Effects of Ta addition in CoNi/Cr double layer film sputtered in low Ar gas pressure

The effects of tantalum and chromium up to 5 at.%, added to the CoNi magnetic layer, on the magnetic properties and media noise of a CoNi/Cr double-layer magnetic recording medium, have been investigated. The CoNi magnetic layer and Cr underlayer were deposited at argon gas pressures as low as 2 and 0.2 mTorr, respectively, using a facing-targets sputtering apparatus. Addition of Cr to CoNi layers with high remanence squareness shows slight improvement of medium noise. The addition of Ts shows significant noise reduction, to the extent of about 3 dB.<
>