Lupyna B. Micromechanical thermal resistive transducers

The dissertation is devoted to investigation of micrometer size bridge and membrane thermal resistive transducers manufactured by the technology of micro-electro-mechanical systems (MEMS). The thermal fields design procedures into the planar bridge and membrane resistors, based on the joint solution of the heat conductivity equation in two-dimensional approach, were offered. Mathematical models and algorithms which allow up to simulate distributions of temperature along bridge and membrane structure and into the microfluidics flow channel are designed. Intrinsic correlations between a fluid properties, transducer's thermal and electrical behavior under a basis of a self-heating effect were specified. The dependence of a heater thermal resistance on its shape and a channel geometry, the operation modes, the thickness of dielectric layers and membrane area were investigated. Ifluence of self-heating effect on the output voltage characteristics is established for non-intrusive fluid velocity transducer mounted at a flow channel wall with rectangular cross-section. The dependence of the self-balanced bridge feedback voltage from an ambient fluid temperature were defined analytically; the recommendations for choosing the self-heating technique compensation method based on switching resistors were proposed. The transducers were used into a lung diagnostics medical device.