Kim Hyun-Uk, Lee Woo-Ho, Dias H V Rasika, Priya Shashank
Center for Energy Harvesting Materials and Systems (CEHMS), Materials Science and Engineering, Virginia Tech, Blacksburg, VA, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2009 Aug;56(8):1555-68. doi: 10.1109/TUFFC.2009.1220.
This manuscript reviews the developments made in design and fabrication of piezoelectric microgenerators and presents a method for making a comparative study within various vibration energy harvesting mechanisms. Current generation vibration energy harvesters have power density in the range of 0.8 microW/mm3. The manuscript also reports our results on synthesis of barium titanate (BT) thin films for MEMS (micro-electromechanical systems) based energy harvester. BT sol-gel was synthesized by aqueous process using barium acetate and titanium bis (ammonium lacto) dihydroxide with PVP (Polyvinylpyrrolidone). After optimizing the annealing temperature and time, textured BT films with 600 nm thickness were obtained on (111) Pt/Ti/SiO2 wafer. A MEMS fabrication process flow was designed to produce microcantilever chips from BT films constituting 6 cantilevers connected in series with an interdigital electrode pattern. We also present some concepts for further improvement of the power density of vibration energy harvesters by incorporating 3-D structure, magnetoelectric material, and a multimodal scheme.
本文综述了压电微发电机在设计和制造方面取得的进展，并提出了一种在各种振动能量收集机制中进行比较研究的方法。当前的振动能量收集器的功率密度在0.8微瓦/立方毫米范围内。本文还报告了我们基于MEMS（微机电系统）的能量收集器用钛酸钡（BT）薄膜合成的结果。通过使用醋酸钡和二氢氧化二（铵乳）钛与PVP（聚乙烯吡咯烷酮）的水溶液法合成了BT溶胶 - 凝胶。在优化退火温度和时间后，在（111）Pt/Ti/SiO₂晶片上获得了厚度为600纳米的织构化BT薄膜。设计了一种MEMS制造工艺流程，以由构成6个串联的带有叉指电极图案的悬臂梁的BT薄膜制造微悬臂梁芯片。我们还提出了一些通过结合三维结构、磁电材料和多模态方案来进一步提高振动能量收集器功率密度的概念。
