Langasite-Type Resonant Sensors for Harsh Environments. Issue 21 (2016)

• Record Type: Journal Article
• Authors: Suhak, Yuriy; Schulz, Michal; Wulfmeier, Hendrik; Johnson, Ward L.; Sotnikov, Andrei; Schmidt, Hagen; Ganschow, Steffen; Klimm, Detlef; Fritze, Holger
• Is Part Of: MRS advances. Volume 1:Issue 21(2016)
• Page Start: 1513
• Page End: 1518
• Publication Date: 2016
• Subjects: piezoelectric, -- sensor, -- crystal; Electrical engineering -- Congresses; Physics -- Congresses; Materials -- Research -- Congresses; Materials science -- Congresses; 620.11
• DOI: 10.1557/adv.2016.109
• Languages: English
• ISSNs: 2059-8521

Abstract

ABSTRACT: Operation of single crystalline Ca3 TaGa3 Si2 O14 (CTGS) and La3 Ga5 SiO14 (LGS) bulk acoustic wave resonators is demonstrated up to 1270 °C and 1470 °C, respectively. The mass sensitivity of such devices is about 35 cm 2 Hz/μg at 800 °C. Therefore, they are sensitive transducers suited to monitoring, for example, mass deposition processes at high temperatures. The electromechanical loss in CTGS is found to be significantly lower than that in LGS. Platinum coated CTGS samples show a remarkable long-term stability at 1000 °C in air. After an initial period of 300 h, the conductivity is found to remain nearly constant for at least 2400 h. Measurements of resonance frequency of CTGS for 1000 h show a qualitatively similar sequence, with an initial systematic increase followed by nearly constant values. In contrast, measurements on platinum-coated LGS plates show a conductivity decreasing by 15 % over a period of 5000 h.