| 摘要 |
An electrically isolated semi-conductor transducer and method of making the same wherein a unitary piece of silicon material having opposed flat surfaces is carved out about a central portion thereof through one flat surface forming a toroidally-shaped cavity having curved bottom surfaces partway through said material surrounding a push rod having an upper flat surface lying in the same horizontal plane as the remainder of said carved out flat surface. The upper flat surface of the push rod and the curved carved surfaces surrounding the push rod are etched exposing the silicon material. A plurality of strain gages are provided on the opposite flat uncarved surface of said silicon material. These strain gages may include four diffused silicon strain gages at spaced locations along said uncarved surface. The opposite carved surface of said silicon material is then bonded to a material, such as a quartz diaphragm, electrically isolating the silicon material when the electrically isolating material is placed against a surface where pressure acting thereon is to be measured. In operation, the strain gages are electrically connected to form a Wheatstone bridge. That is, the two outer oppositely disposed gages may be in compression and the two inner gages in tension. Thus, any change in resistance of the gages produces a voltage or current output to measure the pressures acting on the undersurface of the electrically isolating material.
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