1.8GHz AlN薄膜体声波谐振器的研制

Development of 1.8 GHz Film Bulk Acoustic Resonator Based on AlN

提出了基于AlN压电薄膜多层结构的1.8 GHz射频薄膜体声波谐振器(FBAR),并进行了研究。采用修正后的MBVD等效电路模型对器件的谐振特性进行了分析和模拟。给出了采用半导体加工工艺制备器件的工艺流程,并实际制做谐振器样品,样品的测试结果:器件的串联谐振频率fs和并联谐振频率fp分别为1.781和1.794 GHz,相应的有效机电耦合系数为1.8%;串联谐振频率处和并联谐振频率处的Q值分别为308和246。该谐振器样品实际尺寸为0.45 mm×0.21 mm×0.5 mm,可以用来制备高性能的滤波器、双工器和低相噪射频振荡器等。

The 1.8 GHz film bulk acoustic resonator （FBAR） of multi-layer structure with AlN piezoelectric film in-between was developmented. The resonant properties of the FBAR were analyzed and simulated using the modified MBVD equivalent circuit model. The fabrication processes of the FBAR samples were also given with semiconductor machining technologies. The measured Q-factors for series and parallel resonant frequencies at 1. 781 GHz and 1. 794 GHz are 308 and 246, respectively, and Keff2 is 1.8%. The size of the FBAR is 0. 45 mm ×0.21 mm ×0.5 mm. The FBAR could be expected to be used in mini-size, high performance RF filters, duplexers and low phase noise RF oscillators.