Temperatures Drift Characteristics of High Temperature Pressure Sensor Based on LTCC

Temperatures drift characteristics of wireless passive pressure sensor based on Dupont951 LTCC( LowTemperature Co-fired Ceramics) is investigated. By building high temperature test system,temperature characteristic of the sensor is tested within 0 ~ 600 ℃. Measurement results show rather large temperature drift of the sensor responses. Comparative study is carried out for a fabricated sensor with no-cavity sensing capacitor and on-chip planar spiral inductor under high temperature. The results indicate that the relative permittivity of DuPont951 LTCC material increases from 7. 8 at room temperature to 9. 04 at 600 ℃. The conclusion can be obtained that relative permittivity of LTCC material is the main factor which results in great temperature drift of the sensor.