Microstructure of Co-evaporated CoCr films with perpendicular anisotropy

Abstract

-CO-evaporation of CO and Cr is applied to achieve good magnetic characteristics of the media deposited at low temperature, The opposed oblique incidence vapour flux induces a columnar alignment parallel to the evaporation plane. Further a process-induced segregation is present which introduces separated CO-rich and Cr-rich regions. A selective etching process is carried out to find proof of this. The large increase of M, with respect to those of a homogeneous bulk CoCr layer with the same average composition confirms this. The columns, texture axes and K axes are inclined towards the CO source, which was the main vapour flux direction. With increasing process temperature the tilting decreases. INTRODUCTIONIn deposited CoCr films relatively high substrate temperatures are necessary to achieve suitable magnetic properties.Therefore we started experiments with co-evaporation [1,2] in where two vapour beams arrive from opposite directions. Shadowing effects during deposition play a major role in the film growth. The process geometry induces separated regions of the two materials that are used; in our case CO and Cr. This so-called process-induced segregation enables us to deposit CoCr layers which have already enhanced perpendicular characteristics at low substrate temperature.

Structure of Glancing Incidence Deposited TiO2 Thin Films as Revealed by Grazing Incidence Small‐Angle X‐ray Scattering

“…This discrepancy could be attributed to the influence of the tilting angle of scatters (TiO 2 columns) on the position of GISAXS scattering maxima and/or to the tendency of the GLAD columns to form bundles separated by distances larger than the typical inter-column separation. [4,14] …”

Anisotropic In-Plane Conductivity and Dichroic Gold Plasmon Resonance in Plasma-Assisted ITO Thin Films e-Beam-Evaporated at Oblique Angles

“…As explained in the experimental section other evaporation angles were not possible because of experimental restrictions. An outstanding characteristic of the microstructure of these plasma assisted OAD thin films is that the nanocolumns are not isolated but associate in the form of bundles 14,43,47,48,58 that stretch along a direction perpendicular to the incoming flux of evaporated material. Bundling association of nanocolumns in OAD thin films is a common phenomenon previously reported for a large variety of materials.…”

“…Bundling association of nanocolumns in OAD thin films is a common phenomenon previously reported for a large variety of materials. 14,43,58 Another important characteristic of the plasma assisted OAD-ITO thin films is that the tilting angle β stays around 30 º, varying only slightly with the type of plasma gas (see Table 1). A different growing mechanism for the plasma assisted ITO OAD thin films is clearly evidenced in Figure 4 showing a cross section micrograph of a stacked bilayer of ITO films sequentially deposited in the absence (bottom) and in the presence (top) of an oxygen plasma.…”

Crossover of texture and morphology in (Ti1−xAlx)1−yYyN alloy films and the pathway of structure evolution

“…1 in [7]) only a small fraction of the vapour flux from the target section (directly below) arrives perpendicularly on the substrate, but the majority of vapour species is impinging at a certain angle with respect to the target-substrate axis. Therefore, tilted growth towards the vapour flux should be expected due to the oblique incident angles of the majority of the impinging metal species [17][18][19].…”