C2.2 - Energy Harvesting for Wireless Autonomous Sensor Systems
- SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
- Proceedings SENSOR 2011
- C2 - Energy Harvesting
- R. von Schaijk - Holst Centre - Stichting IMEC, KN Eindhoven (Netherlands)
- 391 - 396
The rapidly growing need for energy autonomy of wireless sensor nodes can be only well served by using various energy harvesting technologies in combination with energy storage devices. The market acceptance of such solutions necessitates further cost reduction, which can be achieved by taking advantage of MEMS technology.
This paper focuses on the principle and technology development for piezoelectric and thermoelectric harvesting devices within imec / Holst Centre. An overview of the latest results will be given.
The vacuum packaged miniature piezoelectric harvester (<1 cm3) delivers a maximum power output of about 100 mW for an acceleration of 1.0 g. The piezo material is AlN, chosen for its good figure of merit for energy harvesting and its relative easy processing. The importance of vacuum packaged wafer level packaging for maximum power output and reliability will be shown.
The micromachined thermoelectric harvester yields an open-circuit voltage of 1.2 V for a temperature difference of 20 °C. Further improvement is approached respectively by improving optimizing the material properties.