Iridium Interdigital Transducers for High-Temperature Surface Acoustic Wave Applications

作者：Aubert Thierry^*; Bardong Jochen; Elmazria Omar; Bruckner Gudrun; Assouar Badreddine

来源：IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2012, 59(2): 194-197.

DOI：10.1109/TUFFC.2012.2178

• Surface acoustic wave devices
• Crystals
• Temperature sensors
• Gallium
• Temperature measurement
• Substrates

Iridium is investigated as a potential metal for interdigital transducers (IDTs) in SAW devices operating at high temperatures. SAW delay lines based on such IDTs and langasite (LGS) substrate are fabricated and electrically characterized. The results show reliable frequency responses up to 1000 degrees C. The strong increase of insertion losses beyond this temperature, leading to the vanishing of the signal between 1140 and 1200 degrees C, is attributed to surface transformation of the LGS crystal, consisting of relevant gallium and oxygen losses, as evidenced by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and secondary ion mass spectroscopy.

• 出版日期2012-2