High coercivity Co-alloy thin films on polymer substrates

Abstract

Films of (10 10) textured CoCrPt have been sputtered on polymer substrates for use as thin film tape media. Underlayers of NiAl combined with various intermediate layers were employed to obtain this orientation without thermal damage to the polymer. It was found that NiAl underlayers sputtered on tape substrates have a (112) growth texture, like they do on glass. Film coercivity varied as a function of intermediate layers used, with the highest value of coercivity (3800 Oe) being obtained with a composite intermediate layer of CrMn\CoCrMn. TEM observation showed that the CoCrMn component of these intermediate layers was hexagonal with a (10 10) texture and low stacking fault density. The CoCrPt layers deposited on these CoCrMn layers had uniform grains with a lower stacking fault density, possibly due to grain-to-grain epitaxial growth of CoCrPt on CoCrMn.

NiAl Seed Layer for Obliquely Sputtered Thin-Film Tape

“…This result is in agreement with the result of NiAl films grown by dc sputtering [5]. However, this differs from the reported NiAl films deposited by radio-frequency sputtering where the (112) texture is observed 0018-9464/04$20.00 © 2004 IEEE [3], [4]. Thus, the difference in the energy of the sputtered atoms probably alters the preferential growth direction of the NiAl films.…”

Growth of oblique sputtered Co and CoCrPt thin films for high-density tape recording

“…CoCrPt and CoCrMn layers were sputtered from composite targets with the composition of Co 68 Cr 13 Pt 19 and Co 67 Cr 30 Mn 3 , respectively. At this concentration, the underlayer, CoCrMn film, is paramagnetic but still crystallizes in HCP structure providing a good lattice matching with CoCrPt layer [5]. The microstructural analyses were carried out using scanning electron microscopy (SEM) and transmission electron microscopy (TEM).…”

Obliquely sputtered Co/Cr thin film tape for bidirectional recording

“…Recently, using appropriate underlayers, an excellent CoCrPt alloy thin film with high coercivity of 300 kA/m and thin magnetic layer of 20 nm deposited on polymer substrate has been fabricated. 3 However, the film structure, which consists of NiAl underlayer and intermediate layers, is still compli-cated for application. In this article, we propose a rather simple process to obtain a thin film tape at room temperature by using oblique sputtering of Co with Cr underlayer.…”