本實驗以雙靶直流濺鍍法於玻璃基板上製作重複CoPt/Ag雙層膜多次之多層膜(CoPt/Ag)n，n為重複次數，CoPt膜總後度固定為200A，因此每層CoPt膜厚為200A/n，Ag膜厚度固定為25A及5A兩種，首先觀察重複次數n對樣品經退火處理後，產生fct序化結構之退火溫度、晶格結構及磁性質之影響。
對Ag膜厚度為25A的系列樣品而言，經退火處理後，XRD圖除顯示明顯的(111)繞射峰外，也顯示代表fct序化結構之(001)峰，產生序化之退火溫度皆低於700℃，不過，Ag膜的總厚度隨n增加而急速增加，使CoPt膜在退火處理，產生嚴重斷裂之不連續膜。
對Ag膜厚為5A的系列樣品而言，產生fct序化結構的溫度亦低於700℃，但是代表序化的(001)峰強度隨n增加而遞減，至n＞4時，完全消失，僅餘(111)繞射峰。
其次製作重複一次(n=1)的(CoPt/Ag)1膜，改變CoPt厚度為300A及100A，前者在退火溫度為700℃，經退火時間ta=20、30及40分之處理後，XRD圖均只顯示(111)峰，沒有象徵序化結構的(001)峰，但是後者在700℃，經20分鐘退火處理後，卻是出現(001)及(002)峰，其(111)峰強度遠小於(001)峰，表示(100/05)1的樣品在700℃經20分退火處理後，不僅產生fct之序化結構，及具有C軸垂直膜面之優先成長性，並且，其(001)及(002)峰之強度亦隨ta增加而增加，因此，該樣品的磁性質(M-H曲線)也同時顯示具有垂直膜面之磁異相性，即當外加磁場方向垂直於膜面時，磁滯曲線具有良好的方正性，並且頑磁場HC⊥也隨ta增加而增加。但是，軟磁性的雜相也隨ta增加而增加，不僅在磁滯曲線之低磁場處形成一階梯，頑磁場也下降，因此，最大頑磁場HC⊥=4051 Oe，是在700℃溫度下退火30分鐘得到。此外，(100/05)1之樣品經退火處理後，膜仍為不連續的。

In this study, all samples prepared on fused silica substrates using dual targets DC magnetron sputtering. In the first part of our work, a 200 A thick CoPt film was divided into multilayers by inserting Ag layer, thickness of 25 A or 5 A, into CoPt film. Our purpose is to find the effects of Ag layer induced on the film with different thicknesses of CoPt sub-layers after post-deposition annealing, such as the crystal structure ordering and the C-axis preferential growth. Our samples are expressed as (CoPt x A/Ag y A)n with x=200 A/n, y=25 A or 5 A and (n-1)=numbers of divisions.
In XRD spectrum for Ag=25 A, the peak intensities from fct (001) and (002) crystal planes increase with increasing n up to n=8 then decrease as n increase beyond n=8. However, for Ag=5 A, the largest fct (001) and (002) peak intensities are observed in the sample of n=1, which decrease as n increases .
Although peaks correspond to fct (001) and (002) crystal planes are observed in films of both Ag=25 A and Ag=5 A, their peak intensities are smaller than that of fct (111) peak. That is, the ratio of the peak intensities of I(001)/I(111) is smaller than 1. With larger I(001)/I(111) observed in the sample with n=1 and Ag=5 A. It implies that multilayered structure with Ag=25 A helps in forming fct ordered structure but not in C-axis preferential growth.
In the second part of our work, we focused at the target of increasing not only the fct ordered structure but also the preferential growth of (001) planes along the direction perpendicular to the film plane. We made different thickness of a single CoPt film with 5 A thick Ag underlayer, i.e. (CoPt x A/Ag y A)n=1 with x=300,200 and 100A. These films were subjected to different annealing temperatures Ta= 600,650, and 700℃ for a period of ta=20,30, and 40 min, respectively.
I(001)/I(111)>>1 is obtained for CoPt=100 A after annealing at Ta=700℃ for ta=20 min and I(001)/I(111) remains smaller than 1 for CoPt=300 A. I(001)/I(111) increases with increasing ta for Ta=700℃ and I(001)/I(111)>1 can also be obtained for Ta<700 ℃ when ta>20 min. As the film shows good chemical-order (large I(001)/I(002)) and preferential C-axis growth(I(001)/I(111)>>1), the more prominent perpendicular anisotropy is observed correspondingly in the relationship of magnetic field dependent magnetization, i.e. M-H hysteresis curve.
The largest coercivity of 4051 Oe is obtained with H applied perpendicular to the film of (CoPt 100A/Ag 5A)n=1 which was subjected to Ta=700℃ and ta=30 min.

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