Iridium interdigital transducers for high-temperature surface acoustic wave applications

Author

Aubert, T. ; Bardong, J. ; Elmazria, O. ; Bruckner, G. ; Assouar, B.

Author_Institution

Carinthian Tech Res., St. Magdalen, Austria

Volume

59

Issue

2

fYear

2012

fDate

2/1/2012 12:00:00 AM

Firstpage

194

Lastpage

197

Abstract

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°C. The strong increase of insertion losses beyond this temperature, leading to the vanishing of the signal between 1140 and 1200°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.

Keywords

X-ray chemical analysis; high-temperature electronics; interdigital transducers; iridium; scanning electron microscopy; secondary ion mass spectra; secondary ion mass spectroscopy; surface acoustic wave delay lines; surface acoustic wave transducers; surface acoustic waves; Ir; SAW delay lines; SAW devices; electrical characterisation; energy-dispersive X-ray spectroscopy; high-temperature surface acoustic wave applications; insertion losses; iridium interdigital transducers; langasite substrate; oxygen losses; scanning electron microscopy; secondary ion mass spectroscopy; surface transformation; temperature 1140 degC to 1200 degC; Crystals; Gallium; Substrates; Surface acoustic wave devices; Temperature measurement; Temperature sensors;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/TUFFC.2012.2178

Filename

6156820