Fabrication and Frequency Response Characteristics of AlN-Based Solidly Mounted Resonator
XIONG Juan, GU Hao-Shuang, HU Kuan, HU Ming-Zhe
Department of Physics and Electronic Technology, Key Laboratory of Ferroelectric and Piezoelectric Materials and Devices of Hubei Province, Hubei University, Wuhan 430062
Fabrication and Frequency Response Characteristics of AlN-Based Solidly Mounted Resonator
XIONG Juan, GU Hao-Shuang, HU Kuan, HU Ming-Zhe
Department of Physics and Electronic Technology, Key Laboratory of Ferroelectric and Piezoelectric Materials and Devices of Hubei Province, Hubei University, Wuhan 430062
摘要Film bulk acoustic resonator (FBAR) with solidly mounted resonator (SMR)-type is carried out by rf magnetic sputtering. To fabricate SMR-type FBAR, alternative high and low acoustic impedance layers, Mo/Ti multilayer, are adopted as Bragg reflector deposited by dc magnetron sputtering. The influences of sputtering pressure, substrate temperature and sputtering power on the surface roughness of Bragg reflector layer are discussed. From the atom force microscopy (AFM) analysis, the surface roughness of the Bragg reflector is improved remarkably by controlling deposition conditions. Under the appropriate sputtering condition, AlN thin films with highly c-axis-preferred orientation are deposited by rf magnetron sputtering. The performance of fabricated Mo/Ti SMR shows that the electromechanical coupling coefficient is 3.89%, the series and parallel resonant frequencies appear at 2.49 and 2.53GHz, with their quality factors 134.2 and 97.6, respectively.
Abstract：Film bulk acoustic resonator (FBAR) with solidly mounted resonator (SMR)-type is carried out by rf magnetic sputtering. To fabricate SMR-type FBAR, alternative high and low acoustic impedance layers, Mo/Ti multilayer, are adopted as Bragg reflector deposited by dc magnetron sputtering. The influences of sputtering pressure, substrate temperature and sputtering power on the surface roughness of Bragg reflector layer are discussed. From the atom force microscopy (AFM) analysis, the surface roughness of the Bragg reflector is improved remarkably by controlling deposition conditions. Under the appropriate sputtering condition, AlN thin films with highly c-axis-preferred orientation are deposited by rf magnetron sputtering. The performance of fabricated Mo/Ti SMR shows that the electromechanical coupling coefficient is 3.89%, the series and parallel resonant frequencies appear at 2.49 and 2.53GHz, with their quality factors 134.2 and 97.6, respectively.
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2009, Vol. 26 
