| 摘要 |
PURPOSE:To improve the temperature characteristics of a semiconductor pressure sensor, by satisfying a specific formula by regulating at least one of the factors consisting of resistance values of two resistive elements, arrangement of the two resistive elements on a silicon semiconductor diaphragm, relation between the direction along which the two resistive elements are formed and the direction of the crystallographic axis of the diaphragm, and combination of the impurity concentration of the two resistive elements. CONSTITUTION:In the specific formula: pi10sigma1beta1+mpi20sigma2beta2=0, pi10 and pi20 represent piezo coefficients of first and second resistive elements, sigma1 and sigma2 represent stresses applied to the first and second resistive elements, beta1 and beta2 represent temperature coefficients of the piezo coefficients of the first and second resistive elements and (m) represents a ratio of the resistance values of the first and second resistive elements at the temperature T0. Some regulation should be carried out for satisfying finally the formula above. The values of pi10, pi20, sigma1, sigma2, beta1 and beta2 are determined in the moment when the resistive elements are formed in a silicon semiconductor diaphragm. Accordingly, the ratio of the resistances (m) is regulated so as to satisfy the formula. For example, it is carried out by forming a plurality of resistive elements and selecting a suitable pair therefrom, or by trimming the resistive elements.
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