近年來交換耦合複合材料應用於磁記憶體中越趨廣泛，如何製作新穎的複合材料用以降低記憶體運作所需功率與雜訊為重要的議題。本研究設計之複合材料在磁性材料上增加高異向性之磁膜陣列，並利用背導式共平面波導做為鐵磁共振量測平台，針對圖形化磁性微結構進行單層與雙層樣品研究。利用具形狀異向性之磁膜的磁區分布與其下方連續膜的交互耦合作用，可於鐵磁共振頻譜中明顯觀察不同磁性材料磁區與磁膜邊界造成共振頻率的牽引，其中NiFe薄膜具有較強烈的磁矩束縛能力，不論是圖形化磁膜亦或是連續膜都具有相較於Co薄膜更為顯著的自旋共振耦合，因此本研究確立有效的鐵磁共振效應量測架構，並成功以巨觀角度下顯示本研究設計之複合材料間耦合效應。

關鍵字：交換耦合複合材料、鐵磁共振、磁性微結構、背導式共平面波導

The study of exchange coupled composite (ECC) media has become a significant aspect in magnetic recording during the past decades. It is an important issue that how to produce a novel composite material to reduce the power and noise as the memory is in operation. In this paper, the materials composed of continuous film and periodic arrays are detected magnetization precession by conductor-back coplanar waveguide (CBCPW). It is obvious that the shape anisotropy and the domains distribution on the top layer are the causes of the exchange coupling shown in the ferromagnetic resonance spectrum. Furthermore, NiFe is one kind of harder spin coupling material compared with Co not only to make into thin film but the patterns. In the research, we establish an effective measurement system of ferromagnetic resonance and successfully make a comprehensive survey on the internal coupling effect of composite material.

Key words: exchange coupled composite media、ferromagnetic resonance、magnetic micro structure、conductor-back coplanar waveguide

摘要 i
Abstract ii
致謝 iii
目錄 iv
圖目錄 vii
符號 xi
第一章 緒論 1
1.1 前言 1
1.2 研究動機與目的 2
1.3 架構規劃 3
第二章 原理與文獻回顧 4
2.1 磁性材料 4
2.1.1 磁矩 5
2.1.2 磁化動態 6
2.1.3 磁區與磁壁 7
2.1.4 鐵磁性材料 8
2.1.5 磁異向性 10
2.2 自旋波 12
2.3 鐵磁共振 12
2.4 傳輸線理論 14
2.4.1 集膚效應 15
2.4.2 阻抗匹配 16
2.4.3 散射參數 16
2.5 文獻回顧 18
第三章 研究方法 23
3.1 傳輸線設計 23
3.2 多形態磁結構鐵磁共振研究 25
3.2.1 系統架設 25
3.2.2 樣品製備 26
第四章 實驗結果與討論 28
4.1 傳輸線製作與量測結果 28
4.2 二維橢圓陣列長寬比鐵磁共振效應 29
4.3 多形態磁結構鐵磁共振量測結果 32
4.3.1 正弦波陣列多層耦合效應 32
4.3.2 二維橢圓陣列多層耦合效應 47
第五章 結論與未來展望 57
5.1 結論 57
5.2 未來展望 58
參考文獻 60

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