(清華大學(xué) 材料科學(xué)與工程系 先進(jìn)材料教育部重點(diǎn)實(shí)驗(yàn)室，
北京 100084)
摘 要: 采用超高真空電子束蒸鍍方法制備了Fe/Ru多層膜， Ru層厚度固定為2 nm， Fe層厚度為0.6～5 nm， 研究了Fe層厚度的變化對(duì)薄膜結(jié)構(gòu)及其磁性能的影響。 Fe層厚度小于5 nm時(shí)， 受Ru層HCP結(jié)構(gòu)的影響， Fe層生長為六方晶格的亞穩(wěn)相。 多層膜呈現(xiàn)明顯的平面易磁化特性， 并隨Fe厚度降低而減弱。 Fe的平均原子磁矩和Fe層厚度的倒數(shù)存在線性關(guān)系， 與死層理論預(yù)言的結(jié)果相一致。 實(shí)驗(yàn)結(jié)果證實(shí)， 亞穩(wěn)相六方晶格的Fe具有鐵磁性， 其平均原子磁矩計(jì)算值為1.9μB， 略低于BCC Fe， Fe/Ru界面層的死層厚度為0.25 nm。
關(guān)鍵字: Fe/Ru多層膜； 電子束蒸鍍； 磁性； 死層； 亞穩(wěn)相
（ Key Laboratory of Advanced Materials of Ministry of Education,
Department of Materials Science and Engineering, Tsinghua University,
Beijing 100084, China）
Abstract: Fe/Ru multilayers were prepared by ultra-high vacuum electron-gun evaporation with Ru film thickness of 2 nm and Fe film thickness of 0.6-5 nm. The structure and magnetic properties of Fe/Ru multilayers were investigated. A metastable HCP Fe phase is obtained when thickness of Fe film (tFe) is less than 5 nm. Magnetic measurement indicats that the metastable HCP Fe phase exhibits ferromagnetic behavior and has a magnetic moment of 1.9μB, which is a little less than BCC Fe. A linear relationship of the magnetic moment per atom versus 1/tFe is obtained which is in correspondence with “dead layer” theory very well. The interface thickness (dint=0.25 nm) is calculated which is less than reported before. It indicats that the preparation method affects the interface thickness.
Key words: Fe/Ru multilayers; electron-gun evaporation; magnetic properties; dead layer; metastable HCP iron
