi–n–Si diodes have a spatially uniform response which is virtually stable after prolonged exposure to short wavelength radiation. Even after a radiant exposure of 150 mJ cm−2 at wavelength 120 nm, the relative reduction in Spectral Responsivity remains below 0.2%. Due to these features, this type of photodiode is a promising candidate for use as secondary detector standard in the ultraviolet and vacuum ultraviolet Spectral ranges.
Dong-hoon Lee - One of the best experts on this subject based on the ideXlab platform.
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Spectral Responsivity measurement of photovoltaic detectors by comparison with a pyroelectric detector on individual nano-second laser pulses
Metrologia, 2017Co-Authors: Keesuk Hong, Seongchong Park, Jisoo Hwang, Errol Atkinson, P. Manson, Dong-hoon LeeAbstract:We demonstrate that the individual single pulse of a nano-second laser can be used to measure the Spectral Responsivity of photovoltaic detectors. With this new scheme, the relative Spectral Responsivity of a photodiode can be determined from the Spectral reflectance of the surface of a pyroelectric detector. We also developed the adequate data acquisition procedure, which can eliminate systematic errors caused by the nonlinear pulse response. The method is experimentally demonstrated for Si and Ge photodiodes in a wide wavelength range from 420 nm to 1600 nm and verified by comparison with the method using a CW source.
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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, Dong-hoon 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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Realization of the Spectral Responsivity scale based on an absolute cryogenic radiometer
Journal of the Korean Physical Society, 2015Co-Authors: Keesuk Hong, Seongchong Park, Seung-kwan Kim, Seung-nam Park, Dong-hoon LeeAbstract:We present the concept of and the procedure for realizing the primary scale of the Spectral Responsivity based on an absolute cryogenic radiometer at the Korea Research Institute of Standards and Science (KRISS). A detailed error and uncertainty analysis is performed by calibrating the standard detectors in the wavelength range from 300 nm to 1000 nm. The relative expanded uncertainty of the Spectral Responsivity calibration for a Si trap detector is 0.06% at 632.8 nm and 0.4% for other wavelengths ( k = 2). The calibration results are validated by comparing with the results from a theoretical model of quantum efficiency for a transmission-type trap detector.
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Measurement of relative Spectral Responsivity of photovoltaic detectors by using single tunable pulsed laser
2015 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2015Co-Authors: Keesuk Hong, Seongchong Park, Dong-hoon Lee, Jisoo HwangAbstract:We describe a novel method to measure the relative Spectral Responsivity of Si and Ge photovoltaic detectors from 250 nm to 1700 nm based on a tunable nano-second pulsed optical parametric oscillator (OPO).
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REALIZATION OF THE Spectral Responsivity SCALE IN KRISS
2006Co-Authors: Dong-hoon Lee, Dong-joo Shin, Seung-kwan KimAbstract:Korea Research Institute of Standards and Science (KRISS) realizes the Spectral Responsivity scale using a laser-based absolute cryogenic radiometer (ACR) as the primary standard. The ACR calibrates Si trap detectors, which serve as the working standards disseminating the scale through direct comparison. Outside the calibrated wavelength range of the trap detectors, a pyroelectric detector is used as the transfer standard. We present the recently renovated apparatus setup for establishing and maintaining the Spectral Responsivity scale in KRISS, as well as the measured characteristics of the new working standards.
J. T. Hartmann - One of the best experts on this subject based on the ideXlab platform.
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New PTB Setup for the Absolute Calibration of the Spectral Responsivity of Radiation Thermometers
International Journal of Thermophysics, 2008Co-Authors: K. Anhalt, A. Zelenjuk, D. R. Taubert, T. Keawprasert, J. T. HartmannAbstract:The paper describes the new experimental setup assembled at the PTB for the absolute Spectral Responsivity measurement of radiation thermometers. The concept of this setup is to measure the relative Spectral Responsivity of the radiation thermometer using the conventional monochromator-based Spectral comparator facility also used for the calibration of filter radiometers. The absolute Spectral Responsivity is subsequently measured at one wavelength, supplied by the radiation of a diode laser, using the new setup. The radiation of the diode laser is guided with an optical fiber into an integrating sphere source that is equipped with an aperture of absolutely known area. The Spectral radiance of this integrating sphere source is determined via the Spectral irradiance measured by a trap detector with an absolutely calibrated Spectral Responsivity traceable to the primary detector standard of the PTB, the cryogenic radiometer. First results of the Spectral Responsivity calibration of the radiation thermometer LP3 are presented, and a provisional uncertainty budget of the absolute Spectral Responsivity is given.
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Improved calibration of the Spectral Responsivity of interference filter radiometers in the visible and near infrared Spectral range at PTB
Metrologia, 2003Co-Authors: D. R. Taubert, J. T. Hartmann, R. Friedrich, Jörg HollandtAbstract:At the Physikalisch-Technische Bundesanstalt (PTB) silicon diode-based narrow-band interference filter radiometers (FR) are used for the radiometric determination of thermodynamic temperatures. To extend the temperature range down to 400 °C, the centre wavelength of the FRs was shifted from the visible to the near infrared (900 nm, 1000 nm and 1595 nm). An improved calibration procedure is presented which achieves relative uncertainties for the Spectral Responsivity of the FRs of the order of 10−4, by taking into consideration the increased temperature coefficient of the Spectral Responsivity and the nonlinearity of the silicon detectors when operated in the near infrared wavelength region.
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Accurate determination of the Spectral Responsivity of silicon trap detectors between 238 nm and 1015 nm using a laser-based cryogenic radiometer
Metrologia, 2000Co-Authors: Lutz Werner, J. Fischer, U. Johannsen, J. T. HartmannAbstract:The Physikalisch-Technische Bundesanstalt has further improved and extended its Spectral Responsivity scale based on the laser-operated radiation thermometry cryogenic radiometer. Five laser wavelengths in the ultraviolet (UV) (238 nm to 400 nm) and another fifteen in the visible and near-infrared (NIR) (400 nm to 1015 nm) almost cover the entire Spectral range where silicon photodiodes can be used in air. The lasers employed are a Kr+ laser, an Ar+ laser with optional intra-cavity frequency-doubling, and a continuously tuneable Ti:sapphire ring laser. The total relative standard uncertainty of the Spectral Responsivity at the laser lines is u = 10-4 in the visible and NIR below 950 nm and u = 10-3 in the UV. With an improved model for interpolation between the laser wavelengths, a continuous scale of Spectral Responsivity has been established in the wavelength range 400 nm to 1015 nm.
