Developing an (Al,Ti)NxCy interlayer to improve the durability of the Ta-C coating on magnetic recording heads

Abstract

In this study, a new surface pre-treatment technique has been developed to improve the durability of the ultra-thin tetrahedral amorphous carbon (ta-C) coating for magnetic tape drive read/write heads. In this technique, prior to the deposition of an 8-nm ta-C overcoat, a 2-nm thin TiN interlayer was deposited on the heads surface and bombarded with energetic Ar and C ions. X-ray photoelectron spectroscopy results revealed that this surface pretreatment technique would lead to the formation of an atomically mixed (AlTi)NxCy interlayer which can chemically bond the interlayer to the overcoat and substrate. The effect of this atomically mixed interlayer on the wear resistance of the ta-C coating was investigated using ballon- flat tests as well as a functional tape drive tester. According to the ball-on-flat test results, the application of the (AlTi)NxCy interlayer was able to improve the wear life of the ta-C overcoat by up to 3.3 times as compared to that of the conventional ta-C coating. The results of the wear tests in a real head/tape interface were in agreement with the ball-on-flat results, and showed that while the conventional ta-C film was completely removed from the head surface, the ta-C film with (AlTi)NxCy was able to protect the head surface for wear tests of about 1.6 million meters. © Springer Science+Business Media New York 2013.