| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a flow sensor of higher sensitivity by shaping a temperature sensor line in a form conforming to a form of an isothermal line of a temperature distribution of heat from a heater wire. SOLUTION: A diaphragm membrane 12 is formed to shut the through hole 11 of the quadrangular pyramid of a semiconductor substrate 10. A heater wire 14 and temperature sensor lines 26, 28 formed on the membrane are thermally insulated from the semiconductor substrate 10. The curve temperature sensor lines 26, 28 are set symmetrically at both sides of the heater wire 14. A change of a temperature distribution of heat generated by the heater wire 14 subsequent to a movement of a fluid in a direction of an arrow 20 is detected by the temperature sensor lines 26, 28, and a resistance change of the sensor lines is detected from a voltage change. A size, a direction of a flow velocity are detected from a difference of voltages of the temperature sensor lines 26 and 28. In this case, the temperature sensor lines 26, 28 are shaped approximately equal to an isothermal of heat generated by the heater wire 14, so that a highly sensitive, highly accurate flow sensor is obtained.</p> |
