摘要 |
A sensor block is disposed within a package and includes a semiconductor diaphragm and a circumferential support bonded to the inside of the package. The semiconductor diaphragm is provided with at least one diffused resistor layer formed thereon as a pressure-sensitive element, one surface of the diaphragm being subjected to a reference pressure whereas the other surface is subjected to a fluid pressure to be measured. A diaphragm breakage detecting element including an electrical conductor filament is provided zigzagging back and forth laterally across the boundary between the diaphragm and the circumferential support, the point subject to maximum stress, the conductor filament material being of substantially the same mechanical strength as the diaphragm material, so that, when the diaphragm is broken, the conductor filament is also broken, thus allowing immediate indication of the diaphragm breakage. The detecting element may include a U-shaped protrusion extending radially inwards, substantially reaching the center of the diaphragm in order to detect breakage of the diaphragm at the center thereof, where a second maximum stress occurs.
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