HIGH-FORCE MICROACTUATOR USING NICKEL-TITANIUM SHAPE-MEMORY ALLOY

TINI ALLOY COMPANY PROPOSES TO DEVELOP HIGH-FORCE MICRO-ACTUATORS USING VACUUM DEPOSITED SHAPE-MEMORY ALLOYS. IMPROVED MICRO-ACTUATORS ARE NEEDED FOR MICRO-MECHANICAL DEVICES NOW BEING RESEARCHED IN LABORATORIES (AND WHICH WILL REACH MARKET MATURITY IN A FEW YEARS) AND FOR AT LEAST ONE DEVICE NOW IN COMMERCIAL PRODUCTION (A GAS CHROMATOGRAPH ON A SILICON CHIP). THE POTENTIAL ADVANTAGE OF SHAPE-MEMORY ALLOY MICROACTUATORS OVER ELECTROSTATIC DEVICES IS SEVERAL ORDERS OF MAGNITUDE INCREASE IN FORCE AND DISPLACEMENT. TINI SHAPE-MEMORY ALLOYTOLERATES LARGE STRAIN, 3-5 PERCENT, AND PRODUCES LARGE STRESS, GREATER THAN 100 MPA. THIN FILMS OF TINI SHAPE-MEMORY ALLOY, WHICH HAVE BEEN DEMONSTRATED IN OUR LABORATORY TO EXHIBIT A FORCEFUL SHAPE RECOVERY, WILL BE INCORPORATED WITH SILICON COMPONENTS BY MICRO-FABRICATION. THE COMBINED TECHNOLOGIES OF SHAPE-MEMORY ALLOY AND SILICON WILL RESULT IN A NEW ENGINEERING MATERIAL FOR MICRO-MECHANICAL APPLICATIONS. THE RESEARCH OBJECTIVES TO BE ADDRESSED INCLUDE: IMPROVED VACUUM SPUTTERING TECHNIQUES TO IMPROVE YIELD AND QUALITY OF FILM; PHYSICAL CHARACTERIZATION OF TINI FILM; PLANAR FABRICATION BY MASKING AND SELECTIVE ETCHING; AND DEVELOPMENT OF FUNCTIONAL COMPONENTS SUCH AS VALVE AND PUMP ACTUATORS.