Properties of SAW delay lines on GdCa4O(BO3)3 crystal at high temperatures

The surface acoustic wave (SAW) properties of delay lines with double electrode interdigital transducers on GdCa40(B03)3 crystal were measured at high temperatures. Low insertion loss changes and approximately linear dependence of the centre frequencies of the delay lines were obtained in the temperature range 20-500degC. For the XZ, YX and ZX orientations, temperature coefficients of frequency of about -80, -52, and -76 ppm/degC, respectively, were obtained. This crystal is promising for application in SAW high- temperature sensors.