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The magnetic properties and microstructure of NiFe films deposited via ion beam deposition (IBD), pulsed, and static magnetron sputtering techniques are studied. Results show that grain size is the same among NiFe films with the same thickness regardless of the deposition technique. However, IBD films have superior (111) texture and crystallinity. It is shown that the superior magnetic properties of IBD Ta/NiFe films are due to their high crystallographic quality.

Spin valve films with synthetic antiferromagnetic CoFe/Ru/CoFe/IrMn were developed. Synthetic spin valve films were found to have large giant magnetoresistance ratio and large effective exchange field and excellent thermal stability. Spin valve readers showed high amplitude, large dynamic range and excellent magnetic stability which indicated their extendibility for ultrahigh density read head applications.

Multilayered samples of Au/NiFe were sputtered using dc magnetron sputtering, for room temperature giant magnetoresistance (GMR) studies. Two characteristic GMR peaks were observed at 15 and 28 [Angstrom] of Au spacer thickness, with values of 7.4% and 5.4%, respectively. The large magnetoresistive effect at low applied field has been attributed to the weak antiferromagnetic coupling of the magnetic layers as indicated by their calculated exchange constant values. The effect of a buffer layer on the GMR hysteresis, along with its field sensitivity were investigated for both Cr and Ta precursor layers. The Ta underlayer showed a significantly reduced GMR hysteresis. Also reported are GMR values as a function of applied magnetic field during multilayer deposition, and substrate/buffer layer effects. The multilayer structures were high quality and textured along the direction.

We have fabricated a novel giant magnetoresistive (GMR) multilayer (ML) flux sensor that is designed to operate in the current perpendicular to the plane (CPP) mode. The CPP-GMR sensor is a 0.4 [[micro]meter] diameter, 0.09 [[micro]meter] tall Co-Cu ML pedestal. The sensors are patterned using electron beam lithography. The [Al.sub.2][O.sub.3]-TiC substrate is coated with a sputter deposited [Al.sub.2][O.sub.3] film that is polished to

Large giant magnetoresistance and low saturation field for a copper thickness near 20 angstroms are exhibited by the Ni(x)Co(100-x)/Cu multilayers. The maximum sensitivity is at a point where the giant magnetoresistance has a large value. The giant magnetoresistance multilayers are related to antiferromagnetic coupling.

(Ni81Fe19Ni80Co20)/Ag granular alloy films are investigated to determine their magnetoresistance and structural properties. The films are prepared by annealing of sputtered multilayers having ultrathin magnetic layers. The magnetic resistance is 30% at a temperature of 4.2 K and the saturation field is less than 2 kilo Oersteds.

Oscillatory magnetoresistance (MR) is exhibited by Co/Cu multilayers in the form of glass/Cu/(Co(Cu)/Cu). The multilayers are manufactured by triode sputtering. The MR is 36.8% and 22.3% at temperatures of 77 and 295 K, respectively. The process of annealing on the multilayers increases MR values.

Low- and high-angle X-ray diffraction measurements are performed on Si/Re/(Co/Re) superlattices to determine the structural properties of sputtered Si/Re/(Co/Re). An optical model is developed to analyze the X-ray reflectivity data. The results show that the films are constituted by Co layers and Re rich alloys, which are 3 to 5 monolayers thick.

The influence of annealing treatments on the magnetic and structural characteristics of sputtered Co/Re superlattice structures was investigated using x-ray diffraction. The results showed that a 1 h 300 degree celsius annealing treatment induced a small increase in interfacial mixing and a contraction in lattice spacing. Further annealing treatment at 525 degrees celsius induced a significant increase in diffuse interface scattering.

Oscillatory magnetic coupling and the magnetoresistance characteristics of Co/Re superlattices were investigated. The results showed that the saturation magnetic field and the magnetoresistance magnitude of the suprlattices remained constant up to the temperature of 40 K. At higher temperatures, the superlattices saturation magnetic field and the magnetoresistance magnitude decreased linearly with the increasing temperature.

A synthesis route to mesoporous titanic with remarkable thermal stability was developed using an amine or setyltrimethylammonium-templating procedure. A method was developed to overcome the lack of thermal stability above 350 degree Celsius, by a treatment of the titanic hybrids in aqueous ammonia. It is demonstrated that parts of the amorphous titania walls of the NH3-treated titania hybrids were transferred into walls built up of rutile nanobuilding blocks before the template was thermally removed.

The first direct comparison of magnetic noise in read heads with contiguous junction (CT) and lead overlaid (LOL) design is discussed. The head signal-to-noise gain is limited by increased magnetic noise, which is expected to depend on hard bias field, and therefore free layer stiffness and head amplitude.