Investigation of SiO2 film properties for zero temperature coefficient of frequency SAW devices

Author

Matsuda, S. ; Miura, M. ; Matsuda, T. ; Ueda, M. ; Satoh, Y. ; Hashimoto, K.

Author_Institution

Taiyo Yuden Co., Ltd., Akashi, Japan

fYear

2010

fDate

11-14 Oct. 2010

Firstpage

633

Lastpage

636

Abstract

In our paper, we discuss the temperature coefficient of frequency (TCF) in the structure of SiO₂/LiNbO₃ overlays. We studied the relationship between TCF and SiO₂ film properties measured by Fourier transform infrared spectroscopy (FT-IR) and found that changes to the atomic structure, such as the peak frequency and the Si-O-Si bond angle, correlated to those of the TCF. The TCF in the SAW device can be quantitatively predicted by the FT-IR. We were able to attain a zero TCF by changing the SiO₂ deposition conditions at a SiO₂ thickness of 0.3λ. We analyze and discuss the positive temperature characteristic of the elastic constants in the SiO₂ and the temperature coefficient of the elastic constants.

Keywords

Fourier transform spectra; bond angles; elastic constants; infrared spectra; lithium compounds; silicon compounds; sputter deposition; surface acoustic wave devices; FTIR; Fourier transform infrared spectroscopy; SAW device; SiO₂-LiNbO₃; atomic structure; bond angle; elastic constants; film deposition; silicon dioxide film properties; zero TCF; zero temperature coefficient of frequency; Films; Frequency measurement; Silicon; Substrates; Surface acoustic wave devices; Temperature; Temperature measurement; FT-IR; FWHM; SiO2; TC; bond angle; peak frequency;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium (IUS), 2010 IEEE

Conference_Location

San Diego, CA

ISSN

1948-5719

Print_ISBN

978-1-4577-0382-9

Type

conf

DOI

10.1109/ULTSYM.2010.5935494

Filename

5935494