斜め入射成膜したRu中間層によるグラニュラ型垂直磁気記録媒体の非磁性スペーシングの低減

抄録

  We carried out oblique-incidence sputtering and analyzed in detail the growth mechanism necessary to achieve both good magnetic isolation and a reduction of the Ru interlayer thickness. The results revealed that : (1) Ru grains in the obliquely sputtered Ru thin film possessed a c -plane sheet texture due to epitaxial growth on seed layer grains, and deep gaps were observed at the grain boundaries ; (2) evaluation of the magnetic properties of the magnetic layer deposited on obliquely and conventionally sputtered Ru films suggests that magnetic isolation was enhanced by oblique-incidence sputtering ; (3) an obliquely sputtered pseudo-hcp PdW, CoCr interlayer also enhanced the magnetic isolation of the subsequent magnetic layer ; (4) following the initial growth of a continuous Ru film 1 nm thick, the grains grew, whereas by the conventional method this initial continuous Ru film grew to a thickness of 8nm, showing clear suppression of the continuous Ru layer by oblique-incidence sputtering, and (5) the media using an obliquely sputtered Ru interlayer showed V_act/V_grain = 1.9 with a top layer thickness of 8 nm ; thus, it was possible to reduce the Ru interlayer thickness by suppressing the constitution of the bottom layer.