Institute of Microelectronics, NCSR-Demokritos, P.O. Box 60228, 15310, Aghia Paraskevi, Athens, Greece.
Sensors (Basel). 2010;10(10):8981-9001. doi: 10.3390/s101008981. Epub 2010 Oct 8.
This paper presents the evaluation of a miniature liquid microflow sensor, directly integrated on a PCB. The sensor operation is based on the convective heat transfer principle. The heating and sensing elements are thin Pt resistors which are in direct electrical contact with the external copper tracks of the printed circuit board. Due to the low thermal conductivity of the substrate material, a high degree of thermal isolation is obtained which improves the operating characteristics of the device. The sensor is able to operate under both the hot-wire and the calorimetric principle. In order to fully exploit the temperature distribution in the flowing liquid, multiple sensing elements are positioned in various distances from the heater. A special housing was developed which allowed implementation of the sensor into tubes of various cross sectional areas. The sensor sensitivity and measurement range as a function of the sensing element distance were quantified. A minimum resolution of 3 μL/min and a measurement flow range up to 500 μL/min were achieved.
本文介绍了一种微型液体微流量传感器的评估，该传感器直接集成在印刷电路板 (PCB) 上。传感器的工作原理基于对流热传递原理。加热和感应元件是薄的 Pt 电阻器，它们与印刷电路板的外部铜迹线直接电接触。由于衬底材料的导热率低，因此可以获得高度的热隔离，从而改善了器件的工作特性。传感器能够在热线和量热法原理下工作。为了充分利用流动液体中的温度分布，多个感应元件被放置在距加热器不同的距离处。开发了一种特殊的外壳，允许将传感器安装在各种横截面积的管中。量化了作为感应元件距离函数的传感器灵敏度和测量范围。实现了最小分辨率为 3 μL/min 和测量流量范围高达 500 μL/min。
