Development of High Performace Acoustic Wave Devices Using Single Crystalline Diamond

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360131
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Electron device/Electronic equipment
• Research Institution: Chiba University
• Principal Investigator: HASHIMOTO Ken-ya 千葉大学, 工学(系)研究科(研究院), 教授 (90134353)
• Co-Investigator(Kenkyū-buntansha): SATOSHI Fujii 千葉大学, 事務局, 特任研究員 (30598933) ; TATSUYA Omori 千葉大学, 大学院工学研究科, 助教 (60302527)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 弾性表面波 / 単結晶ダイヤモンド / AlN / Sc-AlN / 共振子

Outline of Final Research Achievements

This project was aimed at developing surface acoustic wave (SAW) devices with excellent performances using single-crystalline diamond (SCD).
First, a high quality AlN film was deposited on the SCD, and a high performance SAW resonator with the Q factor of 5,700 at 5 GHz was realized. We showed that the surface roughness of SCD critically influence the achievable Q factor. Next, highly piezoelectric Sc-AlN films were also deposited on the SCD, and it was demonstrated that wideband and low loss SAW filters are realizable in the 3 GHz range, which is hard when conventional piezoelectric materials are applied.
We also revealed that on the piezoelectric film/non-piezoelectric substrate substrate structure, the effective electromechanical coupling can be enhanced by the mass-loading of electrodes.

Free Research Field

超音波工学