Fe

Fe50Pt50–xPdx (at. %, x = 0, 12.5, 25, 37.5, 50) alloy epitaxial films are prepared on MgO(001) substrates at temperatures ranging from room temperature to 600 °C by radio-frequency magnetron sputtering. The effects of substrate temperature and Pd/Pt composition on the order degree, c-axis distribution, and magnetic property are investigated. With increasing the substrate temperature, L10 ordering is enhanced for all the compositions. The order degree of film deposited at 600 °C decreases from 0.37 to 0.23 as the x value increases from 0 to 12.5 at. %. With further increasing the x value, the order degree increases up to 0.69. The Fe50Pt50–xPdx films with x ≥ 25 consist of only an L10(001) single-crystal with the c-axis perpendicular to the substrate surface, whereas the films with x < 25 involve two types of L10(100) variant with the c-axis lying in the film plane in addition to L10(001) variant. The c-axis distribution is influenced by the Pd/Pt composition. The magnetic anisotropy is reflecting the c-axis distribution and the order degree

Thermal stability of

Metastable L11 ordered CoPt(111) epitaxial thin films with the order degrees around 0.3 are formed on MgO(111) single-crystal substrates at 300 °C by using an ultra-high vacuum radio-frequency magnetron sputtering system. The effects of annealing after film formation on the structure and the magnetic properties are investigated. As the annealing temperature increases, the order degree gradually decreases. At 600 °C, the ordered phase disappears and the film changes to disordered structure. CoPt(111) epitaxial films with disordered structure are also prepared at room temperature and 600 °C and then these films are annealed at 300 °C. However, ordered phase formation is not recognized in the films. The metastable L11 ordered phase is preferentially formed when the film is deposited at a temperature of 300 °C. Annealing a film with disordered structure at 300 °C does not promote L11 ordering. The CoPt films involving L11 ordered structure show perpendicular magnetic anisotropies, whereas the disordered films have in-plane anisotropies. The magnetic properties are influenced by the order degree

Fe50Pt50–xPdx alloy thin films with L10 structure epitaxially grown on MgO(001) substrates

Fe50Pt50–xPdx (at. %, x = 0, 12.5, 25, 37.5, 50) alloy epitaxial films are prepared on MgO(001) substrates at temperatures ranging from room temperature to 600 °C by radio-frequency magnetron sputtering. The effects of substrate temperature and Pd/Pt composition on the order degree, c-axis distribution, and magnetic property are investigated. With increasing the substrate temperature, L10 ordering is enhanced for all the compositions. The order degree of film deposited at 600 °C decreases from 0.37 to 0.23 as the x value increases from 0 to 12.5 at. %. With further increasing the x value, the order degree increases up to 0.69. The Fe50Pt50–xPdx films with x ≥ 25 consist of only an L10(001) single-crystal with the c-axis perpendicular to the substrate surface, whereas the films with x < 25 involve two types of L10(100) variant with the c-axis lying in the film plane in addition to L10(001) variant. The c-axis distribution is influenced by the Pd/Pt composition. The magnetic anisotropy is reflecting the c-axis distribution and the order degree

Metastable Sm(Fe,Cu)

Sm-Fe thin films are prepared on Cu(111) underlayers hetero-epitaxially grown on MgO(111) single-crystal substrates by using an ultra-high vacuum molecular beam epitaxy system. The Sm/Fe composition is varied from Fe-rich (10 at. % Sm - Fe) to Sm-rich (30 at. % Sm - Fe) region including SmFe5 stoichiometry. The influence of film composition on the film structure is studied by in-situ reflection highenergy electron diffraction and X-ray diffraction. Metastable Sm(Fe,Cu)5 ordered phase formation is recognized in the Sm-Fe films with the investigated compositions. Cu atoms diffuse from the underlayer into the Sm-Fe film and substitute the Fe site in SmFe5 structure forming an alloy compound of Sm(Fe,Cu)5. The Sm-Fe films with Fe-rich compositions consist of Sm(Fe,Cu)5 and bcc-Fe phases, whereas the Sm-Fe films with Sm-rich compositions consist of Sm(Fe,Cu)5 and amorphous phases. Cu atom diffusion into Sm-Fe film is assisting the formation of ordered phase