| 摘要 |
PURPOSE:To detect high pressure, by providing a thin part at the center of a sensing body, thereby imparting a function as a diaphragm, and providing the highly pressure-resisting detector, which is not broken down and from which a body to be detected does not leak. CONSTITUTION:A thin part 2a is provided at the center of a semiconductor chip 3. Strain gages 31 and 32 are provided at the center of a diaphragm constituted by the thin part, so that the stress on a silicon substrate yielded by pressure is uniformly received. Since strain gages 33 and 34 are located at both ends, which are separated from the diaphragm, the gages does not receive stress by the pressure. The four strain gages are electrically connected on the semiconductor chip. Meanwhile, when pressure (a) is applied to the sensor, the pressure is applied to the inside of the sensing body 2, the thin part is strained by the internal stress and the resistance values of the strain gages 31 and 32 are increased. Since the stress is not applied to the gages 33 and 34, the resistance values are not changed. When a constant voltage is applied across terminals 35 and 37, the value of the potential difference between terminals 36 and 38 is changed in response to the change in pressure. Therefore the pressure can be detected. |
