LASER CRYSTALLIZATION OF SPIN-ON FERROELECTRIC THIN FILMS FOR NON-VOLATILE RANDOM ACCESS MEMORIES

PRESENT MANUFACTURING TECHNOLOGIES FOR NON-VOLATILE FERROELECTRIC RANDOM ACCESS MEMORIES (FRAM) ARE NOT SUFFICIENTLY DEVELOPED TO ENSURE REPRODUCIBLE DEPOSITION OF LARGE-AREA, HIGHLY-ORIENTED POLYCRYSTALLINE PZT (LEAD-ZIRCONATE-TITANATE) THIN FILMS ON SUBSTRATES COMPATIBLE WITH SEMICONDUCTOR INTEGRATED TECHNOLOGY. PROBLEMS OF LARGE AREA STOICHIOMETRY AND COMPATIBILITY WITH THERMALLY SENSITIVE SEMICONDUCTOR SUBSTRATES USED IN VLSIC FABRICATION ARE BEING ADDRESSED WITH LASER CRYSTALIZATION OF SPIN-ON FERROLECTRIC THIN FILMS FOR RADIATION-HARD MEMORIES. THE RESEARCH IS INNOVATIVE IN THE PRECISE CONTROL OF TEMPERATURE DISTRIBUTION AFFORDED BY LASER CRYSTALLIZATION. THE OBJECTIVES INCLUDE THE EVALUATION OF SPIN-ON DEPOSITION AND PRE-ANNEAL CONDITIONS, IDENTIFICATION OF LASER CRYSTALLIZATION PARAMETERS, CHARACTERIZATION OF PZT FERROELECTRIC THIN FILMS, AND INTEGRATION OF FILMS INTO PARALLEL PLATE CAPACITOR CONFIGURATIONS. THE SIGNIFICANCE OF LASER CRYSTALLIZATION OF SPIN-ON FERROELECTRIC THIN FILMS LAY IN MINIMIZING THE THERMAL BUDGET, INTERDIFFUSION OF SUBSTRATES/ELECTRODES/FILM, PHASE SEGREGATION, AND IN INCRASING COMPATIBILITY WITH THERMALLY SENSITIVE SEMICONDUCTOR SUBSTRATES. THE USE OF STANDARD ALUMINUM METALLIZATION TECHNOLOGY IN VLSIC MANUFACTURING IS LIMITED FOR FRAM APPLICATIONS DUE TO HIGH TEMPERATURE DIFFUSION PROBLEMS. THE PROJECT RESULTS IN THE FABRICATION OF COST-EFFECTIEV NON-VOLATILE RANDOM ACCESS MEMORIES HAVING IMPROVED QUALITY, RELIABILITY, AND PERFORMANCE.