A Novel Multi-Source Micro Power Generator for Harvesting Thermal and Optical Energy

Abstract

A novel multi-source micro power generator for harvesting thermal and optical energy is proposed for the first time. The fabrication of the power generator is compatible with complementary metal-oxide-semiconductor transistor technology. The device consists of a micro thermoelectric generator (μ-TEG) and a solar cell on a single chip. In order to optimize the heat flux path of the device, the two ends of the thermopile are insulated by the polyimide thermal insulating layer and oxide passivation layer. To improve the performance of the solar cell, the oxide passivation layer is perforated with limited metal contact openings and interdigitated poly-Si electrodes are adopted. The measured results show that if the liquid metal thermal grease covers the top side of the device, the maximum output voltage factor and power factor of the μ-TEG are 0.316 Vcm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> and 6.34×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> μWcm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> , respectively. When the top and bottom sides of the device are chosen as the light-receiving surfaces, the measured efficiencies of the solar cell are 4.11% and 0.5%, respectively. In practical use, measuring electrodes on the same side and vertical injected/ejected heat flux path allow for convenient package.