Investigation of actuation behavior for microarray thermal actuator based upon electrical analysis

Abstract

Thermal actuators based upon the principle of the thermal expansion have been utilized in various fields in the last decade. The outstanding features of a thermal actuator include simple fabrication process, large displacement, which is in proportion to temperature, and rather low operation frequency. In order to gain more insight into the actuation behavior of Micro Array Thermal Actuator, MATA, applied in MEMS, based on electrical analysis. There are two kinds of MATA, {2x4} opposite type, {1x4} parallel type compared with a single thermal actuator on the electrical analysis for each equivalent circuit, respectively. The investigation analyzed based upon basic theory and advanced computer simulation by a commercial software. The effects of operation voltage and connection length on the variations of displacement and current density of each device are studied in this work. MATA is an actuation device with a highly symmetry electrical loop through the equivalent circuit analysis. There is no current in the connection region of MATA. The phenomenon is supported by the simulation results. There is small current density, which is below 10 -9 A/μm 2 , in the connection region. Hence, the performance of MATA is strongly dominated by the geometry of a single thermal actuator, and less dependent on the type and connection number of MATA.