Advances in Radio Science www.adv-radio-sci.net 1684-9965 1684-9973 6 Kleinheubacher Berichte 2007 2008 10.5194/ars-6-31-2008 http://www.adv-radio-sci.net/6/31/2008/ http://www.adv-radio-sci.net/6/31/2008/ars-6-31-2008.html http://www.adv-radio-sci.net/6/31/2008/ars-6-31-2008.pdf 31 34 2008-05-26 A torsional sensor for MEMS-based RMS voltage measurements J. Dittmer j.dittmer@tu-bs.de R. Judaschke S. Büttgenbach Institute for Microtechnology, Technische Universität Braunschweig, Germany Physikalisch-Technische Bundesanstalt, Braunschweig, Germany RF voltage measurement based on electrostatic RMS voltage-to-force conversion is an alternative method in comparison to the conventional thermal power dissipation method. It is based on a mechanical force induced by an RF voltage applied to a micro-mechanical system. For a theoretically adequate resolution and high precision measurements, the necessary geometrical dimensions of the sensor require the application of micro machining. In this contribution, the dependence between electrical and geometrical properties of different sensor designs is investigated. Based on these results, problems related to practical micro-machining and solutions with respect to possible sensor realizations are discussed. The evolution of different sensor generations is shown. Bartek, M., Xiao, Z., van Mullem, C., and Wolffenbuttel, R.: Bulk-micromachined electrostatic RMS-to-DC converter: Design and fabrication, in: Tech. digest MME 2000, 1–3 October, Uppsala, Sweden, p. A14, 2000. Beissner, S., Wogersien, A., Buttgenbach, S., Schrader, T., and Stumper, U.: Micromechanical device for the measurement of the RMS value of high-frequency voltages, Sensors, 2003, Proc. IEEE, 1, 631–635, 2003. Dittmer, J., Judaschke, R., and Büttgenbach, S.: Aufbau und Charakterisierung eines mikro-elektromechanischen Torsionssensors für die Hochfrequenzspannungsmessung, in: Mikrosystemtechnik Kongress 2007, Dresden, pp. 775–758, VDE Verlag GmbH, 2007a. Dittmer, J., Judaschke, R., and Büttgenbach, S.: A Miniaturized RMS Voltage Sensor Based on a Torsional Actuator in Bulk Silicon Technology, pp. 769–770, Micro- and Nano Engineering, Kopenhagen, 2007b. Fernandez, L J., Visser, E., Sese, J., Wiegerink, R., Jansen, H., Flokstra, J., and Elwenspoek, M.: Radio frequency power sensor based on MEMS technology, Proc. IEEE Sensors, pp. 549–552, 2003. Sattler, R., Plötz, F., Fattinger, G., and Wachutka, G.: Modeling of an electrostatic torsional actuator: demonstrated with an RF MEMS switch, Sensors and Actuators A, 97–98, 337–346, 2002.