Novel MEMS power generator with integrated thermoelectric and vibrational devices

This paper describes a novel concept of an integrated power generator chip that utilizes environmental temperature differences and vibrations as power sources. In the concept, thermoelectric devices produce voltage by the Seebeck effect and vibrational devices produce electrostatic energy from the external kinetic energy of vibration. A monolithic fabrication process for these microelectromechanical systems (MEMS) devices is proposed based on the seamless integration technology (SeaiT) consisting of thick-film forming processes with deep reactive ion etching (DRIE) of Si, electroplating of gold and ashing of a sacrificial layer. The fabricated thermoelectric devices generated its voltage outputs under temperature difference. The vibrational devices were also evaluated by applying an ac voltage which showed its resonant frequency characteristics. The integration of the different types of power generation paves the way for utilizing small amounts of energy from human and environmental sources.