| Zugriffsnummer | 16196 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | AC-DC voltage transfer standards with thin-film multijunction thermal converters and planar resistors |
| Autor(in); Institution |
Klonz, Manfred; 2.1, Gleichstrom und Niederfrequenz, PTB-Braunschweig
Laiz, Hector; Instituto Nacional de Tecnologia Industrial (INTI), San Martin, ARGENTINA
Kessler, Ernst; Institut für Physikalische Hochtechnologie e. V. (IPHT), Jena, GERMANY
Scarioni, Luciana; 2.1, Gleichstrom und Niederfrequenz, PTB-Braunschweig; Universidad de Carabobo, Facultad de Ciencias y Tecnologia, Valencia, VENEZUELA
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| Quelle/Jahr | Spectrum of metrology: from the state-of-the-art to the everyday : NCSL International annual workshop and symposium, Tampa, [August 17 - 21, 2003] ; conference proceedings 2003:(2003) |
| Availability | [CD-ROM] ; file name: 4E-2.pdf |
| ISBN | 1-584-64041-3 |
| Verlag | Boulder, Colo.: NCSL International |
| Konferenzangaben | NCSL International Annual Workshop and Symposium, Tampa, Fla., 17-21, August, 2003, USA |
| Zusammenfassung | This paper discusses recent results of ac-dc voltage standards with thin-film multijunction thermal converters (PMJTC) and planar serial resistors for the frequency range from 10 Hz up to 1 MHz and for the voltage range from 100 mV to 1000 V. The standard PTB/IPHT PMJTC is well established and fabricated on a silicon chip with a thin dielectric membrane on an anisotropically etched window in the silicon. A thin-film bifilar heater and up to 100 thermocouples are sputtered on a low-stress Si3N4 membrane. A small obelisk of silicon is left underneath the heater during the etching process to increase the thermal time-constant. The voltage coefficient is the main source for the ac-dc transfer differences at frequencies below 100 Hz. It is correlated with the power coefficient of the sensitivity. Some tools to compensate the power coefficient were investigated. An optimum compensation is achieved with thermocouples from CuNi44/BiSbTe. Capacitances in the heater area, the loss factor of the membrane, the residual conductance of the silicon underneath the membrane, and skin effect in the leads are the main causes for the ac-dc transfer differences increasing to higher frequencies. A tradeoff was found with a heater resistance of 190 Ω at which the different effects compensate each other. The design of a new generation of PMJTCs on quartz membranes and on quartz crystal chips improves the frequency response. For the serial high voltage resistors from 100 V to 1000 V new planar resistors with negligible voltage dependence have been fabricated on AIN substrates. |
