A diamond substrate suitable for 5GHz SAW device application

Author

Fujii, Satoshi ; Jian, Chunyun

Author_Institution

Acad.-Ind. Collaboration & Intellectual Property, Chiba Univ., Chiba, Japan

fYear

2010

fDate

11-14 Oct. 2010

Firstpage

1669

Lastpage

1672

Abstract

SAW characteristics of various layer structures of SiO₂/IDT/AlN/diamond substrates that employ 2nd mode of wave (Sezawa mode) were studied both theoretically and experimentally. It was found that the SiO₂/IDT/AlN/diamond substrate would allow using thicker metal IDT in SAW device designs than other SAW substrates and also would have zero TCF characteristic at room temperature. SAW phase velocity and electromechanical coupling coefficient of the SiO₂/IDT/AlN/diamond substrate are 11150m/s and 0.5%, respectively. Fabricated 1-port SAW resonators using the diamond substrate showed Q of 660 at 5.4 GHz anti-resonance frequency. Frequency drift over temperature range of -25°C to 80°C was about 90 ppm that is even less than the ST-Quartz SAW substrate. In the end of paper, a 5 GHz band stop type SAW filter design is presented. It is shown that 30 MHz wide stopband at 6 dB rejection level can be achieved while keeping the passband insertion loss just in -0.76 dB.

Keywords

aluminium compounds; band-stop filters; diamond; microwave resonators; silicon compounds; surface acoustic wave resonator filters; surface acoustic wave resonators; SAW device; SAW resonators; Sezawa mode; SiO₂-AlN-C; antiresonance frequency; band stop type SAW filter design; diamond substrate; electromechanical coupling coefficient; frequency 30 MHz; frequency 5 GHz; frequency 5.4 GHz; frequency drift; passband insertion loss; quartz SAW substrate; rejection level; room temperature; temperature -25 degC to 80 degC; zero TCF characteristic; Diamond-like carbon; SAW filters; Substrates; Surface acoustic wave devices; Surface acoustic waves; Temperature measurement; band stop filter; diamond SAW substrate; zero TCF;

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.2010.5935505

Filename

5935505