具有近等原子比之FeRh合金呈現序化之CsCl結構且在室溫下呈現反鐵磁性，藉由加熱至約370 K時發生反鐵磁性轉為鐵磁性之一級相變且伴隨著巨大之磁熵改變、電阻之變化。由於FeRh相轉變溫度較高為了拓展FeRh的應用領域，現今大部分都是利用摻雜、介面應力等方式產生之應變來調控FeRh之相轉變溫度。
由於銅原子與鐵原子原子半徑相似，在此根據Hume-Rothery rules來判斷銅原子摻雜於FeRh合金後會置換鐵原子，使得FeRh合金在摻雜銅原子後不會因為原子大小之差異導致大幅的晶格應變且根據FeRh之平均加權價電子濃度與相轉變溫度關係來推斷FeRh在摻雜銅原子後相轉變溫度會大幅降低，因此本研究希望透過以不同的銅含量摻雜於FeRh後了解相轉變溫度與應變、價電子濃度的關係。
本研究以共濺鍍的方式製備摻雜銅之FeRh薄膜，以不同濺鍍瓦數來調控銅原子摻雜於FeRh之比例，之後藉由退火後得到序化之FeRh薄膜。透過X光繞射、能量色散X-射線光譜、X射線螢光光譜、X光吸收光譜、磁光克爾效應等技術研究其晶體結構、厚度、成分比例、磁等性質。由實驗結果發現當FeRh薄膜摻雜不同含量之銅原子後，FeRh薄膜之晶格應變隨銅摻雜濃度提高卻無太大變化且c/a比值也維持一定值但FeRh相轉變溫度卻降低，本實驗結果與現在大部分實驗所觀察到FeRh之相轉變溫度與應變有關不同，這裡發現摻雜銅後FeRh相轉變溫度變化可能與應變無關而是由價電子濃度差異所貢獻。

The near-equiatomic FeRh alloys have CsCl structure at room temperature. When heated above 370 K, exhibit first-order antiferromagnetic to ferromagnetic phase transition occurs with large change in magnetic entropy, reduction in resistivity. Due to the high phase transition temperature, in order to expand the application field of FeRh, lots of studies adjusted the transition temperature by strain induced by doping, interface stress, etc. Since the copper and iron atoms have similar atomic radius, according to Hume-Rothery rules we suppose that the copper atoms will replace the iron atoms in FeRh alloy, so that the FeRh alloy will not have a large lattice strain due to the difference in atom size by doping copper atoms and according to the relationship between the average weighted valence electron concentration of FeRh and phase transition temperature, the phase transition temperature of FeRh will be greatly reduced by doping copper atoms. In this study, FeRh films were prepared by co-sputtering, and order FeRh films were obtained after annealing. XRD, EDS, XRF and MOKE are used to study its crystal structure, thickness, composition, and magnetic properties. From the results that when the FeRh film is doped with different contents of copper, the lattice strain of the FeRh film does not change much (less than 0.03%) with the increase of the copper concentration, and the c/a ratio also maintains a certain value but the FeRh phase transition temperature decreases. The results of this experiment are different from those observed in most studies. We observed the transition temperature of Cu-FeRh may be independent of the strain and dominated by valence electron concentration.

摘要 i
Abstract ii
致謝 iii
目錄 iv
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1前言 1
1.2磁性基本理論 2
1.2.1物質磁性的分類 2
1.3 FeRh的特性 4
1.4 FeRh的應用 8
1.4.1 熱輔助磁紀錄(Heat-Assisted Magnetic Recording，HAMR) 8
1.4.2 磁阻式隨機存取記憶體（Magnetoresistive Random Access Memory，MRAM) 10
1.5文獻回顧與探討 12
1.5.1摻雜微量元素對於FeRh的影響 12
1.5.2晶格應變對於FeRh的影響 13
1.5.3退火溫度對於FeRh的影響 14
1.5.4成分對於FeRh的影響 15
1.6研究動機 17
第二章 儀器原理與實驗方法 18
2.1濺鍍(sputtering) 18
2.1.1直流濺鍍(Direct Current sputtering) 20
2.1.2射頻濺鍍(Radio Frequency sputtering) 20
2.2 同步輻射光源(synchrotron radiation light source) 21
2.3 X光繞射(X-ray diffraction) 23
2.3.1化學有序參數(chemical order parameter) 24
2.4 X光反射率(X-ray reflectivity) 25
2.4.1臨界角(critical angle) 25
2.4.2薄膜厚度(thickness) 27
2.5 X射線螢光光譜分析(X-ray fluorescence) 28
2.5.1影響螢光強度的因素 29
2.5.1.1激發率(excitation efficiency) 29
2.5.1.2螢光產率(fluorescence yield) 29
2.5.1.3基質效應(matrix effect) 30
2.6磁光科爾效應(Magneto-Optic Kerr Effect，MOKE) 31
2.7實驗步驟 34
2.7.1基板清洗 35
2.7.2樣品製備 36
第三章 結果與討論 37
3.1不同熱退火溫度對FeRh薄膜之影響 37
3.1.1 EDS成分分析 37
3.1.2 XRD、XRR分析 38
3.1.3 MOKE磁性分析 52
3.2摻雜不同含量銅原子對FeRh薄膜之影響 53
3.2.1 XRF成分分析 54
3.2.2 XRD分析 57
3.2.3 MOKE磁性分析 65
第四章 結論 71
未來展望 72
參考文獻 73

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