Demands of highly piezoelectric materials for radio frequency acoustic wave devices

✍ Scribed by Hashimoto, Ken-ya

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 751 KB
• Volume: 208
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.201000589

✦ Synopsis

Abstract

This paper is aimed at making it clear why we device engineers are keen to have high quality and highly piezoelectric materials for sophisticated radio frequency (RF) surface and bulk acoustic wave (SAW/BAW) devices to be used in future communication systems. First, RF SAW/BAW resonators and their filter application are introduced, and it is shown how the resonator properties directly reflect to achievable filter performances. Discussions are also provided on how the acoustic and piezoelectric properties of base materials influence the total device performances. An emphasis is given to the fact that use of high quality and highly piezoelectric materials is essential for the applications. It is also demonstrated how high performance devices are achievable by the use of high coupling materials such as a single‐crystalline LiNbO~3~ substrate with specific crystallographic orientation with extremely large electromechanical coupling. Further discussions are given on new applications of extremely wideband SAW/BAW resonators employing ferroelectric materials with extremely large electromechanical coupling.