Flexible microgripper and its application to micromeasurement of mechanical and thermal properties

Two novel micro-measurement systems using microfabricated flexible microgrippers (FMG) are presented. One system is a micro-measurement system for mechanical properties of a gripped micro-object under the microscope. In this system, the gripping force can be calculated from the elasticity of the microfinger and the driving voltage of FMG. By using this FMG-measurement system, the surface force of the cell membrane of sea urchin egg under seawater has been determined successfully from the measured deformation of the egg and the calculated gripping force of FMG. The other system is a micro-measurement system for thermal properties of micro-objects. For this system, a new microgripper with an integrated micro-thermocouple (TC-FMG) is proposed. By using micromachining, a new microfinger which has a thin film micro-thermocouple on the finger end has been developed and fabricated. The fabrication process and characterization results are discussed. By using a microfinger of TC-FMG with small heat capacity, the temperature change of a thermally actuated microfinger of standard FMG has been measured successfully. Using the measured temperature and temperature dependency of the resistivity of the microcoil, the in-air performance of the standard FMG could be written in the form of an equation which includes the resistivity change for various driving voltages.