Fabrication of electrodeposited Co–Pt nano-arrays embedded in an anodic aluminum oxide/Ti/Si substrate

Abstract: An anodic aluminum oxide (AAO) template, which is filled with the Co–Pt alloys, is a promising material for high-density magnetic recording media due to its high magnetic anisotropy and high coercivity. The porous AAO templates were fabricated by the two-step anodizing of 1-μm-thick Al thin film evaporated on top of the titanium layer with the thickness of 250nm. The AAO template with pore size of approximately 60nm and aspect ratio of 10 was obtained at voltage of 40V, temperature of 5°C, oxalic acid of 0.3M and widening time of 55min. Then the thickness of barrier is less than 20nm. The Co–Pt alloy electrodeposited at pulsed current density, pH of 4 and room temperature was successfully filled in the AAO template with pore size of 80nm and aspect ratio of 3. Then the Co–Pt alloy with Pt concentration of 45at% was uniformly filled in the template and the coercivity of 1100Oe was observed by VSM. [Copyright &y& Elsevier]