Vacuum MEMS sensor based on thermopiles - simple model and experimental results

This paper presents a simple model of MEMS thermopile based vacuum detector and experimental results obtained for sensors designed and fabricated at IHTM-IMTM. Sensors contain two thermopiles, each with 30 multilayer p
⁺
Si/Al thermocouples and p
⁺
Si or Al heater. Thermal isolating membrane has sandwich structure consisting of sputtered SiO
2
and residual n-Si layer. Dependence of output thermopile voltage on pressure was measured for sensors with different membrane thickness. Tests were performed in pressure range (10
⁻³
−10
⁵
) Pa. Experimental results were compared with theoretical predictions.