AVS 45th International Symposium
    Thin Films Division Tuesday Sessions
       Session TF-TuM

Paper TF-TuM6
Atomistic Scale Modeling of Ion Assisted Deposition of GMR Multilayers

Tuesday, November 3, 1998, 10:00 am, Room 310

Session: Thin Films for Sensing and Data Storage
Presenter: X.W. Zhou, University of Virginia
Authors: X.W. Zhou, University of Virginia
H.N.G. Wadley, University of Virginia
Correspondent: Click to Email
Giant magnetoresistance (GMR) is found in many ferromagnetic metal multilayers separated by thin copper films. Low interfacial roughness and intermixing are critical for obtaining the high giant magnetoresistance ratio needed for magnetic random access memories. A three dimensional molecular dynamics physical vapor deposition model has been developed and used to explore the effects of Ar- and Xe- ion assisted deposition of model Ni/Cu/Ni multilayers. The results indicate that the interfaces can be significantly flattened by ion assisted deposition provided the ratio of ion to metal atoms exceeds about 2.0. However, we found that as the assisting ion energy is increased, interfacial roughness decreases, but intermixing of the layers increases. A modulated ion energy / flux strategy for ion assisted deposition has then been investigated in which the ion beam energy / current was reduced while depositing the first few monolayers of each new metal layer. This strategy was found to successfully reduce both interfacial roughness and intermixing. The optimal ion to metal atom ratio and ion incident energy were identified.