PAST, PRESENT AND FUTURE SMALL-BUBBLE-DIAMETER MAGNETIC MEMORY MATERIALS

To be competitive with existing and future planned mass-storage memories, cylindrical domain devices will require magnetic compositions which possess higher capabilities than those currently available. This discussion describes the more important parameters which must be known and controlled in the development of improved small-bubble diameter materials. A quick review of small-bubble-diameter compositions is presented. The body of the discussion emphasizes the status of small-bubble diameter materials. The optimum small-bubble-diameter liquid-phase epitaxial composition can be obtained only by the consideration of a number of interrelated parameters. The relationships of these variables are discussed in detail, as are the resultant effects on device performance. A look into future small-bubble-diameter garnet compositions and potential substitute bubble materials is included.