Experimental Characterization of a Double-Spiral Resistive Temperature Microsensor

This paper describes an experimental characterization of a planar double-spiral resistive temperature microsensor. The proposed microsensor has been fabricated by means of a thermal evaporation process by employing a 1.2 mm-thick borofloat glass substrate and by depositing a 100 nm-thick aluminum (Al) layer stacked between two 20 nm-thick chromium (Cr) layers. The fabricated microsensor has a track width of 50 µm with an inter-track spacing of approximately 300 µm. The experimental characterization has been performed by means of a tailored PID controlled temperature chamber including two Peltier cells, two fans and a Pt100 resistive temperature detector (RTD) for temperature control and monitoring. A sensitivity of 1.2 Ω/°C in the considered temperature range of 16 – 66 °C has been achieved showing a maximum nonlinearity error of 0.41 % referred to the span. The obtained experimental results confirm the possibility to exploit the proposed microsensor for temperature measurements.