The development and application of microthermal sensors with a mesh-membrane supporting structure

The design, fabrication, and application of microthermal sensors are presen ted in this work. The working principle of the microthermal sensor is therm istor, using platinum as the sensing material. A new mesh-membrane structur e is presented. This design can reduce the etching time and still provide s tiff-enough suspension. The fabrication of the mesh-membrane is timesaving and wastes less material because the back-side etching processes are avoide d. The fabricated thermal sensor has flat surface, a sensitivity of 3.263 d egrees C/mW, and a response time of less than 5 ms. In addition, one-wire t ype thermal flow sensors based on this kind of microthermal sensor are desi gned and fabricated. For the flow velocity higher than 1.5 m/s, the sensiti vity of the flow sensor operating in the constant-voltage mode is above 0.0 1433 mA (m/s)(-1/2), with power consumption of 14.56 mW, and is above 7.98 mV (m/s)(-1/2) in the constant-current mode with power consumption of 45.10 mW. (C) 2000 Elsevier Science S.A. All rights reserved.