【摘要】：相比于傳統(tǒng)的硅基構件來說,柔性電子器件具有可拉伸、共形成型、彈性形變、輕便、不易破碎、加工效率高,成本低等諸多優(yōu)點,已被廣泛應用于彎曲顯示屏、柔性電池、生物傳感器和電子皮膚等各種領域。其中以磁性金屬薄膜為基礎的柔性磁電子器件與柔性自旋電子器件,因其可采用成熟的低溫濺射鍍膜工藝,且擁有優(yōu)良的金屬延展性以及靈敏可靠的對磁、電、熱、應力等的多場響應的特點,在柔性電子領域內,具有重要的科研價值和廣闊的應用前景。柔性磁電子薄膜的一個極其重要的應用是基于柔性磁性金屬多層膜的磁場傳感器,可以廣泛應用于可穿戴的跟蹤定位系統(tǒng)、電磁污染檢測防護裝置以及可植入式醫(yī)療設備等,是柔性可穿戴設備必不可少的重要組成部分。本論文針對基于聚二甲基硅氧烷(PDMS)超彈性有機襯底制備的可拉伸巨磁電阻磁場傳感器展開研究。利用直流磁控濺射系統(tǒng),在硅襯底上對自旋閥的結構進行優(yōu)化。在對自旋閥結構優(yōu)化之前,要對所用鐵磁材料的工藝進行優(yōu)化,以獲得矯頑力較小,方形度好的鐵磁金屬薄膜,然后在FeCo/Cu/FeCo單自旋閥的基礎上,獲得了比較合適的非磁性金屬層Cu的工藝參數(shù),進而在單自由層的自旋閥結構中引入矯頑力較小的FeNi磁性薄膜,以降低自旋閥自由層的矯頑力,進而提高磁場傳感器對外磁場反應的敏銳性。通過對自旋閥各層薄膜厚度的優(yōu)化,最終獲得的自旋閥結構,具有高的磁電阻率、高的磁場靈敏度、較低的自由層矯頑力,較低的飽和場。在柔性襯底上制備自旋閥結構,并對其進行應力調控研究。將獲得的具有優(yōu)異綜合性能的自旋閥結構生長在柔性襯底上,使用條形掩膜板和曲形掩膜板來減少薄膜裂紋的產生,通過預應變的方法,獲得具有自組裝周期性褶皺結構的柔性自旋閥器件,將應力集中釋放在襯底上,這樣就有效地避免了應力各向異性導致的不利影響,從而獲得了磁場靈敏度在較大拉伸形變下能夠保持穩(wěn)定的自旋閥磁場傳感器。制備的可拉伸自旋閥巨磁電阻磁場傳感器的拉伸范圍達50%,且具有很好的穩(wěn)定性,疲勞測試說明器件具有很好的抗疲勞特性。利用曲形掩膜板和預拉伸制備的自旋閥器件,由于在釋放過程中應力的產生,導致金屬薄膜出現(xiàn)裂紋,進而導致器件失效,所以,曲形掩膜板的方法在制備拉伸范圍較大的自旋閥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.
【學位授予單位】：浙江理工大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TP212

【參考文獻】

相關期刊論文 前10條

1 肖敏;于曉東;;基于巨磁電阻的高精度方向盤轉角傳感器研究[J];電子世界;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 靳惠瑩;李華;;磁光克爾效應及其應用[J];教育教學論壇;2011年35期

4 李文濤;謝致薇;楊元政;陳先朝;;薄膜巨磁電阻效應及其研究進展[J];材料導報;2010年15期

5 劉鵬;;基于自旋閥結構的磁傳感器的研究[J];中國集成電路;2008年12期

6 王永進;蘭中文;余忠;鄭飛雁;;GMR生物傳感器的原理及研究現(xiàn)狀[J];微納電子技術;2007年Z1期

7 蔡建旺;;磁電子學器件應用原理[J];物理學進展;2006年02期

8 顏沖,于軍,包大新,陳文洪,朱大中;自旋電子學研究進展[J];固體電子學研究與進展;2005年01期

9 都有為;納米材料中的巨磁電阻效應[J];物理學進展;1997年02期

10 蔡建旺,趙見高,詹文山,沈保根;磁電子學中的若干問題[J];物理學進展;1997年02期

相關博士學位論文 前1條

1 劉華瑞;自旋閥結構及GMR傳感器研究[D];清華大學;2006年

，

本文編號：2336174