Zhao Xiaofeng, Li Sen, Ai Chunpeng, Liu Hongmei, Wen Dianzhong
The Key Laboratory of Electronics Engineering, College of Heilongjiang Province, Heilongjiang University, Harbin 150080, China.
Micromachines (Basel). 2019 Mar 26;10(3):212. doi: 10.3390/mi10030212.
A novel piezoelectric energy harvester with multi-resonant frequencies based on Li-doped ZnO (LZO) thin films is proposed in this paper, consisting of an elastic element with three (or more) different length cantilever beam arrays and a piezoelectric structure (Al/Li-doped ZnO/Pt/Ti). The LZO thin films of piezoelectric structure were prepared on Pt/Ti/SiO₂/Si by using a radio frequency (RF) magnetron sputtering method under certain process conditions. When the LZO thin films were deposited with an LZO target concentration of 5 wt%, the piezoelectric coefficient was 9.86 pm/V. Based on this, the energy harvester chips were fabricated on a <100> silicon substrate using micro-electromechanical systems (MEMS) technology, and its performance can be measured by fixing it to a printed circuit board (PCB) test substrate. The experimental results show that, when exerting an external vibration acceleration of 2.2 g and a vibration frequency of 999 Hz, the energy harvester can achieve a big load voltage of 1.02 V at a load resistance of 600 kΩ, and a high load power of 2.3 µW at a load resistance of 200 kΩ.
本文提出了一种基于锂掺杂氧化锌（LZO）薄膜的具有多谐振频率的新型压电能量采集器，它由具有三个（或更多）不同长度悬臂梁阵列的弹性元件和压电结构（Al/Li掺杂ZnO/Pt/Ti）组成。采用射频（RF）磁控溅射法在一定工艺条件下在Pt/Ti/SiO₂/Si上制备了压电结构的LZO薄膜。当以5 wt%的LZO靶浓度沉积LZO薄膜时，压电系数为9.86 pm/V。在此基础上，利用微机电系统（MEMS）技术在<100>硅衬底上制造了能量采集器芯片，通过将其固定在印刷电路板（PCB）测试衬底上来测量其性能。实验结果表明，当施加2.2 g的外部振动加速度和999 Hz的振动频率时，能量采集器在600 kΩ的负载电阻下可实现1.02 V的大负载电压，在200 kΩ的负载电阻下可实现2.3 µW的高负载功率。
