FePd合金材料在磁性儲存元件上是具有潛力的候選材料之一，本實驗以真空直流磁控濺鍍的方式沉積Fe/Pd多層膜到室溫的MgO[001]基板上，並且以同步輻射X光量測來驗證多層膜成長方式可以讓FePd-FCT晶粒的a、b軸方向沿著膜面而讓c軸垂直於膜面，實驗將濺鍍完成的Fe/Pd多層膜以700℃在真空環境退火2-10小時，利用感應偶合電漿質譜儀、能量分佈X光光譜、X光反射率、X光繞射、X光吸收對樣品的元素組成和結構進行分析以及討論。
實驗發現濺鍍完成的未退火樣品其結構是具有非晶形多孔性多層膜的結構，而隨著退火時間的增加，膜厚以及多孔性的下降表示膜密度的上升，表示Fe/Pd多層膜逐漸轉為單層的FePd合金，X光繞射圖譜在退火樣品只有發現FePd-FCT結構中沿著c軸方向的[001]和[002]繞射峰且從Rocking-curve可以看到具有優選取向，代表FePd-FCT的晶粒容易長成c軸垂直於膜面，而從X光吸收光譜模擬以及擬合結果可以得知退火後的樣品Fe原子局部結構符合FePd-FCT結構，表示其他如Fe-BCC、Pd-FCC或者FeO的含量極少。

We aimed to study the local structure change as amorphous FePd multilayer transformed into the ordered face-center-tetragonal FePd under annealing. [Fe (2 nm)/Pd (2 nm)]30 multilayer on MgO [001] substrate were prepared using a home-built magnetron sputtering system. As made samples were annealed at 2, and 10 hours at 700 ℃ in high vacuum condition. From the EXAFS analyses for the nearest scattering paths of Fe-Fe and Fe-Pd, we found that despite the inversive change in the lattice parameters c and a, the c/a ratio and cell volume of the FePd became smaller which demonstrates a more compact structure of FePd as an effect of longer annealing time.

目錄
中文摘要 i
英文摘要 ii
致謝 iii
目錄 iv
表目錄 vi
圖目錄 vii
第一章 序論 1
1.1 前言 1
1.2 磁性儲存原理 1
1.3 研究動機 3
第二章 實驗儀器與分析方法 4
2.1真空直流磁控濺鍍系統 4
2.2感應耦合電漿質譜分析儀 (Inductively coupled plasma mass spectrometry, ICP-MS) 5
2.3 能量散佈X光光譜儀(Energy Dispersive X-ray Spectrometer, EDX) 6
2.4 同步輻射光源 (Synchrotron Radiation) 7
2.5 X光繞射 (X-ray diffraction) 8
2.6 X光吸收光譜(X-ray absorption spectroscopy) 17
2.7 X光反射率(X-ray Reflectivity) 21
第三章 樣品製備與量測 24
3.1 多層膜濺鍍 (Multilayer sputtering) 24
3.2 感應偶合電漿質譜儀量測 25
3.3 X光繞射實驗量測 25
3.4 X光反射實驗量測 26
3.5 X光吸收光譜量測 26
3.6 能量分佈X光光譜儀量測 26
第四章 實驗結果與討論 27
4.1 成分組成分析 27
4.3 X光繞射圖 31
4.4 X光吸收光譜分析 34
第五章 總結與未來展望 42
參考文獻 43
附錄 46

表目錄

表1.2.1 具有高磁異向能的材料 2
表2.5.3.1 個別基本晶胞的消光度關係 14
表3.3.1 各別元素、合金以及氧化物在入射光能量8 keV時的繞射峰位置 25
表4.1.1 樣品元素比例表 28
表4.1.2 ICP-MS與EDX實驗比較表 28
表4.1.3 同一樣品在不同局部共三次EDX實驗 28
表4.2.1 XRR擬合參數表 30
表4.3.1 XRD繞射圖數據表 33
表4.4.2.1 樣品的Pd L3-edge X光吸收圖譜數據表 36
表4.4.3.1 EXAFS擬合數據表 41

圖目錄

圖1.2.2 (a)無序FCC(b)序化FCT結構 3
圖2.1.1.1 濺鍍示意圖，左邊黑色圈為氬離子，右邊橘色為靶材物質 4
圖2.1.1.2 濺鍍設備示意圖 5
圖2.2.1.1 感應偶合電漿質譜儀示意圖 6
圖2.3.1 入射光使內層電子激發放出特徵X光螢光示意圖 6
圖2.3.2 不同物質放射出相對應能量的特徵X光 7
圖2.4.1 同步輻射光能量範圍以及波長 8
圖2.4.2 台灣的國家同步輻射研究中心光源系統 8
圖2.5.3.1 等效照射體積示意圖 10
圖2.5.3.2 不同元素的散射因子 12
圖2.5.3.3 溫度因子隨角度增加而減少 13
圖2.5.3.4 鐵原子的散射因子 15
圖2.5.4.1 狹縫大小對於繞射峰強度以及解析度關係 16
圖2.6.4.1 X光吸收光譜可區分為主要的XANES和EXAFS兩段 18
圖2.6.4.2 目標原子經吸收X光後放出的光電子與鄰近原子相互作用[27] 19
圖2.6.5.1 X光吸收邊緣與軌域的關係圖 20
圖2.6.5.2 L-edge與分子軌域關係圖 21
圖2.7.4.1 X光與全反射角關係 24
圖4.2.1 X光反射率對退火時間變化圖 29
圖4.2.2 樣品密度、膜厚、表面粗糙度以及多孔性對樣品退火時間變化圖 30
圖4.3.1 樣品隨退火時間變化的X光繞射圖 32
圖4.3.2 (a)樣品隨退火時間變化的X光繞射圖，(b)、(c)為退火10、2小時樣品的FePd-FCT [002]繞射峰的Rocking-curve 33
圖4.4.2.1 樣品的Pd L3-edge X光吸收圖譜 36
圖4.4.2.2文獻的Pd L3-edge X光吸收圖譜 37
圖4.4.3.1 FePd-FCT結構中Fe周圍原子環境模擬圖 38
圖4.4.3.2 FEFF模擬實空間中Fe在FePd合金的散射路徑 39
圖4.4.3.3 未退火樣品的EXAFS擬合結果 40
圖4.4.3.4 退火2小時樣品的EXAFS擬合結果 40
圖4.4.3.5 退火10小時樣品的EXAFS擬合結果 41
圖4.4.4.1 Fe L3-edge X光吸收光譜 42

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