A new method for fast and accurate determination of the temperature coefficients of material constants up to 700°C. Application to LGS

Accurate sets of material constants and temperature coefficients are required to develop high temperature SAW sensors. It was previously shown that SAW Fractional Frequency Curve measurements combined with numerical optimization could help ease the burden of the experimental determination of some of these coefficients. To determine the other “missing” coefficients, it was suggested to use complementary BAW FFC measurements. However, to keep the global experimental effort as low as possible, a solution had to be found to avoid fabricating additional BAW devices on special LGS orientations. In this work, we describe a practical solution to simultaneously acquire BAW and SAW FFCs. Experimental results are presented then used to compute values of some of the missing coefficients. This demonstrates the whole method as being a promising way to determine accurate temperature coefficients with reduced experimental effort.