Magnetostatic detection using magnetoresistive sensors with vertical motion flux modulation.
Magnetostatic detection using magnetoresistive sensors with vertical motion flux modulation.
复制标题
DOI：
10.1063/1.4723823
复制
发表时间：
2012-05
期刊：
影响因子：
--
通讯作者：
Jiafei Hu;M. Pan;Wugang Tian;Dixiang Chen;Jianqiang Zhao
中科院分区：
文献类型：
--
作者：
Jiafei Hu;M. Pan;Wugang Tian;Dixiang Chen;Jianqiang Zhao
近年来，磁链调制技术被用来解决磁阻传感器的1/f噪声问题。然而，大多数磁通调制方案与简单的微机电系统（MEMS）致动器的效率还不能令人满意。为了提高调制效率，本文提出了垂直运动磁通调制（VMFM）。在VMFM中，由MEMS致动器驱动的软磁膜在具有一对磁通集中器的MR传感器上方垂直振动。因此，检测到的静磁场被调制到1/f噪声低得多的较高频率。研制了基于多层巨磁阻传感器AA 002的VMFM样机，其磁通调制效率达到18.7%，超过了其他方案的效率。此外，静磁检测能力提高到530 pT/kHz。
Recently, the flux modulation has been presented to deal with the 1/f noise of magnetoresistive (MR) sensors. However, the efficiency of most flux modulation schemes with simple micro- electromechanical-system (MEMS) actuators is not satisfying yet. In this paper, the vertical motion flux modulation (VMFM) is proposed to improve the modulation efficiency. In VMFM, the soft magnetic film driven by a MEMS actuator vibrates vertically above the MR sensors with a pair of flux concentrators. Consequently, the detected magnetostatic field is modulated to the higher frequency where the 1/f noise is much lower. A VMFM prototype based on AA002 (multi-layered giant magnetoresistive sensors) was fabricated and its flux modulation efficiency can reach 18.7%, which exceeds most achieved efficiency with other schemes. Also, the magnetostatic detection ability is improved to 530 pT/√Hz.