Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
737208 | Sensors and Actuators A: Physical | 2014 | 7 Pages |
•Electrostatic energy harvesting with variable gap.•MEMS energy harvester with fully packaging.•Compatible fabrication process with wireless sensor networks.
In this paper, we report on an electrostatic energy harvester with an out-of-the-plane gap closing scheme. Using advanced MEMS technology, energy harvesting devices formed by a four wafer stack are batch fabricated and fully packaged at wafer scale. A spin coated CYTOP polymer is used both as an electret material and an adhesive layer for low temperature wafer bonding. The overall size of the device is about 1.1 cm × 1.3 cm. At an external load resistance of 13.4 MΩ, a power output of 0.15 μW is achieved when vibration at an acceleration amplitude of 1 g (∼9.8 m/s2) is applied at a low frequency of 96 Hz. The frequency response of the device is also measured and a broader bandwidth is observed at higher acceleration amplitude.