Design of temperature-immunization system packaging for the resonant pressure sensor

Abstract

Based on the study of the material matching and structure cooperating, this paper mainly explores a new packaging structure with low thermal mismatches which can enhance the accuracy and stability of the resonant pressure sensor. According to the finite element simulation, the rule of the coefficient of thermal expansion (CTE) and the depth of the groove on the substrate, which has an influence on the temperature sensitivity, could be obtained. By analyzing the effect of temperature on the resonant frequency, it shows the temperature sensitivity of the new packaging structure is −0.97 Hz/[Formula: see text]C in 20 kPa, under the temperature range of 30[Formula: see text]C to 80[Formula: see text]C. After analyzing resonant frequency stability at different temperatures, it is found that the time for achieving stability at different temperatures of the new packaging structure is at least 10 min less than that of TO packaging structure. The average frequency’s relative variation ratio of the new packaging structure at different temperatures remains roughly the same, and the variation range is within ±[Formula: see text]0.005% as time changes. These results indicate that the new packaging structure has the characteristic of great temperature-immunization.