Influence of Copper on А1 to L1₀ Phase Transformation in Nanoscale Fe₅₀Pt₅₀ Films

• Дата: 2015
• Автори: Makogon, Yu.M., Pavlova, O.P., Sidorenko, S.I., Verbytska, T.I., Verbytska, M.Yu., Fihurna, O.V.
• Формат: Стаття
• Мова: English
• Опубліковано: Інститут металофізики ім. Г.В. Курдюмова НАН України 2015
• Назва видання: Металлофизика и новейшие технологии
• Теми: Металлические поверхности и плёнки
• Онлайн доступ: http://dspace.nbuv.gov.ua/handle/123456789/111883
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Цитувати: Influence of Copper on А1 to L1₀ Phase Transformation in Nanoscale Fe₅₀Pt₅₀ Films / Yu. M. Makogon, O. P. Pavlova, S. I. Sidorenko, T. I. Verbytska, M. Yu. Verbytska, O. V. Fihurna // Металлофизика и новейшие технологии. — 2015. — Т. 37, № 4. — С. 487-498. — Бібліогр.: 18 назв. — англ.

By the methods of materials science, the effect of intermediate Cu layer with low surface energy (≅1.83 J/m²) (top, intermediate, and underlayer) in [Fe₅₀Pt₅₀(15 nm)/intermediate Cu(7.5 nm) layer/Fe₅₀Pt₅₀ (15 nm)]n (where n=1,2), top Cu(7.5 nm) layer/Fe₅₀Pt₅₀(15 nm) and Fe₅₀Pt₅₀ (15 nm)/underlayer Cu(7.5 nm) film compositions on SiO₂(100 nm)/Si(001) substrates on diffusion phase-formation processes and L1₀ phase formation, its structure, and magnetic properties at annealing in vacuum is studied. The film compositions are prepared by magnetron sputtering on thermally oxidized SiO₂ layer by thickness of 100 nm on monocrystalline Si(001) substrate. Subsequent heat treatment is carried out at high vacuum of 1.3∙10⁻³ Pa in the 300—900°C temperature range during 30 s at each temperature. As determined, the chemically disordered A1(FePt) phase is formed in all as-deposited films. The formation of chemically ordered L1₀(FePt) phase in [Fe₅₀Pt₅₀(15 nm)/Сu(7.5 nm) intermediate layer/Fe₅₀Pt₅₀(15 nm)]n films (where n=1,2) with intermediate layers takes place during annealing at 700°C and is accompanied by sharp coercivity increase, which also rises after subsequent high-temperature annealing. In the films with top copper layer, the temperature of L1₀(FePt) phase formation rises up to 900°C. In the films with copper underlayer, the formation of L1₀(FePt) phase is not detected by X-ray analysis, but small coercivity increasing after annealing within the temperature range of 800—900°C can testify that ordering processes proceed.