ELLIPSOMETRIC MEASUREMENT OF SOLID FLUOROCARBON FILM THICKNESS ON MAGNETIC RECORDING MEDIA

Solid fluorocarbon films were deposited on carbon overcoated magnetic recording media. The films were made by direct ion beam deposition of fluorocarbon monomers. This paper presents ellipsometric measurements on films over a range of thickness from 0.5 to 12.5 nm. Film thickness was measured using ellipsometry, and the chemical composition was stu died using x-ray photoelectron spectroscopy (XPS). A high-speed ellips ometer was set up to map thickness over the whole media surface. The e llipsometric angle Delta was found to be linearly related with the fil m thickness. Since the escape depth of the XPS is comparable to the fi lm thickness, the XPS senses the underlying carbon as well as the carb on in the film. As a result, the apparent ratio of fluorine to carbon depends on the film thickness. The ion beam deposition technique can b e used to produce films with controlled thickness and uniform composit ion. (C) 1997 American Institute of Physics.