AVS 47th International Symposium
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI-TuP

Paper MI-TuP2
Model Based Design of Next Generation Ion Beam Deposition Systems

Tuesday, October 3, 2000, 5:30 pm, Room Exhibit Hall C & D

Session: Poster Session
Presenter: H.N.G. Wadley, University of Virginia
Authors: H.N.G. Wadley, University of Virginia
W. Zou, University of Virginia
X.W. Zhou, University of Virginia
J.J. Quan, University of Virginia
Y. Sun, University of Virginia
S. Subha, University of Virginia
T. Hylton, CVC Commonwealth, Inc.
G. Hufnagel, CVC Commonwealth, Inc.
Correspondent: Click to Email
Ion beam deposition (IBD) is increasingly used for the growth of giant magnetoresistive (GMR) multilayers and magnetic tunnel junction (MTJ) devices. The performance of both device types is a very sensitive function of the layer thickness, the metal atom deposition rate, incident angle and energy, together with the reflected neutral flux and energy at the substrate. These in turn depend upon the ion gun, target, substrate geometry, the ion gun voltage, the ion type, the extent of target dither and substrate rotation, the background pressure, and any shaping of the metal flux. Optimally selecting these parameters for the three or more metal targets in the deposition system has become very challenging to IBD tool designers. A Multiscale model has been used to simulate the Ion Assisted Ion Beam Deposition of GMR structure. The model allows the thickness of a metal layer and the metal atom incident angle over the surface of a wafer to be optimized by selection of the ion type and energy, target placement, orientation and dither, substrate placement and rotation, and background pressure. A molecular dynamics approach based on embedded atom method potentials is used to investigate the effects of process parameters such as assisting ion energy on the interfacial roughness and the interlayer mixing during the deposition of giant magnetoresistive (GMR) multilayers. The atomic scale mechanisms of mixing and roughening at the various interfaces are identified. This simulation can then be used to identify improved deposition systems that can meet the film thickness uniformity, interface morphology and atomic scale structure, target needed for the high yield manufacture of GMR devices.