Fabrication and Magnetic Properties of Patterned Thin Films
Garrett, Claude H.
Magnetic materials and their Magneto-Optical properties play a key role in today's technology. Research in this field can uncover new methods of recording digital data, or developing new types of force sensors. The magnetic properties of thin films were examined using the Magneto-Optical Kerr Effect and a Vibrating Sample Magnetometer (VSM). Other properties were observed using spreading resistance measurements and null ellipsometry. Patterns on the thin films, stress, film thickness and orientation were observed to change the magnetic properties. The magnetic coercivity (He) was used to gauge the changing magnetic properties of the thin films. Thin NiFe-35% and NiFe-45% films were magnetron sputtered onto cleaned silicon and glass substrates. A laser beam writing system and photolithography techniques were used to etch large arrays of microstructures. The gross magnetic properties are then examined using a vibrating sample magnetometer. Detailed magnetic properties of the patterned films were examined using a Magneto-Optical Kerr Tracer. The Kerr rotation of the specular and first diffracted peak was measured as a function of the applied field. These results as well as the results of the influence of patterning on the magneto-elastic properties of the thin films are examined. We can isolate the parameters of photolithography to demonstrate a stable process, and determine the smallest achievable pattern size with a laser beam writing system. Furthermore, we have also examined how the magnetic properties of thin films change with various patterns, and examined the effects of the intrinsic stress of the thin film on its magnetic properties.
thin films, magnetic properties, fabrication
Garrett, C. H. (2002). Fabrication and magnetic properties of patterned thin films (Unpublished thesis). Southwest Texas State University, San Marcos, Texas.