提出一种压电效应和电磁效应相结合的微型能量采集器,基础结构为压电换能器(PZT)基八悬臂梁、长有Au线圈质量块、铷铁硼(Nd Fe B)永磁体。利用有限元分析软件ANSYS对微结构建立模型,通过结构力学特性分析,得到所设计结构的一阶谐振频率为214.7 Hz,为后期测试提供指导意义。制定微机电系统(MEMS)加工工艺流程,利用L-Edit软件设计并绘制所需掩模版。利用溶胶—凝胶(sol-gel)技术制备厚度为3 529 nm的PZT压电厚膜,实现了其与基底Pt/Ti/Si O2/Si/Si O2的良好异质集成,完成微型能量采集器制造过程中关键一步。经介电性能测试,PZT厚膜具有双蝴蝶状的极化反转峰,体现出较高的介电性能和耐压强度。400 k V/cm驱动条件下,测得PZT厚膜的电滞回线,其剩余极化强度Pr为37.7μC/cm2,矫顽场强为41.2 k V/cm,表现出良好的铁电性能。
A combination of piezoelectric effect and electromagnetic effect micro power generator is presented, of which the foundation structure is PZT-based eight cantilever beams, mass block with Au coil and NdFeB permanent magnets. The structural mechanic characteristic of the device is analyzed by finite element analysis software ANSYS. The first-order resonant frequency is estimated to be 214.7 Hz, pretty suggestive for the later test. The micromachining process is constituted and the mask layout of micro power generator is designed using L- Edit. Satisfactory heterogeneous integrated manufacturing of PZT piezoelectric films(3 529 nm)on the Pt/Ti/SiO2/ Si/SiO2 substrate is obtained with sol-gel technology, complete one key step in the whole producing process. The dielectric properties test show that PZT thick film has the double butterfly shape polarization reversal peak, high dielectric properties and compression strength. The electric hysteresis loop of PZT thick fiIm is measured in 400 kV/cm,which reveal good ferroelectric properties with residual polarization Pr(37.7 μC/cm2) and coercive field(41.2 kV/cm).