<title>Combined ellipsometer, reflectometer, scatterometer, and Kerr effect microscope for thin film disk characterization</title>

Abstract

A new instrument has recently been developed for characterizing various properties of thin film magnetic disks. Since defects on thin film disks can take many forms, it is useful to combine many different optical detection techniques into a single tool. This greatly improves the chances of detecting a wide variety of defects, both topographic and non- topographic. The ellipsometer part of the instrument is used to measure the lubricant, carbon layers and organic contamination on thin film disks. The reflectometer is used to detect scratches, pits, particles, and texture angle. The scatterometer is used to detect particles, corrosion, and surface roughness. The Kerr effect microscope detects magnetic patterns on thin film disks and can be used as a replacement for ferrofluid marking of magnetic defects. The instrument also incorporates a built-in precision diamond scribe for marking defects. The theory of operation and the design of this instrument will be discussed. Examples will be given of the different types of defects and thin films that can be detected on thin film disks.