摘要
随着吸波材料在微波通信抗电磁辐射以及电子对抗等领域中的广泛应用以Ｆｅ基
可３实现微波的宽频带吸收而日益受到人们的重视牌价
因而在吸波材料研究中提出了对该类薄膜磁谱进行测量的紧迫要求
make的用法在对国内外薄膜复磁导率测量方法进行比较分析的基础上
以一般传输线方程为基础
又从Ｍａｘｗｅｌｌ方程组出发
最后通过网络分析仪测出样品放置前后短路微带线的反射系数
运用高频结构仿真软件Ansoft-HFSS设计了短路微带结构测试夹具
在线日语学习
直观地验证了测量方法的可行性
加上自行设计的短路微带腔
采用ＧＰＩＢ总线结构搭建了一个薄膜磁导率测量系统大大提高了测试效率
µ的ＦｅＣｏ基薄膜样品在０．５
厚度为0.4m
结果基本可靠
测试装置简单并且计算简单
不需要采用迭代法求解方程
该方法既适合于面内各向同性纳米膜磁导率的测量
关键词
ABSTRACT
With the widespread u of wave-absorbing materials in the field such as microwave communication, microwave darkroom, electromagnetic antiradiation, electronic countermeasure, it become an important problem to rearch and develop wave-absorbing materials answering the abo
ve demand. FeCo-bad alloy nano-granular films and nano-multilayer films are much accounted for their high permeability and high loss under microwave frequency to realize broadband absorbing of microwave. The exact knowledge µ is esntial in the study of stealthy material. So the measurem ent of film permeability
r
of complex permeability of thin films at microwave frequencies is very important.
Microstrip reflection method was lected to make measurement of complex permeability of a given film that bad on comparison and analysis of the measurement methods for permeability at home and abroad. The complex permeability was deduced by an analytical approach from the measured reflection coefficient of a shorted microstrip line with and without a ferromagnetic film material inside using the transmission line theory and Maxwell equations.
A shorted microstrip line is designed and fabricated as a prototype measurement fixture with the help of Ansoft-HFSS, and the process of the measurement is also simulated to testify correctness of the measurement method.
A measuremen t system with GPI
B bus structured is built up that consists of an 8722ES vector analyzer, personal computer, a shorted microstrip transmission-line home-made and an 82357USB/GPIB cable. Automatic application software is developed by virtual instrumentation and efficiency is improved greatly. By means of this system, a ries of FeCo-bad thin films with about 0.4micron thickness sputtered on silicon substrate are measured in 0.5-5GHz frequency range and the general correctness of the measurement results.
Microstrip reflection method can make a high speeding measurement, and the measurement technique is fast, easy to implement becau the test sample can be made and inrted easily into the test chamber. It is inferred that this method can’t only be applied to planar isotropic nano-films but also to planar anisotropic nano-films.
Keywords: Nanostructrual Magnetic Film Complex Permeability2015年2月28日
Microstrip line Microwave Measurement Network Analyzer
Virtual Instrumentation Ansoft-HFSS
1 绪论
磁性纳米薄膜微波电磁参量测量与表征是纳米膜物性测量领域的前沿性难题和热点研究课题之一5131501
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1.1 课题的意义和目的
随着现代科学技术的飞速发展光电子微机电系统显示器太阳电池等方面有着越来越多的应用
磁性薄膜更是有着举足轻重的地位
简称吸波材料在吸波材料研究中
轻质强吸收
或者对材料本身进行评估从美
俄含有Ｆｅ高损耗
是一类具有很大发展潜力的新一代隐身材料
此外
薄膜干扰抑制器
weighting同样也提出了对该类薄膜材料的微波电磁参数进行准确测量的要求
在不同的研究领域或应用场合
薄膜材料微波电磁参数常数采用复介电常数和复磁导率
来描述材料的电磁特性
复磁
导率是反映材料磁场能量存贮与损耗大小的量
()()
'''00''00r r r r r r j j εεεεεεµµµµµµ==−==−
1
0ε和0µ分别称为真空介电常
数和真空磁导率
r µ′和r
µ′′分别称为相对复磁导率的实部和虚部复磁导率谱是薄膜应用中决定其适
用性的最重要因素之一
因此
本课题的目的就是研究微波频率下磁性纳米薄膜微波磁谱的测量方法
分析测量误差来源和校准测量系统
1.2 国内外研究进展
材料的电磁参数测量最早是由Ｎｉｃｏｌｓｏｎ[6]在１９７０年提出的
按激励信号的不同
时域技术和色散傅里叶变换波谱技术三大类[5]
Æ串¸ÇƵÂÊ·¶Î§Îª
班门弄斧0.001 Hz
时域技术以
阶跃函数的脉冲波为激励信号
１６ ＧＨｚ
它的使用频率范围为60 GHz
正好落在电磁波与光波交界的区域
因此
纳米级厚度的薄膜由于其厚度太薄导致灵敏度大大降
低
实际上是含有衬底介质的测量
来困难纳米膜微波特性测量技术研究备受关注国内外研究应用在薄
膜材料复磁导率测量的频域方法主要有
双线圈法和传输/反射法重庆托福培训
1.2.1 谐振腔法
谐振腔法是将样品放入谐振腔中
它通常是将样品置于谐振
腔中电场最大磁场最小处测量样品的复介电常数
在谐振腔法中
这样就有平
行线谐振腔
矩形腔
微带腔和介质谐振腔等
外景地由于样品表面的多次反射
因此测试精度较高
和介电常数
该测试装置为矩形谐振腔
唐宗熙[8]等人采用自行研制的ＴＥ１０１５终端反射式矩形谐振腔测试单晶介我们敢 we dare
质材料的复介电常数
最大偏差仅为０．４％
华中科技大学电子科学与技术系张秀成等人采用矩形谐振腔还测量了磁性薄膜的复磁导率[9]
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гÕñÇ»Äڵĵç´Å²¨¹¤×÷
ģʽ²ÉÓÃ
introduce怎么读
TE 105模式
采取
了加大谐振腔的体积等措施
需要指出的是
要测量多频点则必须
图1.1 反射矩形谐振腔
