目前所报道的流量传感器的结构基本相似,即由一个加热元件和位于其两侧的温度敏感元件组成。当气体流动时在芯片两端产生温度差,因而从两侧的温度敏感器件中得到量度流量体速度的电讯号。但是,为提高灵敏度必须增大芯片面积,带来两侧元件的失配及成品率下降。前所报导的流量传感器还需用到其它热电材料,工艺复杂性增加。我们根据MOS器件的亚阈值温度特性,利用控制芯片温度恒定所需的加热功率的变化量作为流体速度的量度,研制成功一种新型的MOS流量传感器,其灵敏度高,结构简单,芯片面积小且与MOS工艺完全兼容。 The current structure of the flow sensor is basically similar, that is, by a heating element and located on both sides of the temperature-sensitive components. As the gas flows there is a temperature difference across the chip resulting in an electrical signal from the temperature-sensitive devices on both sides that measures the body velocity of the flow. However, to increase the sensitivity, the chip area must be increased, resulting in mismatch of components on both sides and a reduction in yield. The previously reported flow sensors also require the use of other thermoelectric materials, resulting in increased process complexity. Based on the sub-threshold temperature characteristics of MOS devices, a new type of MOS flow sensor has been developed successfully using the variation of heating power required to control the chip constant temperature as a measure of the fluid velocity. The MOS sensor has a high sensitivity, a simple structure and a small chip area Fully compatible with MOS technology.