Crystal Thermometer for Temperatures up to 970°C

摘要

Gallium Orthophosphate (GaPO{sub}4) resonators with non vanishing resonant frequency-temperature response are investigated. Singly rotated BAW Y-cut resonators with a rotation angle of +27° ± 2° show nearly a linear response with a sensitivity between 43.5 ppm/°C and 46.0 ppm/°C within a temperature range from room temperature to 600°C, which is in accordance with theoretical calculations. Calculations of SAW resonators with a Y-Boule -5° cut (or Y-Boule +5° cut, which leads to the same results) predict a sensitivity between 15 ppm/°C at 25°C and 4.5 ppm/°C at 700°C.