ION BEAM SPUTTER DEPOSITION OF GMR FILMS

G.E. McGuire, D. Temple, M. Ray, M. Lamvik, J. Lannon and D. Dausch

MCNC Research Triangle Park, North Carolina 27709, USA

Metal multilayer films exhibiting the Giant Magnetoresistive (GMR) effect are under intensive development worldwide for magnetic sensor and non-volatile random access memory applications. These multilayer films are typically deposited using magnetron or diode sputtering methods. An

alternative technique that has recently attracted attention is ion beam sputter deposition (IBSD). One of the main advantages of this technique for the growth of GMR structures is the fact that the plasma and the substrate are not in direct contact with each other, as in a typical planar magnetron configuration. Therefore, the substrate is not exposed to energetic electrons that can cause structural damage in the growing film. In addition, processing parameters, such as pressure, incident ion flux, and the energy distribution of sputtered atoms can be independently controlled; a feature not available in the more typical sputtering processes.In spite of these advantages, only a few studies have been published regarding properties of IBSD GMR structures. In addition, little information is available on effects of the controllable parameters of the deposition process on magnetization and magnetoresistive properties of the multilayer films. We have therefore undertaken a study of Fe/Cr multilayers deposited using an automated IBSD system. The films have been characterized using transmission electron microscopy (TEM), atomic force microscopy (AFM), Auger electron spectroscopy (AES), magnetization measurements and magnetoresistance measurements. Properties of the Fe/Cr multilayers deposited using either Ar or Xe ions with the primary ion beam energy varying from 100 eV to 900 eV will be presented.