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.

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