Integration of a low frequency, tunable MEMS piezoelectric energy harvester and a thick film micro capacitor as a power supply system for wireless sensor nodes

This work presents an integration approach towards manufacturing a MEMS piezoelectric vibration energy harvester and an electrochemical capacitor on the same substrate. Vibration energy harvesters have been fabricated to resonate at low frequencies, matching ambient vibrations found abundantly in buildings. For cost-effective resonance tuning, a direct write dispenser printer can be used to print additional mass at the tips of the beams, and is also used to deposit a capacitor in the open space surrounding the beam. The implementation of a power supply on a single platform is of great value especially for autonomous wireless sensors with long lifetime and small device volume requirements.