| 摘要 |
<p>A pressure sensor of this invention is a pressure sensor which includes a diaphragm 6 having a first surface receiving pressure, and a first thermal detection section 3 arranged to be opposed to a central section of the diaphragm through a spacer 7 and having a thermo-sensitive resistance section, and a second thermal detection section 8 arranged to be opposed to an end section of the diaphragm and having a thermo-sensitive resistance section, wherein the first thermo-sensitive resistance section and second thermo-sensitive resistance section are connected to independent, adjustable constant-current sources 23 and 28, respectively, and are connected to a differential amplifier which differentially amplifies between a voltage of the first thermal detection section, which detects a displacement quantity of the diaphragm due to pressure change as a displacement quantity of a thermal equilibrium state by the thermal detection section, and a voltage of the second thermal detection section, which does not change according to pressure. Therefore, it is possible to obtain a pressure sensor which can measure pressure with high accuracy. Since it is unnecessary to subject a surface of the diaphragm which directly receives pressure from a measurement target fluid to processing such as film formation and photo-engraving, it is possible to manufacture principal parts of a thermal pressure detector in block in large quantities on a silicon substrate at simple manufacturing steps and to obtain an inexpensive pressure sensor having the thermal pressure detector with improved accuracy and reliability. <IMAGE></p> |
