Properties of leaky, leaky pseudo, and rayleigh surface acoustic waves on various rotated y-cut langasite crystal substrates

Michio Kadota, Jun Nakanishi, Takeshi Kitamura, Makoto Kumatoriya

Research output: Contribution to journalArticlepeer-review

37 Citations (Scopus)

Abstract

A leaky surface acoustic wave (LSAW) and a leaky pseudo SAW (LPSAW) of various rotated Y-cut langasite substrates grown by the Czochralski method were measured by an ultrasonic microscope. The measured results agreed well with the values calculated using Ilyacvc's material constants of five kinds of material. Rayleigh SAW transversal filters, having various aluminum (Al) thicknesses of interdigital transducers (IDT), were constituted on (0°, 140-150°, 24-25°) and (12°, 150-153°, 36-37°) plates. A temperature coefficient of frequency (TCF) of the Rayleigh SAW filters was measured by measuring their center frequency. It was clarified that (0°, 142°, 24.5°) and (0°, 143°, 24°) plates at normalized AI-IDT thickness (HAl/λ) 0.0125, and (12°, 153°, 37°) plates at HAl/λ = 0.0625 showed turnover temperatures of 25°C, 30°C and 28°C and excellent TCFs (ΔF/F/°C = 1.83, 1.63, and 1.95 ppm/°C). Measured results of electromechanical coupling factor on their substrates showed similar values (k52 = 0.41, 0.42 and 0.46%) to the theoretical ones. The (12°, 153°, 37°) plate having the largest coupling factor is the most suitable one for SAW devices. Furthermore, the velocity, the coupling factor, and the propagation loss of LSAW on air/various Y-X langasite plates (0°, θ, 0°) were also calculated.

Original languageEnglish
Pages (from-to)3288-3292
Number of pages5
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
Volume38
Issue number5 B
Publication statusPublished - 1999 Dec 1

Keywords

  • Coupling factor
  • LPSAW
  • LSAW
  • Langasite
  • Rayleigh SAW
  • TCF

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Properties of leaky, leaky pseudo, and rayleigh surface acoustic waves on various rotated y-cut langasite crystal substrates'. Together they form a unique fingerprint.

Cite this