OPTICAL METROLOGY FOR MR HEADS

The volume production of magnetoresistive heads requires fast and prec ise measurement of many critical material parameters such as film thic kness and roughness. Optical metrology is ideally suited to perform th ese measurements. We review and demonstrate the application of Ellipso metry and Scatterometry for MR head metrology. We report results for N iFe film thickness measurements and Sendust surface roughness measurem ents with sub-Angstrom precision and repeatability.