可拉伸巨磁电阻磁场传感器的制备及其性能研究
发布时间：2018-11-16 17:36
【摘要】：相比于传统的硅基构件来说,柔性电子器件具有可拉伸、共形成型、弹性形变、轻便、不易破碎、加工效率高,成本低等诸多优点,已被广泛应用于弯曲显示屏、柔性电池、生物传感器和电子皮肤等各种领域。其中以磁性金属薄膜为基础的柔性磁电子器件与柔性自旋电子器件,因其可采用成熟的低温溅射镀膜工艺,且拥有优良的金属延展性以及灵敏可靠的对磁、电、热、应力等的多场响应的特点,在柔性电子领域内,具有重要的科研价值和广阔的应用前景。柔性磁电子薄膜的一个极其重要的应用是基于柔性磁性金属多层膜的磁场传感器,可以广泛应用于可穿戴的跟踪定位系统、电磁污染检测防护装置以及可植入式医疗设备等,是柔性可穿戴设备必不可少的重要组成部分。本论文针对基于聚二甲基硅氧烷(PDMS)超弹性有机衬底制备的可拉伸巨磁电阻磁场传感器展开研究。利用直流磁控溅射系统,在硅衬底上对自旋阀的结构进行优化。在对自旋阀结构优化之前,要对所用铁磁材料的工艺进行优化,以获得矫顽力较小,方形度好的铁磁金属薄膜,然后在FeCo/Cu/FeCo单自旋阀的基础上,获得了比较合适的非磁性金属层Cu的工艺参数,进而在单自由层的自旋阀结构中引入矫顽力较小的FeNi磁性薄膜,以降低自旋阀自由层的矫顽力,进而提高磁场传感器对外磁场反应的敏锐性。通过对自旋阀各层薄膜厚度的优化,最终获得的自旋阀结构,具有高的磁电阻率、高的磁场灵敏度、较低的自由层矫顽力,较低的饱和场。在柔性衬底上制备自旋阀结构,并对其进行应力调控研究。将获得的具有优异综合性能的自旋阀结构生长在柔性衬底上,使用条形掩膜板和曲形掩膜板来减少薄膜裂纹的产生,通过预应变的方法,获得具有自组装周期性褶皱结构的柔性自旋阀器件,将应力集中释放在衬底上,这样就有效地避免了应力各向异性导致的不利影响,从而获得了磁场灵敏度在较大拉伸形变下能够保持稳定的自旋阀磁场传感器。制备的可拉伸自旋阀巨磁电阻磁场传感器的拉伸范围达50%,且具有很好的稳定性,疲劳测试说明器件具有很好的抗疲劳特性。利用曲形掩膜板和预拉伸制备的自旋阀器件,由于在释放过程中应力的产生,导致金属薄膜出现裂纹,进而导致器件失效,所以,曲形掩膜板的方法在制备拉伸范围较大的自旋阀薄膜器件上受到限制。
[Abstract]:Compared with traditional silicon based components, flexible electronic devices have many advantages, such as tensile, co-forming, elastic deformation, lightweight, not easily broken, high processing efficiency, low cost and so on, and have been widely used in bending display screen, flexible battery, etc. Biosensors and electronic skin and other fields. Among them, flexible magnetoelectronic devices and flexible spin electronic devices based on magnetic metal thin films, because they can adopt mature low temperature sputtering coating technology, have excellent metal ductility and sensitive and reliable magnetic, electrical and thermal properties. The characteristics of multi-field response of stress and so on have important scientific research value and broad application prospect in the field of flexible electronics. One of the most important applications of flexible magnetoelectronic thin films is the magnetic field sensor based on flexible magnetic metal multilayer film, which can be widely used in wearable tracking and positioning systems, electromagnetic pollution detection and protection devices, implantable medical devices, etc. It is an essential part of flexible wearable devices. In this paper, the extensible giant magnetoresistance magnetic field sensor based on polydimethylsiloxane (PDMS) superelastic organic substrate is studied. The structure of spin valve was optimized on silicon substrate by DC magnetron sputtering system. Before optimizing the structure of spin valve, the process of ferromagnetic material should be optimized to obtain ferromagnetic metal film with small coercivity and good square degree, and then on the basis of FeCo/Cu/FeCo single spin valve. The process parameters of non-magnetic metal layer (Cu) are obtained, and FeNi magnetic thin films with low coercivity are introduced into the spin valve structure of single free layer to reduce the coercivity of the free layer of spin valve. Furthermore, the sensitivity of magnetic field sensor to external magnetic field response is improved. By optimizing the thickness of each layer of spin valve, the structure of spin valve has high magnetic resistivity, high magnetic sensitivity, low free layer coercivity and low saturation field. Spin valve structure was prepared on flexible substrate and its stress regulation was studied. The spin-valve structure with excellent comprehensive performance is grown on the flexible substrate. The strip mask and curved mask are used to reduce the cracks in the film. A flexible spin valve device with self-assembled periodic fold structure is obtained, and the stress concentration is released on the substrate, which effectively avoids the adverse effect caused by the stress anisotropy. Thus, a spin valve magnetic field sensor with stable magnetic field sensitivity under large tensile deformation is obtained. The tensile range of the tensile spin-valve giant magnetoresistive magnetic field sensor is 50 and has good stability. The fatigue test shows that the device has good fatigue resistance. The spin-valve device fabricated by curved mask and pretension leads to cracks in the metal film due to the stress generated during the release process, which leads to the failure of the device. The method of curved mask plate is limited in the fabrication of spin valve thin film devices with large stretching range.
【学位授予单位】：浙江理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212
本文编号：2336174
[Abstract]:Compared with traditional silicon based components, flexible electronic devices have many advantages, such as tensile, co-forming, elastic deformation, lightweight, not easily broken, high processing efficiency, low cost and so on, and have been widely used in bending display screen, flexible battery, etc. Biosensors and electronic skin and other fields. Among them, flexible magnetoelectronic devices and flexible spin electronic devices based on magnetic metal thin films, because they can adopt mature low temperature sputtering coating technology, have excellent metal ductility and sensitive and reliable magnetic, electrical and thermal properties. The characteristics of multi-field response of stress and so on have important scientific research value and broad application prospect in the field of flexible electronics. One of the most important applications of flexible magnetoelectronic thin films is the magnetic field sensor based on flexible magnetic metal multilayer film, which can be widely used in wearable tracking and positioning systems, electromagnetic pollution detection and protection devices, implantable medical devices, etc. It is an essential part of flexible wearable devices. In this paper, the extensible giant magnetoresistance magnetic field sensor based on polydimethylsiloxane (PDMS) superelastic organic substrate is studied. The structure of spin valve was optimized on silicon substrate by DC magnetron sputtering system. Before optimizing the structure of spin valve, the process of ferromagnetic material should be optimized to obtain ferromagnetic metal film with small coercivity and good square degree, and then on the basis of FeCo/Cu/FeCo single spin valve. The process parameters of non-magnetic metal layer (Cu) are obtained, and FeNi magnetic thin films with low coercivity are introduced into the spin valve structure of single free layer to reduce the coercivity of the free layer of spin valve. Furthermore, the sensitivity of magnetic field sensor to external magnetic field response is improved. By optimizing the thickness of each layer of spin valve, the structure of spin valve has high magnetic resistivity, high magnetic sensitivity, low free layer coercivity and low saturation field. Spin valve structure was prepared on flexible substrate and its stress regulation was studied. The spin-valve structure with excellent comprehensive performance is grown on the flexible substrate. The strip mask and curved mask are used to reduce the cracks in the film. A flexible spin valve device with self-assembled periodic fold structure is obtained, and the stress concentration is released on the substrate, which effectively avoids the adverse effect caused by the stress anisotropy. Thus, a spin valve magnetic field sensor with stable magnetic field sensitivity under large tensile deformation is obtained. The tensile range of the tensile spin-valve giant magnetoresistive magnetic field sensor is 50 and has good stability. The fatigue test shows that the device has good fatigue resistance. The spin-valve device fabricated by curved mask and pretension leads to cracks in the metal film due to the stress generated during the release process, which leads to the failure of the device. The method of curved mask plate is limited in the fabrication of spin valve thin film devices with large stretching range.
【学位授予单位】：浙江理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212
【参考文献】
相关期刊论文 前10条
1 肖敏;于晓东;;基于巨磁电阻的高精度方向盘转角传感器研究[J];电子世界;2015年22期
2 TOK Jeffrey B.-H.;;Recent advances in flexible and stretchable electronics, sensors and power sources[J];Science China(Chemistry);2012年05期
3 靳惠莹;李华;;磁光克尔效应及其应用[J];教育教学论坛;2011年35期
4 李文涛;谢致薇;杨元政;陈先朝;;薄膜巨磁电阻效应及其研究进展[J];材料导报;2010年15期
5 刘鹏;;基于自旋阀结构的磁传感器的研究[J];中国集成电路;2008年12期
6 王永进;兰中文;余忠;郑飞雁;;GMR生物传感器的原理及研究现状[J];微纳电子技术;2007年Z1期
7 蔡建旺;;磁电子学器件应用原理[J];物理学进展;2006年02期
8 颜冲,于军,包大新,陈文洪,朱大中;自旋电子学研究进展[J];固体电子学研究与进展;2005年01期
9 都有为;纳米材料中的巨磁电阻效应[J];物理学进展;1997年02期
10 蔡建旺,赵见高,詹文山,沈保根;磁电子学中的若干问题[J];物理学进展;1997年02期
相关博士学位论文 前1条
1 刘华瑞;自旋阀结构及GMR传感器研究[D];清华大学;2006年
，本文编号：2336174
本文链接：https://www.wllwen.com/kejilunwen/zidonghuakongzhilunwen/2336174.html
