Control of Magnetic Properties During the Processing of Single Crystal Garnet Films

Thin single-crystal rare earth iron garnet films are currently the most attractive materials for magnetic bubble domain applications. To utilize their potential, tight control of the magnetic properties is needed at each of the film processing steps. Such steps include the growth of large-area films from a supersaturated PbO-B
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O
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fluxed melt, the phosphoric acid trimming of as-grown films to adjust the bubble collapse field, ion implantation of the film surface to suppress the formation of hard bubbles and the subsequent annealing the implanted layer receives during the thermal cycling of the device fabrication steps. Control of film properties at each of these stages will be discussed and data presented to show how each of these stages may be optimized.