Flatness Improvement of Double-Sided Magnetic Film for Narrow Gap Electromagnetic Energy Harvester

Proceedings

Yoshii, Shinichi¹  Fujita, Takayuki²  Nakanishi, Ryosuke³ 

[1] Author to whom correspondence should be addressed.;Graduate School of Engineering, University of Hyogo, Himeji 671-2280, Japan;Presented at the Eurosensors 2018 Conference, Graz, Austria, 9–12 September 2018

关键词: MEMS;    energy harvester;    magnetic type;    NdFeB sputtering;    residual stress;   

DOI  :  10.3390/proceedings2131043

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

This paper reports the design, modeling and preliminary fabrication result of the flatness improved magnetic film on a silicon structure for narrow-gap electromagnetic (EMG) vibration energy harvester (VEH). The harvester has double-sided corrugated shape silicon vibration mass with 15 µm-thick NdFeB permanent magnet. The narrower air-gap between the magnetic film and a counter coil electrode the higher output power. While the sputtered magnetic film shows good characteristics equivalent to a bulk magnet, it hinders to reduce the air-gap because the silicon structure was curved by its high residual stress. Applying the double-sided magnet to our previous device, the curvature radius of moving mass with 15 µm-thick NdFeB film was improved from 5.3 m to 40.1 m because of the stress compensation. With the narrowed 2 µm air-gap device, the resulting simulated output power is 48 µW that is 190 times as large as previous device.

【 授权许可】

CC BY