Multifunctional Integrated Sensors for Multiparameter Monitoring Applications

We present multifunctional integrated sensors (MFISES) that combine temperature, humidity, pressure, air speed, chemical gas, magnetic, and acceleration sensing on a single 2-mm × 2-mm die. We fabricate the MFISES in a wafer scale encapsulation process to hermetically seal the sensor functions with moving parts at low vacuum, and then surface micromachine the environmental sensors on top of the sealed layer. The encapsulation process provides very stable conditions for the pressure, magnetic, and acceleration sensors, and enables the deployment of the MFISES in dynamic environmental conditions without special postprocess packaging. We quantify the performance requirements for sensor applications in weather stations, indoor climate control, road activity monitoring, chemical sensing, and parking monitoring. We compare the performance of the MFISES to the application requirements to demonstrate the utility of an integrated sensor in a wide range of applications.