| In this paper we present a new experimental set-up leading to characterize SAW sensor properties in high temperature up to 900°C. The characterization method consists in hanging a small piece of self-warming piezoelectric SAW device in a vacuum chamber. The device is made of the piezoelectric material to be tested equipped with its IDT plus a heating resistance, both in Platinum. The whole system is suspended from a PCB by mean of classical bonding wires. It is therefore thermally isolated from the rest of the experimental set-up. This allows using standard low-cost circuitry, to connect the SAW device to the measurement apparatus (standard coaxial feed-lines and SMA connectors). The warming being localised on the piezoelectric substrate, it also becomes possible to reach very high temperature, quickly and at low energy cost. This allows easy making of temperature cycles to test the aging of materials. In a first step, TCF values for Quartz ST and LiNbO3 Y-128° were measured in the range [20-500 °C], then compared to calculated ones in order to validate the method. In a second step, one LGS Y-X SAW Delay-Line with Pt/Ta IDT was characterized using this test method in the range [20-900 °C]. |