PURPOSE:To improve linearity and temp. characteristic, by providing a thin- walled strain inducing part in a part of a measuring diaphragm consisting of single crystal silicon, and forming an oxidized film on the surface of the diaphragm so as to cover only the gate resistance formed in the strain inducing part. CONSTITUTION:A measuring diaphragm 10 consisting of (n) type single crystal silicon has a central rigid body 12, and a fixing part 14, and forms a thin-walled strain inducing part 16. The body 12 is formed in smaller wall thickness than the part 14, and a clearance is formed between the same and a fixing base 18 consisting of borosilicate glass. Plural pieces of (p) type gage resistors 20 are formed in the part 16. Two resistors 20 are formed in the position near the part 14 and the two resistors near the body 12. The resistors are combined in a bridge and an output is drawn out differentially thereform. An oxidized film 22 of silicon dioxide is formed on the top surface of the diaphragm 10 so as to cover only the resistors 20 after the resistors 20 are formed. The output from the resistors 20 is drawn out with electrodes 24 formed on the top surface of the film 22. The sensor having excellent linearity and temp. characteristic is thus made.
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