Temperature measurements and multi-physical field simulations of micro-sized metal film bridge

• This sensor measures between 300 K and 1500 K with a spatial resolution of 125 μm.
• The maximum deviation between simulations and experiments is 7.6%.
• Results verify the reliability of the measuring method and the simulations.
• The critical ignition current was evaluated as 182 mA for MFB with lead styphnate.

To measure the temperature of micro-sized metal film bridge under constant current excitations, by the Fabry–Perot interferometric technology, a new optical fiber sensor was designed for high temperature measurements and quick temperature response. A matched spectrum demodulation system was independently designed and manufactured, including advantage such as a response frequency up to 1.5–5 kHz, wide measuring range between ambient temperature and 1500 K, and sensor spatial resolution of 125 μm. For comparison, the temperature distributions under different current excitation values were obtained by multi-physical field simulations. Experimental values and simulation results have a maximum deviation of 7.6%, indicating the reliability and credibility of the results. In addition, the critical ignition current was evaluated as 182 mA, for the micro-sized metal film bridge charged with lead styphnate. The self-designed optical fiber Fabry–Perot sensor provides effective techniques for ignition safety and reliability, when used for precise temperature measurements of micro zones. Furthermore, it is of vital importance to assess the electrothermal conversion efficiency of heating devices in micro-electromechanical system.