電漿表面處理於具垂直異向性磁性薄膜之研究與應用

Investigation and application of surface plasma treatment on magnetic films with perpendicular anisotropy

10.6843/NTHU.2010.00308

李建緯

表面粗糙度 ； 磁性穿隧接面 ； 垂直異向性 ； 層間交互偶合 ； 磁性圖案化

清華大學材料科學工程學系學位論文

2010年

碩士

賴志煌

英文

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本論文研究主題可分為兩部份。在第一部份中，深入探討鐵鉑薄膜表面粗糙度，及對應Neel coupling的改變。在鍍製完下層垂直磁性穿隧接面（magnetic tunnel junction） 結構至鐵鉑層後，對其表面進行電漿表面處理，之後鍍上氧化鎂層及上層鐵磁層。鐵鉑層的表面粗糙度在過程中獲得改善，然而不同處理條件所對應的Neel coupling變化不大。另一方面，利用氬氣和氧氣混和組成的電漿進行表面處理，我們發現即使以極短時間進行表面處理，上下鐵磁層仍會去耦合（decoupling），另外利用光電子能譜儀 （X-ray photoelectron spectroscopy）及穿透式電子顯微鏡可以證實表面氧化物的存在。在第二部份中，我們成功利用電漿轟擊進行磁性圖案化（magnetic patterning）。這個部份先將試片利用光學顯影方法定義為分隔的小區域，之後再以電漿轟擊定義磁區。由於小區域內磁區被限制，其翻轉行為因而改變。這個利用電漿進行磁性圖案化的製程未來有機會應用於圖騰媒介（patterned media）的開發。