Raman spectroscopy of carbon overcoats for magnetic disks

Abstract

The magnetic thin film media in disk drives are usually covered with hard protective overcoats. Carbon thin films are often used for this purpose but their properties can vary widely. Tough amorphous carbon films are a subject of great interest but their complete characterization requires a wide range of measurements, many of which are not easily accessible. We have found that Raman spectroscopy can serve as a convenient non-destructive technique for examining the carbon films on magnetic disks. Here we review the use of Raman spectroscopy in view of the extensive work that has been done recently on hard carbon films which have been called by a variety of names: amorphous "diamond-like carbon", "i-carbon" or "amorphous hydrogenated carbon". © 1989.