Effects of Air pressure and substrate bias on magnetic properties and microstructure in amorphous TbCo sputtered films

Abstract

Effects of Ar pressure and negative substrate bias voltage on magnetic properties and micro-structure in amorphous TbCo sputtered films are investigated. Magnetic properties, especially perpendicular anisotropy, depend strongly on Ar pressure and substrate bias. A perpendicular anisotropy of the order of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> erg/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> with a rectangular hysteresis loop is induced in the films deposited at 10 mTorr of Ar pressure without bias or in the films deposited with 100-150 V negative bias. In these films, the ordered fiber structure developed perpendicular to the film plane is observed, which is due to the moderate bombardment of energetic species. The large perpendicular anisotropy is associated with the ordered fiber structure.