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M. Klonz - One of the best experts on this subject based on the ideXlab platform.

  • Explanation for the AC–DC Voltage Transfer Differences in Thin-Film Multijunction Thermal Converters on Silicon Chips at High Frequencies
    IEEE Transactions on Instrumentation and Measurement, 2007
    Co-Authors: L. Scarioni, M. Klonz, E. Kessler
    Abstract:

    In this paper, an explanation for the ac-dc voltage transfer differences at frequencies greater than 100 kHz of the standard thin-film or planar multijunction Thermal Converter (PMJTC) developed at the Physikalisch-Technische Bundesanstalt and fabricated on a silicon chip has been found. The simulation indicates that the capacitance of the bond pads of the heater is the reason for an increase of the ac-dc voltage transfer difference of PMJTCs with higher heater resistance to negative values. Bond pads of smaller size and larger distance are shown to improve the frequency response

  • quartz planar multijunction Thermal Converter as a new ac dc current transfer standard up to 1 mhz
    Conference on Precision Electromagnetic Measurements, 2004
    Co-Authors: L. Scarioni, M. Klonz, T Funck
    Abstract:

    The new generation of PMJTCs on quartz membranes and on quartz crystal chips developed at the PTB results in new ac-dc current transfer standards for the current of 10 mA and the frequency range from 10 kHz to 1 MHz, accompanied with small uncertainties. For a PMJTC with a heater resistance of 240 Omega the uncertainties for frequencies up to 100 kHz are smaller than 1 muA/A and up to 1 MHz they increase to 5 muA/A (k=1). A model for the PMJTC has been developed which allows calculating the ac-dc current transfer difference as well as the attributed uncertainties. The agreement of the simulation and the measurement were tested for high heater resistances of 700 Omega and 240 Omega, for which quite large ac-dc differences are calculated. The good agreement validates the model

  • High-frequency thin-film multijunction Thermal Converter on a quartz crystal chip
    IEEE Transactions on Instrumentation and Measurement, 2003
    Co-Authors: L. Scarioni, H. Laiz, M. Klonz, D. Janik, Marian Kampik
    Abstract:

    The design of a new planar or thin-film multijunction Thermal Converter (PMJTC) on a quartz membrane and a quartz crystal chip results in a calculable standard for AC-DC voltage transfer for frequencies from 100 kHz to 100 MHz with improved uncertainties. This is due to smaller dielectric losses and higher insulation resistance in the quartz membrane and the quartz chip. The window with the membrane is anisotropically etched into the quartz crystal chip. For the first measurements, the temperature of the heater was radiometrically sensed with a thin-film infrared sensor and later with an array of 100 Cu-CuNi thermocouples. At frequencies higher than 100 kHz, the AC-DC voltage transfer differences are one order smaller than with the standard PMJTC with the Si/sub 3/N/sub 4//SiO/sub 2//Si/sub 3/N/sub 4/ sandwich membrane on a silicon chip.

  • dynamic non linear electro Thermal simulation of a thin film Thermal Converter
    Microelectronics Journal, 1999
    Co-Authors: H. Laiz, M. Klonz
    Abstract:

    Abstract This article describes the electro-Thermal simulation of the ac–dc transfer differences at low frequencies of a thin-film Thermal Converter. The dynamic non-linear model includes the temperature dependence of all the material parameters, and the radiation losses. It is used to optimise the performance of the device at low frequencies, where temperature oscillations are present due to the lack of integration of the oscillating Joule heat. The results of the simulation are compared with those of the measurements using a digital method.

  • AC-DC Thermal Converter with infrared-transmissive fiber coupling
    IEEE Transactions on Instrumentation and Measurement, 1999
    Co-Authors: Fred L. Katzmann, M. Klonz
    Abstract:

    AC-DC Thermal Converters are fabricated by depositing thin-film heaters on thin dielectric membranes on a silicon chip and by remotely sensing their temperature with radiation sensors through infrared transmissive fibers. This permits all degrees of freedom for the design of the heater for optimum frequency response. In the present design the sensitivity is quite small. With a temperature of the heater 100 K above ambient, only 5 /spl mu/W heats up the black spot target of the radiation sensor, resulting in an output voltage of 1.5 mV. The standard deviation of the mean of an AC-DC voltage transfer involving 12 measurements is approximately 20/spl times/10/sup -6/ to 50/spl times/10/sup -6/.

Yasutaka Amagai - One of the best experts on this subject based on the ideXlab platform.

  • Low-Frequency AC–DC Differences of a Series–Parallel Circuit of Thermal Converters
    IEEE Transactions on Instrumentation and Measurement, 2019
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Kenjiro Okawa, Nobuhisa Kaneko
    Abstract:

    A series–parallel connected Thermal Converter (TC) arranged in an $m \times m$ matrix of a heater and an $m^{2}$ -series connected thermocouple are proposed to reduce low-frequency ac–dc differences. The electrical circuit theory on the proposed circuit suggests that the low-frequency ac–dc differences of $m \times m$ series–parallel connected TCs decrease in proportion to 1/ $m^{2}$ , avoiding any degradation in the output voltage and a time-consuming measurement. A significant reduction of the low-frequency ac–dc differences by a factor of 10 for the proposed circuit is experimentally demonstrated with no decrease of the output voltage, which is consistent with the electrical circuit theory.

  • ac dc transfer technique for measuring thomson coefficient toward thermoelectric metrology
    IEEE Transactions on Instrumentation and Measurement, 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Atsushi Yamamoto, Megumi Akoshima, Nobuhisa Kaneko
    Abstract:

    We introduce an ac/dc transfer technique for measuring the Thomson coefficient of a metallic sample in high-temperature thermoelectric metrology. The Thomson coefficient is measured by applying equivalent dc and ac to a metallic wire configured similarly to a single-junction Thermal Converter that is widely used in ac/dc transfer devices. The use of ac/dc makes the expression of the Thomson coefficient simpler than in conventional methods. We describe the measurement principle, the design of the measurement setup, and the experimental results in detail. The experimental results agree closely with those obtained from using a conventional method.

  • Thermal-Converter Validation of Differential Sampling Measurement Based on AC-Programmable Josephson Voltage Standard System
    2015 15th International Superconductive Electronics Conference (ISEC), 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, H Yamamori, Michitaka Maruyama, Chiharu Urano, S.-f. Chen, N.-h. Kaneko
    Abstract:

    This paper describes a differential sampling measurement system using AC-programmable Josephson voltage standard (AC-PJVS) system up to 10 V in the frequency range down to 1 Hz. Such system combines the versatility and the accuracy and stability of the Josephson voltage standard. The validity of this method is confirmed with the AC-DC difference measurements of a calibrated Thermal Converter, and with an electro-Thermal simulation at the root-mean square amplitudes of 3 V. The uncertainty of our differential sampling measurement system is estimated to be 1.3 μV/V for waveform frequencies of 62.5 Hz and root-mean square amplitude of 10 V.

  • Improvements in the Low-Frequency Characteristic and Sensitivity of a Thin-Film Multijunction Thermal Converter in Vacuum
    IEEE Transactions on Instrumentation and Measurement, 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Koji Shimizume, Kaname Kishino, Shigeru Hidaka
    Abstract:

    We have improved the ac-dc transfer differences and enhanced the sensitivity in our thin-film multijunction Thermal Converters (TFMJTCs) in vacuum. The ac-dc transfer differences of the TFMJTCs are less than 1 $\mu $ V/V down to 1 Hz and 10 $\mu $ V/V down to 0.2 Hz owing to the increased Thermal time constant. The measured output voltage exceeds 120 mV at $10^{\mathrm {-4}}$ Pa owing to the reduction of heat conduction to the air. The sensitivity of the device, defined as the ratio of the output voltage to the input power, is 2.4 V/W, which is approximately three times larger than that measured at ambient pressure. Numerical simulations of the heat transfer of our TFMJTC explain the experimental results well.

  • Improved ElectroThermal Simulation for Low-Frequency Characterization of a Single-Junction Thermal Converter
    IEEE Transactions on Instrumentation and Measurement, 2014
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki
    Abstract:

    We perform a numerical simulation for the low-frequency characterization of a single-junction Thermal Converter down to 1 Hz using an improved electroThermal model. The low-frequency characterization of a Thermal Converter below 10 Hz is of great importance for linking ac-dc transfer standards and low-frequency ac voltage standards based on sampling methods. One feature of our model is the incorporation of the heat capacity for the thermocouple, which has previously been neglected to reproduce an accurate Thermal time constant. Our model also includes the temperature dependence of the Seebeck coefficient in the thermocouple in addition to the temperature-dependent material parameters of the heater. To verify the simulation results, the calculated results are compared with the experimental results, which shows that our improved model well reproduces the measured data below 1 Hz. The estimated uncertainty of the simulated ac-dc transfer differences is 49 μV/V at 4 Hz. These results suggest that our model is a useful predictive tool at low frequencies.

H. Laiz - One of the best experts on this subject based on the ideXlab platform.

  • Fabrication of a thin-film Thermal Converter with resistive sensing
    CPEM 2010, 2010
    Co-Authors: L. Di Lillo, L. Malatto, Gustavo Giménez, E. Mangano, L. Fraigi, H. Laiz
    Abstract:

    A new thin-film Thermal Converter was designed and constructed. It senses the temperature rise of the heater using resistors made of vanadium oxide (V02). This paper presents details of the fabrication process and materials selection.

  • High-frequency thin-film multijunction Thermal Converter on a quartz crystal chip
    IEEE Transactions on Instrumentation and Measurement, 2003
    Co-Authors: L. Scarioni, H. Laiz, M. Klonz, D. Janik, Marian Kampik
    Abstract:

    The design of a new planar or thin-film multijunction Thermal Converter (PMJTC) on a quartz membrane and a quartz crystal chip results in a calculable standard for AC-DC voltage transfer for frequencies from 100 kHz to 100 MHz with improved uncertainties. This is due to smaller dielectric losses and higher insulation resistance in the quartz membrane and the quartz chip. The window with the membrane is anisotropically etched into the quartz crystal chip. For the first measurements, the temperature of the heater was radiometrically sensed with a thin-film infrared sensor and later with an array of 100 Cu-CuNi thermocouples. At frequencies higher than 100 kHz, the AC-DC voltage transfer differences are one order smaller than with the standard PMJTC with the Si/sub 3/N/sub 4//SiO/sub 2//Si/sub 3/N/sub 4/ sandwich membrane on a silicon chip.

  • dynamic non linear electro Thermal simulation of a thin film Thermal Converter
    Microelectronics Journal, 1999
    Co-Authors: H. Laiz, M. Klonz
    Abstract:

    Abstract This article describes the electro-Thermal simulation of the ac–dc transfer differences at low frequencies of a thin-film Thermal Converter. The dynamic non-linear model includes the temperature dependence of all the material parameters, and the radiation losses. It is used to optimise the performance of the device at low frequencies, where temperature oscillations are present due to the lack of integration of the oscillating Joule heat. The results of the simulation are compared with those of the measurements using a digital method.

  • AC voltage Converter module with thin-film Multijunction Thermal Converter
    Conference Digest Conference on Precision Electromagnetic Measurements, 1
    Co-Authors: B. Stojanovic, M. Klonz, H. Laiz
    Abstract:

    An ac module for a dc multimeter has been designed around the Planar Multijunction Thermal Converter (PMJTC) to measure ac voltage by automatic ac-dc transfer for frequencies from 10 Hz up to 1 MHz. The electronic uses the standard PMJTC in an isoThermal way. It applies the sum of the ac signal and the dc feedback at the same time directly to one heater. The dc therefore is an accurate measure for the ac quantity. With this design the time for an accurate ac-dc transfer is reduced considerably.

Hiroyuki Fujiki - One of the best experts on this subject based on the ideXlab platform.

  • Low-Frequency AC–DC Differences of a Series–Parallel Circuit of Thermal Converters
    IEEE Transactions on Instrumentation and Measurement, 2019
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Kenjiro Okawa, Nobuhisa Kaneko
    Abstract:

    A series–parallel connected Thermal Converter (TC) arranged in an $m \times m$ matrix of a heater and an $m^{2}$ -series connected thermocouple are proposed to reduce low-frequency ac–dc differences. The electrical circuit theory on the proposed circuit suggests that the low-frequency ac–dc differences of $m \times m$ series–parallel connected TCs decrease in proportion to 1/ $m^{2}$ , avoiding any degradation in the output voltage and a time-consuming measurement. A significant reduction of the low-frequency ac–dc differences by a factor of 10 for the proposed circuit is experimentally demonstrated with no decrease of the output voltage, which is consistent with the electrical circuit theory.

  • ac dc transfer technique for measuring thomson coefficient toward thermoelectric metrology
    IEEE Transactions on Instrumentation and Measurement, 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Atsushi Yamamoto, Megumi Akoshima, Nobuhisa Kaneko
    Abstract:

    We introduce an ac/dc transfer technique for measuring the Thomson coefficient of a metallic sample in high-temperature thermoelectric metrology. The Thomson coefficient is measured by applying equivalent dc and ac to a metallic wire configured similarly to a single-junction Thermal Converter that is widely used in ac/dc transfer devices. The use of ac/dc makes the expression of the Thomson coefficient simpler than in conventional methods. We describe the measurement principle, the design of the measurement setup, and the experimental results in detail. The experimental results agree closely with those obtained from using a conventional method.

  • Thermal-Converter Validation of Differential Sampling Measurement Based on AC-Programmable Josephson Voltage Standard System
    2015 15th International Superconductive Electronics Conference (ISEC), 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, H Yamamori, Michitaka Maruyama, Chiharu Urano, S.-f. Chen, N.-h. Kaneko
    Abstract:

    This paper describes a differential sampling measurement system using AC-programmable Josephson voltage standard (AC-PJVS) system up to 10 V in the frequency range down to 1 Hz. Such system combines the versatility and the accuracy and stability of the Josephson voltage standard. The validity of this method is confirmed with the AC-DC difference measurements of a calibrated Thermal Converter, and with an electro-Thermal simulation at the root-mean square amplitudes of 3 V. The uncertainty of our differential sampling measurement system is estimated to be 1.3 μV/V for waveform frequencies of 62.5 Hz and root-mean square amplitude of 10 V.

  • Improvements in the Low-Frequency Characteristic and Sensitivity of a Thin-Film Multijunction Thermal Converter in Vacuum
    IEEE Transactions on Instrumentation and Measurement, 2015
    Co-Authors: Yasutaka Amagai, Hiroyuki Fujiki, Koji Shimizume, Kaname Kishino, Shigeru Hidaka
    Abstract:

    We have improved the ac-dc transfer differences and enhanced the sensitivity in our thin-film multijunction Thermal Converters (TFMJTCs) in vacuum. The ac-dc transfer differences of the TFMJTCs are less than 1 $\mu $ V/V down to 1 Hz and 10 $\mu $ V/V down to 0.2 Hz owing to the increased Thermal time constant. The measured output voltage exceeds 120 mV at $10^{\mathrm {-4}}$ Pa owing to the reduction of heat conduction to the air. The sensitivity of the device, defined as the ratio of the output voltage to the input power, is 2.4 V/W, which is approximately three times larger than that measured at ambient pressure. Numerical simulations of the heat transfer of our TFMJTC explain the experimental results well.

  • Improved Stability of Thin-Film Multijunction Thermal Converters
    Electrical Engineering in Japan, 2014
    Co-Authors: Yasutaka Amaga, Hiroyuki Fujiki, Koji Shimizume, Shigeru Hidaka
    Abstract:

    SUMMARY We have demonstrated the long-term stability and environmental durability of a high-performance thin-film multijunction Thermal Converter (TMJTC) with an improved thin-film thermopile design. We fabricated a new TMJTC with an improved deposition pattern for a Bi-Sb-Cu-based thin-film thermopile in order to avoid interface delamination between the Bi and the Cu layers. Our TMJTC exhibited good frequency properties, with an ac–dc difference of less than 5 μV/V in the range from 10 Hz to 100 kHz, at a root-mean-square (rms) voltage of 10 V. The long-term stability of the TMJTC has been significantly increased owing to the performance of the developed thin-film thermopile, as compared with that of previously fabricated TMJTCs, exhibiting an ac–dc difference of less than 2 μV/V after 18 months at room temperature. We also evaluated the temperature, relative humidity, and pressure characteristics of the TMJTC in accordance with the International Electrotechnical Commission (IEC) standards for electronic devices. The measurement results showed that the dependence of the ac–dc transfer difference on the temperature, humidity, and pressure was less than 1 μV/V, which is comparable to the results of Thermal Converters, constituting the primary standard.

T. Weimann - One of the best experts on this subject based on the ideXlab platform.