基于AlN-on-Si MEMS共振器的单结构3轴洛伦茨力磁力计
Cheng Tu1, Xu-Heng Ou-Yang1, Ying-Jie Wu1
1School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China.
Microsystems & nanoengineering
|May 10, 2024
概括
这项研究引入了使用AlN-on-Si MEMS共振器的新型3轴洛伦茨力磁力计 (LFM). 这种压电装置在环境压力下实现了灵敏的,多轴的磁场检测.
科学领域:
- 微电子机械系统 (MEMS) 是一种微电子机械系统.
- 传感器技术 传感器技术
- 固态物理 固态物理
背景情况:
- 传统的洛伦兹力磁表 (LFMs) 通常依赖于电容传感,这种传感可能受到寄生效应和操作条件的限制.
- 在一个单一的,紧的设备中实现多轴磁场传感提出了重大工程挑战.
研究的目的:
- 开发和描述一个单一结构的,3轴的洛伦兹力磁力计 (LFM) 使用压电AlN-on-Si MEMS振荡器.
- 为了证明在一个单一设备内使用不同的机械振动模式沿着三个直角轴测量磁场的能力.
- 提出一种新的等效电路模型,用于准确分析和分离洛伦茨力效应.
主要方法:
- 一个单一结构的AlN-on-Si MEMS共振器的制造.
- 在x轴和y轴磁场测量中激发外平面鼓式模式 (277 kHz).
- 在z轴磁场测量中激发平面内方形扩展模式 (5.4 MHz).
- 精确控制的激发电流的应用,用于模式激活和交叉干扰抑制.
- 开发和应用一种新的等效电路模型,以区分洛伦兹力信号与电容输入.
主要成果:
- 压电LFM成功地使用双机械模式测量了沿x,y和z轴的磁场.
- 获得的磁反应率为1.74 ppm/mT (x轴),1.83 ppm/mT (y轴) 和6.75 ppm/mT (z轴).
- 在轴之间表现出高灵敏度和良好的交叉干扰免疫力,与电容LFM相比.
- 相当的电路模型有效地将洛伦兹力效应与电容输入隔开.
结论:
- 展示的压电AlN-on-Si MEMS LFM为3轴磁场传感提供了可行的高灵敏度解决方案.
- 在单一结构中的双模式操作简化了设备设计并提高了性能.
- 这项技术对于需要在环境条件下进行紧,敏感的磁场测量应用具有前景.
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