We have proposed a surface-micromachined new microflow sensor to resolve the problems of poor thermal isolation and low sensitivity inherently in typical thermal flow sensors. A membrane of insulating films on a vacuum cavity supports a n'-poly heatin...
We have proposed a surface-micromachined new microflow sensor to resolve the problems of poor thermal isolation and low sensitivity inherently in typical thermal flow sensors. A membrane of insulating films on a vacuum cavity supports a n'-poly heating resistor and two bidoped poly-Si thermophiles. We have investigated on heat-transfer characteristics of the sensor microstructure with the Sum-depth cavity of 100x100 μm^(2) by a two-dimensional numerical simulation as a function of the inside pressure of the cavity. As a result, the microstructure with the vacuum cavity shows better themal isolation effects than that of the air cavity.