| 摘要 |
<p>PURPOSE: To provide a high speed response-type flow sensor with low power consumption by forming a radiation preventive film on either one of the upper and lower faces or both faces of a heater wire formed on a silicon substrate having a hollow part for thermal insulation while having a protective film between them. CONSTITUTION: A heater wire 3 is formed on the upper face of a silicon substrate 1 in the condition the silicon substrate is coated with an under protective film 2a and an upper protective film 2b of SiO2 , etc. In parallel to that, an upper radiation preventive film 4a and an upper radiation preventive film 4b are formed on both upper and under face sides while having the protective films 2a, 2b, respectively, between the films and the face sides. A hollow part 7 opened downward for thermal insulation is formed in a part of the substrate corresponding to the heater wire 3. Consequently, the heat radiated from the heater wire 3 can be lessened by the preventive films 4a, 4b and a flow sensor with little thermal loss and low power consumption can be obtained.</p> |
