Fabrication of L11 Co-Pt-Cu perpendicular anisotropic films with enhanced coercivity on glass substrate

Abstract

Structure and magnetic properties of L1 1 CoPtCu thin films sputter-deposited on glass substrates were studied. Perpendicular coercivity (H c\ ) was largely enhanced by the replacement of Co with Cu with x ¼ 23 and 26, the magnetic properties obtained was better than the film grown on MgO (111) substrates. The enhancement of H c\ existed in a wide range of film thickness from 2 to 40 nm. A maximum value of H c\ of 2.7 kOe appeared in the films with thickness of 4 nm. The results of surface morphology indicated that the random distribution of the in-plane orientation of L1 1 grains induced by Pt(111) underlayer may create magnetic inhomogeneities acting as pinning site to domain walls, providing additional impedance for domain wall motion.

Sputtering perpendicular magnetic anisotropy CoPt thin film on glass substrate at room temperature

“…[6][7][8][9][10][11] Significant coercivity enhancement and ordering improvement of L1 1 CoPt films were demonstrated by adding Cu element and inserting Pt underlayer, respectively. 9-11 Later high-cost single crystal substrates such as MgO(111) and Al 2 O 3 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) were replaced by glass and consequently largely increased the applicability of L1 1 CoPt films. [12][13][14][15] From the aforementioned studies, it is concluded that the in-situ heat treatment is necessary for formation of L1 1 CoPt phase.…”

“…9-11 Later high-cost single crystal substrates such as MgO(111) and Al 2 O 3 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) were replaced by glass and consequently largely increased the applicability of L1 1 CoPt films. [12][13][14][15] From the aforementioned studies, it is concluded that the in-situ heat treatment is necessary for formation of L1 1 CoPt phase. However, this method has to spend not only the thermal annealing energy but also long time for substrate cooling to ambient temperature, which induces grain growth during film deposition.…”

“…Recently, a promising new type of material with PMA is rhombohedral CoPt film with L1 1 ordered structure, due to its lower formation temperature (200-300 C) and high magnetocrystalline anisotropy constant (K u $ 10 7 erg/cm 3 ). [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Initially, L1 1 CoPt phase film was obtained on MgO(111) substrate. 1 The effect of Pt content and deposition temperate on K u , PMA, and ordering mechanism for L1 1 structure have been investigated and the results indicate that improved magnetic properties and higher order degree can be obtained as the CoPt film is prepared at around 350 C. 4,5 To further improve magnetic properties of L1 1 phase, doping third element in CoPt film and inserting an underlayer have been carried out.…”

Modifying exchange-spring behavior of CoPt/NiFe bilayer by inserting a Pt or Ru spacer

“…However, our previous studies indicate that the presence of CoPt(222) peak can be ascribed to the fundamental peak of L1 1 -type CoPt alloy. 13,14 Comparing Fig. 1(a) with that of Fig.…”