POLYMER BASED PIEZORESISTIVE SENSORS

PIEZORESISTIVE PROPERTIES OF MATERIALS FORM THE BASIS OF MANY TYPES OF SENSORS, INCLUDING STRAIN GAUGES, MICROMACHINED ACCELEROMETERS AND PRESSURE SENSORS, TACTILE SENSORS, AND FLOW SENSORS. AS GREATER DEMANDS ARE PLACED ON DEVICES FROM THE STAND-POINT OF SIZE AND COST PER CONTROLLED POINT, EASIER METHODS OF PROCESSING WHICH CAN PRODUCE SMALLER DEVICES WITH GREATER PERFORMANCE ARE REQUIRED. RESEARCHERS HAVE DEVELOPED A PROCESSABLE POLYANILINE, AS WELL AS CONDUCTIVE, ION IMPLANTED POLYMER FILMS. PRELIMINARY INVESTIGATIONS INDICATE THAT DEVICES CONSTRUCTED FROM ION IMPLANTED POLYMERS MAY HAVE PARTICULAR ADVANTAGES OVER DEVICES USING CERAMIC, METALLIC, CRYSTALLINE SILICON, AND CARBON-FILLED MATERIALS. THESE ADVANTAGES INCLUDE IMPROVED RADIATION HARDNESS, GREATER FLEXIBILITY AND RANGE OF TRAVEL, LOW MANUFACTURING COST, ABRASION RESISTANCE, AND ENVIRONMENTAL INERTNESS. THE POLYANILINE-BASED SENSORS ARE EASILY DEPOSITED ONTO THE SUBSTRATE AND CAN BE PATTERNED TO SMALL OR LARGE GEOMETRIES BY STANDARD PHOTOLITHOGRAPHIC PROCEDURES. THESE MATERIALS HAVE POTENTIAL IN THE MICROMACHINING INDUSTRY BECAUSE OF THE HIGH QUALITY OF THE FILMS THAT ARE PRODUCED ON A MICRO-SCALE (<1 MICRON), AND THEIR EASE OF PROCESSING. INVESTIGATORS ARE DETERMINING THE FEASIBILITY OF USING THE SOLUBLE POLYANILINES AND ION IMPLANTED FILMS FOR PIEZORESISTIVE DEVICES. SPECIFIC GOALS OF THIS RESEARCH ARE TO DETERMINE THE PIEZORESISTIVE GAUGE FACTOR, TO MINIMIZE TEMPERATURE EFFECTS, TO IMPROVE ENVIRONMENTAL STABILITY, AND TO CONSTRUCT PROTOTYPES OF A PRECISION LABORATORY WEIGHT SCALE AND A VACUUM/PRESSURE SENSOR BASED UPON DEVICES MADE FROM THESE MATERIALS.