LASER DEPOSITION OF MODULATED-STRUCTURE FERROELECTRIC THIN FILMS FOR NON-VOLATILE MEMORIES

FERROELECTRIC THIN FILM DEVICES OFFER A NUMBER OF ADVANTAGES FOR USE AS COMPUTER MEMORIES, INCLUDING HIGH BIT-DENSITY, NONVOLATILE LOWVOLTAGE OPERATION OVER A WIDE TEMPERATURE RANGE, SHORT ACCESS AND CYCLE TIMES, AND RELATIVELY HIGH RADIATION HARDNESS. TO RESPOND TO THE NEED OF DESIGNIING AND DEVELOPING LIGHTWEIGHT, RADIATION HARD, HIGH PERFORMANCE ELECTRONIC CIRCUITS FOR USE IN INTERCEPTORS, ACTIVE AND PASSIVE SENSORS, AND DATA/SIGNAL PROCESSING DEVICES USED IN ANTISATELLITE APPLICATION, AMERICAN RESEARCH CORPORATION OF VIRGINIA SUGGESTS THE FABRICATION OF THIN FILM MODULATED STRUCTURES OF PT AND PZT FERROELECTRIC MATERIAL USING LOW TEMPERATURE LASER ABLATION TECHNIQUES. THE TARGET OF OPPORTUNITY IN THIS PROPOSAL IS THE DEVELOPMENT OF LOW-TEMPERATURE, LASER DEPOSITION PROCESSES FOR THE PREPARATION OF MODULATED STRUCTURE FERROELECTRIC THIN FILMS WHICH WILL REQUIRE LOW SWITCHING FIELDS WHILE YIELDING A LARGE SIGNAL CHARGE. PROGRAM RESEARCH OBJECTIVES INCLUDE DESIGN OF A LOW-PRESSURE REACTOR, EVALUATION OF TARGET/SUBSTRATE GEOMETRY AND LASER EVAPORATION PARAMETERS, FABRICATION AND ANALYSIS OF FERROELECTRIC MATERIAL, AND FABRICATION AND ANALYSIS OF MODULATED STRUCTURE FERROELECTRIC THIN FILMS. THE TECHNIQUE OF LASER EVAPORATION OF FERROELECTRIC THIN FILMS OFFERS EXCELLECT CONTROL OVER CHEMICAL COMPOSITION AND RESULTING MICROSTRUCTURES AND IS EXPECTED TO BE EASILY ADAPTABLE TO DEVICE MANUFACTURING. THE INNOVATION IN THE PROPOSED TECHNOLOGY IS IN THE USE OF LASER-ASSISTED EVAPORATION TO PRODUCE HETERO-EPITAXIAL FILMS OF MULTILAYER PZT-PT COMPOSITION LEADING TO FASTER SWITCHING TIMES AND IMPROVED SIGNAL STRENGTH FOR FERROELECTRIC COMPUTER MEMORIES. SUCCESSFUL COMPLETION OF THE PROGRAM OBJECTIVES, WILL PROVIDE A MAJOR ADVANCE IN FERROELECTRIC THIN FILM QUALITY FOR DEVICE PRODUCTION.