Title :
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
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;
Conference_Titel :
Ultrasonics Symposium (IUS), 2010 IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4577-0382-9
DOI :
10.1109/ULTSYM.2010.5935494
